rotex installation and maintenance instructions

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ROTEX GCU compactInstallation and maintenance instructionsGas Combi Unit compact

TypesGCU compact 315GCU compact 324GCU compact 515GCU compact 524GCU compact 533

GCU compact 315 BivGCU compact 324 BivGCU compact 515 BivGCU compact 524 BivGCU compact 533 Biv

GBEdition

0085 CO 0180

List of contents

2 ROTEX GCU compact -

1 Guarantee . . . . . . . . . . . . . 41.1 Warranty conditions . . . . . . . . . . . . . . . . . . . . . . 4

2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.1 Observing instructions . . . . . . . . . . . . . . . . . . . . 52.2 Warning signs and explanation of symbols . . . . 52.3 Avoid danger . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.4 Proper use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52.5 Instructions for operating safety . . . . . . . . . . . . . 6

2.5.1 Before working on the heating system . . . . . . . . . .62.5.2 Electrical installation . . . . . . . . . . . . . . . . . . . . . . . .62.5.3 Installation room . . . . . . . . . . . . . . . . . . . . . . . . . . .62.5.4 Requirements for the heating water . . . . . . . . . . . .62.5.5 Heating system and sanitary connection . . . . . . . .62.5.6 Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62.5.7 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62.5.8 Instructing the user/owner. . . . . . . . . . . . . . . . . . . .6

3 Product description. . . . . . . . . . . . . . . . . . . 73.1 Design and components . . . . . . . . . . . . . . . . . . 7

3.1.1 GCU compact 315 / 324 . . . . . . . . . . . . . . . . . . . . .73.1.2 GCU compact 515 / 524 / 533. . . . . . . . . . . . . . . . .8

3.2 Brief description . . . . . . . . . . . . . . . . . . . . . . . . . 9

4 Set-up and installation . . . . . . . . . . . . . . . 114.1 Dimensions and connection dimensions . . . . . 11

4.1.1 Connection dimensions for the heating and hot water connections . . . . . . . . . . . . . . . . . . . . . .12

4.2 Installation versions . . . . . . . . . . . . . . . . . . . . . 144.2.1 Operation independent of ambient air. . . . . . . . . .154.2.2 Operation partially independent of ambient air . . .164.2.3 Ambient air dependent operation . . . . . . . . . . . . .16

4.3 Transport and delivery . . . . . . . . . . . . . . . . . . . 164.4 Installing the Gas Combi Unit compact . . . . . . 16

4.4.1 Selecting the installation site . . . . . . . . . . . . . . . .164.4.2 Setting up the unit . . . . . . . . . . . . . . . . . . . . . . . . .174.4.3 Remove the sound insulation hood. . . . . . . . . . . .18

4.5 Air/flue system (LAS) . . . . . . . . . . . . . . . . . . . . 184.5.1 General instructions for flue system . . . . . . . . . . .184.5.2 Connecting a flue gas line. . . . . . . . . . . . . . . . . . .194.5.3 Flue gas system kits . . . . . . . . . . . . . . . . . . . . . . .20

4.6 Water connection . . . . . . . . . . . . . . . . . . . . . . . 214.6.1 Connecting the safety group (SBG) . . . . . . . . . . .214.6.2 Connecting hydraulic lines . . . . . . . . . . . . . . . . . .224.6.3 Connect the condensate drain . . . . . . . . . . . . . . .23

4.7 Connection Control and Electrics. . . . . . . . . . . 234.7.1 Instructions concerning electrical connection . . . .234.7.2 Establishing the electrical connection . . . . . . . . . .234.7.3 Integrated heating circulation pump and

3-way-valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .254.8 Temperature sensor. . . . . . . . . . . . . . . . . . . . . 25

4.8.1 Connecting the exterior temperature sensor RoCon OT1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25

4.9 Connect the gas line, check the burner setting for gas type. . . . . . . . . . . . . . . . . . . . . . 26

4.9.1 Important instructions for gas connection . . . . . . .264.9.2 Connecting the gas line. . . . . . . . . . . . . . . . . . . . .264.9.3 Installing/removing the burner trim . . . . . . . . . . . .264.9.4 Checking the gas pre-installation . . . . . . . . . . . . .27

4.10 Optional connections . . . . . . . . . . . . . . . . . . . . 284.10.1 Mixer module RoCon M1 . . . . . . . . . . . . . . . . . . .284.10.2 Room control RoCon U1 . . . . . . . . . . . . . . . . . . . .28

4.10.3 Internet Gateway RoCon G1. . . . . . . . . . . . . . . . 284.11 Filling the system . . . . . . . . . . . . . . . . . . . . . . 28

4.11.1 Check the water quality and adjust the pressure gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4.11.2 Filling the hot water heat exchanger . . . . . . . . . . 284.11.3 Filling the storage tank . . . . . . . . . . . . . . . . . . . . 284.11.4 Filling the heating system and the storage tank

charging circuit . . . . . . . . . . . . . . . . . . . . . . . . . . 30

5 Start-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . .315.1 Initial start-up. . . . . . . . . . . . . . . . . . . . . . . . . . 31

5.1.1 Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 315.1.2 Checks before start-up . . . . . . . . . . . . . . . . . . . . 315.1.3 Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315.1.4 After start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

5.2 Checklists for start-up . . . . . . . . . . . . . . . . . . . 33

6 Control unit . . . . . . . . . . . . . . . . . . . . . . . . .346.1 Operating elements on the boiler control

panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346.2 Replacing the operating section RoCon B1 . . 356.3 Changing the sensors . . . . . . . . . . . . . . . . . . . 35

6.3.1 Changing the flow temperature sensor / return temperature sensor and pressure sensor . . . . . . 36

6.3.2 Changing the internal mixer sensor for heating support (only GCU compact 5xx) . . . . . . . . . . . . 36

6.3.3 Changing the storage tank temperature sensor . 37

7 Gas burner . . . . . . . . . . . . . . . . . . . . . . . . . .387.1 Structure and brief description . . . . . . . . . . . . 387.2 Safety function . . . . . . . . . . . . . . . . . . . . . . . . 397.3 Burner setting . . . . . . . . . . . . . . . . . . . . . . . . . 39

7.3.1 Setting values . . . . . . . . . . . . . . . . . . . . . . . . . . . 407.3.2 Establishing access to the burner . . . . . . . . . . . . 407.3.3 Checking and setting the burner . . . . . . . . . . . . . 407.3.4 Starting problems - calibrate the firing unit,

starting output burner blower and setting the gas volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

7.3.5 Setting ignition and Ionisation electrodes . . . . . . 437.4 Dismantling the burner . . . . . . . . . . . . . . . . . . 43

8 Hydraulic connection . . . . . . . . . . . . . . . . .458.1 Hydraulic system connection . . . . . . . . . . . . . 45

9 Service and maintenance . . . . . . . . . . . . . .479.1 General overview of service and maintenance 479.2 Service and maintenance tasks . . . . . . . . . . . 47

9.2.1 Checking the connections and pipes. . . . . . . . . . 479.2.2 Checking and cleaning the condensate drain. . . 479.2.3 Checking and cleaning the burner. . . . . . . . . . . . 48

10 Faults and malfunctions . . . . . . . . . . . . . . .4910.1 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . 4910.2 Overview of possible malfunctions . . . . . . . . . 4910.3 Fault codes . . . . . . . . . . . . . . . . . . . . . . . . . . . 5110.4 Rectifying burner faults and STB faults. . . . . . 5310.5 Emergency operation . . . . . . . . . . . . . . . . . . . 54

10.5.1 Parallel operation . . . . . . . . . . . . . . . . . . . . . . . . 54

11 Taking out of service. . . . . . . . . . . . . . . . . .5511.1 Temporary shutdown . . . . . . . . . . . . . . . . . . . 5511.2 Final shutdown and disposal. . . . . . . . . . . . . . 55

List of contents

ROTEX GCU compact - 3

12 Technical data . . . . . . . . . . . . . . . . . . . . . . . 5612.1 Basic data . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56

12.1.1 GCU compact 3xx . . . . . . . . . . . . . . . . . . . . . . . . 5612.1.2 GCU compact 5xx . . . . . . . . . . . . . . . . . . . . . . . . 5712.1.3 Integrated gas burner . . . . . . . . . . . . . . . . . . . . . 5812.1.4 Integrated heating circulation pump, 3-way valve 58

12.2 Gas type, connection pressures . . . . . . . . . . . .5912.3 Tightening torque . . . . . . . . . . . . . . . . . . . . . . .6012.4 Flow rate and residual feed height . . . . . . . . . .6012.5 Temperature sensor . . . . . . . . . . . . . . . . . . . . .6012.6 Electrical connection diagram. . . . . . . . . . . . . .61

13 Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

14 List of keywords . . . . . . . . . . . . . . . . . . . . . 63

15 For the chimney sweep . . . . . . . . . . . . . . . 6415.1 Data for designing the flue gas pipe . . . . . . . . .6415.2 Emissions measurement. . . . . . . . . . . . . . . . . .64

1 x Guarantee


1 Guarantee

1.1 Warranty conditionsThe legal guarantee conditions fundamentally apply. Our war-ranty conditions beyond that can be found online on your sales representative's webpage.

2 x Safety


2 Safety

2.1 Observing instructionsThis instruction is the >> Original Version << in your language.

Please read this manual carefully and thoroughly before pro-ceeding with the installation or modification of the heating system.

These instructions are intended for authorised and trained heating and sanitation experts who have experience in the proper installation and maintenance of heating systems and hot water storage tanks by virtue of their technical training and knowledge.

This manual provides all the necessary information for instal-lation, start-up and maintenance, as well as basic information on operation and settings. Please go through the attached docu-ments for a detailed description of operation and control.

All heating parameters needed for smooth operation are already factory-set. Please refer to other relevant documents for infor-mation on setting the control.

Relevant documents– ROTEX GCU compact:

– For the operator– Operating manual for the operator.

– ROTEX RoCon BF: Operating instructions.– When connecting additional ROTEX components; the associ-

ated installation and operating instructions.

The guides are included in the scope of supply for the individual units.

2.2 Warning signs and explanation of symbolsMeaning of the warningsWarnings in this manual are classified according into their se-verity and probability of occurrence.

Special warning signsSome types of danger are represented by special symbols:

ValiditySome information in this manual has limited validity. The validity is highlighted by a symbol.

Order numberInformation about order numbers are identified with the shopping basket icon .

Handling instructionsInstructions on actions are shown as a list. Actions of whichthe sequential order must be maintained are numbered.

Results of actions are identified with an arrow.

2.3 Avoid dangerROTEX Gas Combi Unit compact conforms to the state-of-the-art and meets all recognised technical requirements. However, improper use may result in serious physical injuries or death, as well as property damage. Install and operate only ROTEX Gas Combi Unit compact to avoid danger:– as stipulated and in perfect condition,– with an awareness of the safety and hazards involved.

This assumes knowledge and use of the contents of this manual, the relevant accident prevention regulations and the recognised safety-related and occupational medical rules.

2.4 Proper useThe ROTEX GCU compact may only be used for the heating of hot water heating systems. It may only be erected, connected and operated only according to the indications in this manual.

The ROTEX GCU compact must only be operated with the inte-grated circulation pump and only in connection with a control system that has been approved by ROTEX.

Any other use outside the intended use is considered as improper and leads to a loss of warranty. The operator alone shall bear re-sponsibility for any resulting damage.

Proper use also includes observing the relevant maintenance and servicing conditions. Spare parts must at least satisfy the technical requirements defined by the manufacturer. This is the case, for example, with original spare parts.

DANGER!

Draws attention to imminent danger.

Disregarding this warning can lead to serious injury or death.

WARNING!

Indicates a potentially dangerous situation.

Disregarding this warning can result in serious injury or death.

CAUTION!

Indicates a situation which may cause possible damage.

Disregarding this warning can lead to damage to property and the environment.

This symbol identifies user tips and particularly useful information, but not warnings or hazards.

Electric power

Danger of explosion

Risk of burning or scalding

Risk of poisoning

Pay attention to the stipulated tightening torque (See chapter 12.3 "Tightening torque")Only applies for units with unpressurised solar system connection (Drain Back).Only applies for units with a bivalent solar system con-nection (BIV).


2 x Safety2.5 Instructions for operating safety

2.5.1 Before working on the heating systemWork on the heating system (such as installation, connectionand initial start-up) may only be carried out by authorised,trained heating technicians.Switch off the main switch and secure it against unintendedswitching on when carrying out any work on the heatingsystem.Seals must not be damaged or removed.Make sure that the safety valves comply with the require-ments of EN 12828 when connecting on the heating side, and with the requirements of EN 12897 when connecting on thedomestic water side.

2.5.2 Electrical installationElectrical installations must only be conducted by electricalengineers and in compliance with valid electrical guidelinesas well as the specifications of the energy supply company.Before completing the mains connection, compare the mainsvoltage, indicated on the type plate (230 V, 50 Hz) with thesupply voltage.Before beginning work on live parts, disconnect them from thepower supply (switch off main switch, remove fuse) andsecure against unintentional restart.Equipment covers and service panels must be replaced assoon as the work is completed.

2.5.3 Installation roomOperate ROTEX GCU compact only if sufficient combustionair supply is ensured. If you operate the ROTEX GCUcompact in a room-air independent manner with a concentricair/flue gas system (LAS) dimensioned as per ROTEXstandard, this is fulfilled automatically and there are no otherconditions for the equipment erection room. With installationin residential rooms, this method of operation applies exclu-sively.Make sure that, with installation in a room-air dependent orlimited room-air independent manner, an inlet air opening tothe outside of at least 150 cm2 is provided.Do not operate the ROTEX GCU compact by the ambient airdependent method in rooms with aggressive vapours (e.g.hair spray, perchloroethylene, carbon tetrachloride), strongdust formation (e.g. workshop) or high humidity (e.g. laundry). Strictly keep the minimum distances to walls and otherobjects (see chapter 4.1).

2.5.4 Requirements for the heating waterAvoid damage caused by deposits and corrosion: Observe the relevant regulations of technology to prevent creation of cor-rosion products and deposits.

Measures for desalination, softening or hardness stabilization are necessary, if the filling and top-up water have a high total hardness (>3 mmol/l - sum of the calcium and magnesium con-centrations, calculated as calcium carbonate.

Using filling water and top-up water which does not meet the stated quality requirements can cause a considerably reduced service life of the equipment. The responsibility for this is entirely that of the operator.

2.5.5 Heating system and sanitary connectionCreate a heating system according to the safety requirements of EN 12828.With sanitary connection, you must observe;– EN 1717 - Protection of potable water from contamination

in domestic water installations and general requirementsconcerning safety equipment for the prevention of domes-tic water contamination by back-flow

– EN 806 - Technical regulations for domestic water instal-lations (TRWI)

– and, in addition, the country-specific legal regulations.

During operation of the ROTEX GCU compact with hot water storage, the storage tank temperature may exceed 60°C, partic-ularly when solar power is used.

Therefore, incorporate scald protection during the installation of the system (domestic hot water mixing construcion, e.g. VTA32, 15 60 16).

2.5.6 FuelThe ROTEX GCU compact is factory set to the gas type indicated on the burner sticker and on the settings type plate and adjusted to the gas pressure indicated on the burner sticker.

Operate the unit only with the gas type and gas pressureindicated on these stickers.Installation and adaptation of the gas system must only beconducted by personnel qualified for this work and incompliance with valid gas installation related guidelines aswell as the applicable regulations of the gas supply company.

2.5.7 OperationOperate ROTEX GCU compact only with closed silencerhoods.Only operate the ROTEX GCU compact if all the require-ments as per the checklist in chapter 5.2 are fulfilled.

2.5.8 Instructing the user/ownerBefore you hand over the heating system, explain to theowner how he/she can operate and check the heatingsystem.Hand over the technical documentation (at least the operatinginstruction manual and operating handbook) to the user andadvise him that these documents must be made available atall times and be stored in the immediate vicinity of the unit.Make a record of the handover by filling out and signing theinstallation and instruction forms jointly with the user/owner.

3 x Product description


3 Product description

3.1 Design and components

3.1.1 GCU compact 315 / 324

Fig. 3-1 Structure and components GCU compact 315/324 - plan view (for legend designations, see tab. 3-1)

Fig. 3-2 Structure and components GCU compact 315 / 324 - front view (for legend designations, see tab. 3-1)

Fig. 3-3 Structure and components GCU compact 315 / 324 - Schematic view (for legend designations, see tab. 3-1)


3 x Product description3.1.2 GCU compact 515 / 524 / 533

Fig. 3-4 Structure and components GCU compact 515 / 524 / 533 - plan view (for legend designations, see tab. 3-1)

Fig. 3-5 Structure and components GCU compact 515 / 524 / 533 - front view (for legend designations, see tab. 3-1)

Fig. 3-6 Structure and components GCU compact 515 / 524 / 533 - Schematic view (for legend designations, see tab. 3-1)

3 x Product description


Tab. 3-1 Legend from fig. 3-1 to fig. 3-6

3.2 Brief descriptionDie ROTEX Gas Combi Unit compact (GCU compact) is a fully preassembled gas condenser unit., which is built into a water storage tank. The excellent heat insulation properties of the plastic storage tank ensure that heat losses are kept to a minimum. The aluminium boiler body is inserted in a metal housing in the cover of the storage tank. The complete flue gas unit is surrounded by fresh air.

Operating modeThe ROTEX GCU compact is designed such that it can be operated independently of the ambient air (concentric flue gas/air inlet piping). The burner suctions the combustion air directly in through an installation shaft or a double-walled flue gas pipe. This procedure is recommended by ROTEX and has many advan-tages:– The heating room does not need any ventilation opening into

the open air and therefore does not cool down.– Lower energy consumption.– Additional energy recovery in the flue gas pipe through pre-

heating the combustion air.– Contamination from the environment of the burner are not

suctioned in. The heating room can thus be used as awork-space, laundry room etc. at the same time.

– Possible to set up in loft areas or attic.

The condensate which arises is collected in the flue gas collector and transported into the storage tank via a plastic pipe where it is neutralised.

The pressureless storage water serves as heat storage medium. Useful heat is supplied and led out by completely submerged, helically intertwined stainless steel corrugated tubes (1.4404).

The hot water zone in the storage tank works as a combination of heat storage and geyser (see fig. 3-3 and fig. 3-6).

The cold water which flows out when the hot water is removed is first routed to the storage tank at the very bottom of the heat ex-changer, where it cools the lower area of the storage tank down as much as possible. The readiness zone is heated by a heat ex-changer for charging storage tank (SL-WT) which is heated using the gas burner, heated from top to bottom where the water also flows.

On its way to the top, the domestic water continuously absorbsthe heat of the storage tank water. The flow direction, operating on the principle of counter-flow, and the coil-shaped heat ex-changer create a pronounced temperature layering in the hot water storage tank. As high temperatures can be maintained for a very long time in the upper section of the storage tank, a high hot water output is achieved even if water is drawn off over a long period of time.

– On the GCU compact 515/515-BIV, 524/524-BIV models, theSL-WT ends approx. 40 cm above the floor of the container.Only the hot water zone about it is heated by the boiler. Thetank volume below it is heated only on using the solar energy.

– On the GCU compact 315/315-BIV, 324/324-BIV, 533/533-BIV models, the SL-WT is pulled down all the way to the con-tainer floor. The entire storage volume is heated by the boiler(greater hot water output readiness).

Optimum water hygieneLow flow or unheated zones on the domestic water side are com-pletely excluded with the ROTEX GCU compact. It is impossible for sludge, rust or other sediments to be deposited, as can be the case with other large volume tanks. The water which is fed into the system first is also discharged first (first in, first out principle).

1 Cold water connection (1" AG) 2)

2 Hot water (1" AG) 2)

3 Storage charge - flow (1" AG) 4 Storage charge - return flow (1" AG) 5 Heater- flow (1" AG)* 2)

6 Heater- return flow (1" AG)* 7 Solar - flow (1" IG) 8 Draining connection or solar return

flow9 Exhaust10 Supply air11 Sensor immersion sleeve for storage

temperature sensor tDHW12 Upper filling connection and condensate

overflow connection 13 Condensation drain pipe 14 Condensate pipe15 Heating heat exchanger (boiler body)16 Heat exchanger (stainless steel) for drink-

ing water heating17 Heat exchanger (stainless steel) for stor-

age tank charging or heating support18 Heat exchanger (stainless steel) for biva-

lent storage charge 1)

19 BIV storage charge - flow 1)2) (1" AG)

20 BIV storage charge - return flow 1)

(1" AG)21 Solar inflow layering pipe22 Heating circulation pump23 Burner blower

24 Safety overpressure valve (heating circuit) 3)

25 Connection for SBG GCU compact 3)

26 Gas connection (G ½" IG) with connected gas hose

27 Boiler control panel with RoCon BF control28 Heat insulation29 Burner trim30 Silencer hood31 Insertion mount, sound insulation hood32 Type plate33 Setting type plate34 Threaded insert for carrying loop35 Cover screen boiler control panel

3UV DHW3-way change valve (distribution valve

)

3-way change valve (mixer valve)

tDHW Storage temperature sensor tR Return temperature sensor 1 in FLS1

(boiler circuit) tR Return temperature sensor 2 (boiler

circuit) tV1 Flow temperature sensor (boiler circuit)

tV2 Internal mixer sensor (boiler circuit)

A Gas boilerB Storage tank (polypropylene double walled

jacket with PUR hard foam heat insulation)C Unpressurised storage tank waterD Hot water zoneDS Pressure sensorE Solar zoneFLS1

Flow sensor with return temperature sen-sor tR1 (boiler

circuit) Optional: ROTEX Solaris R3 regulation and pump unit

AG Male threadIG Female threadÜM Union nut

Safety devicesObserve tightening torque!

* Ball cock (1" IG) is supplied with the equip-ment

1) Only valid for types with BIV configuration2) Recommended accessories:

Non-return valves (2 pcs.), 16 50 703) Recommended accessories:

Safety group SBG GCU compact,15 70 46

3UV


3 x Product descriptionLow scalingOn the storage tank side only one deposition of scale is possible. All the stainless steel heat exchanger pipes in the storage tank water largely remain without fixed coverings. This means that no scale can build up which would continuously reduce the effi-ciency of heat transfer in the course of operation.

The thermal and pressure expansion and high flow rates in the domestic water heat exchanger release any possible scale de-posits, which are then flushed away.

Solar utilisationThe hot water storage tank of ROTEX GCU compact can also be used by solar energy. Depending on the available heat from the sun, the entire hot water storage tank can be heated up. The stored heat is used for hot water generation and also for heating support on types GCU compact 5xx. The ISM ("Intelligent Storage Manager") controls the integrated 3-way valves in such a way that the solar heat yield is optimally divided up and used for the hot water generation and heating support. The high total storage capacity allows for bridging of the periods without any solar yield.

If a ROTEX pressurised solar system or an external heatingboiler is used as an external heat generator, this means that only one of the - listed in section 3.1 - GCU compact with BIV config-uration is permitted as the primary hot water storage unit.

On the models GCU compact BIV, the complete storage tank is designed as a hot water zone. It is possible to make thermal use of solar energy for hot water preparation. In connection with a ROTEX Solaris plant connected in series (preheating stage), the solar proportion is optimised.

Safety managementThe entire safety management of the ROTEX GCU compact is entrusted to electronic control. This effects a safety switch-off in the event of water shortage, gas shortage or undefined operating states. A corresponding fault signal provides an engineer with all the necessary information for troubleshooting.

Electronic controlAn electronic digital controller combined with the "intelligent" au-tomatic firing unit of the burner controls all heating and hot water functions automatically for the direct heating circuit and a storage tank charging circuit.

Optionally, connected mixer modules RoCon M1 ( 15 70 68)can be used to connect and regulate one or more mixed circuits.

All settings, displays and functions are made via the integrated RoCon BF control. The display and operating elements offer con-venient operating possibilities.

As an option, for increased convenience, a digital room controller (RoCon U1, 15 70 34) is available as an option. This can be used as a remote control and a room thermostat.

Using the optional gateway (RoCon G1, 15 70 56), the con-troller can be connected to the internet. This means that the ROTEX GCU compact can be controlled remotely via mobile phone (using an App).

Condensing technologyThe calorific value engineering makes optimum use of the energy contained in the heating gas. The flue gas is cooled down in the boiler and in the flue system - when operated independently of ambient air - such that the temperature is below the dew point. A part of the water vapour generated on combustion of the gas thus condenses. The condensation heat is fed to the heating, unlike low temperature boilers, which makes efficiencies of over 100 % possible (in relation to the lower heating value).

4 x Set-up and installation


4 Set-up and installationIncorrect set-up and installation would render the manufacturer's guarantee for the unit void. If you have questions, please contact our Technical Customer Service.

4.1 Dimensions and connection dimensions

WARNING!

Incorrectly erected and installed gas devices may not operate properly and are dangerous for the health and safety of individuals.

The ROTEX GCU compact must be installed onlyby heating engineers authorised and trained bygas or energy supply companies.

A Side viewB Front view

C Top view

Fig. 4-1 Installation dimensions for flue gas pipe at the rear (for values see tab. 4-1)

A Side viewB Front view

C Top view

Fig. 4-2 Installation dimensions for flue gas pipe at the side (for values see tab. 4-1)

A B

C

A B

C

C



Tab. 4-1 Connection- and set-up dimensions GCU compact in mm (in relation to fig. 4-1, fig. 4-2, fig. 4-10, fig. 4-13, fig. 4-14)

4.1.1 Connection dimensions for the heating and hot water connections

GCU compact 3xx

Dim. GCU compact 3xx GCU compact 5xxh1 1380h2 1920 1950h3 1560hR 2070 2100r1 110 250r2 380 540s1 345s2 350, 4701) 200, 3201)

s3 535, 3651), 2852) 500, 3301), 2502)

s4 370, 2001), 210, 401),

s5 750, 6301), 5002)

s6 750, 6301), 5002) 750, 6301)

sD 150t 615 790w 595 790

1) When installing the test adapter to the rear.2) When using a shorter exhaust pipe D8 L25 ( 15 50 79.0102) instead of

the exhaust pipe D8 L50 contained in SET.

Dim. GCU compact 3xx GCU compact 5xx

Fig. 4-3 Connection dimensions GCU compact 3xx (view from behind)

A Front sideB Rear side

Gc GCU compact

Fig. 4-4 Connection dimensions GCU compact 3xx (plan view)

A

B

Gc 3xx



GCU compact 5xx

Fig. 4-5 Connection dimensions GCU compact 5xx (view from behind)

A Front sideB Rear side

Gc GCU compact

Fig. 4-6 Connection dimensions GCU compact 5xx (plan view)

ROTEX recommends the installation of gravity brakes ( 16 50 70) or syphoning (lead the connection lines straight downward) of the potable water connections to avoid an increased loss through cooling.

Gc 5xx

A

B


4 x Set-up and installation4.2 Installation versions

The ROTEX GCU compact are designed basically for operation independent of the ambient air. They are fitted with a con-centric flue gas /air supply pipe DN 60/100.

The SET GCU1 ( 15 50 79.17) kit can be used to flexibly ar-range the flue gas /air supply pipe for the connection directions to the rear or upwards and extended to DN 80/125.

1-6 Different set-ups (For a description, see section 4.2.1 to 4.2.3)

CA Inlet air (combustion air)FG Flue gasRV Rear ventilation

a Set up variant for room-air independent operation (flue gas/inlet air concentric)

b Set up variant for limited room-air inde-pendent operation (flue gas/air inlet sepa-rate)

c Set up variant for room-air dependent op-eration

d Longitudinally ventilated shaft with fire re-sistance duration of 90 min (in residential buildings with low headroom 30 min). Observe country-specific regulations for fire-resistance periods!

e Ventilation opening (1x150 cm² or2x75 cm²)

f Rear ventilation opening (150 cm²)

Fig. 4-7 Installation variants for the GCU compact

In some cases, the resonance in the flue system can amplify the noise at the mouth of the flue gas pipe. The noise level can be effectively reduced with the applica-tion of a silencer (E8 MSD, 15 45 78 or E11 MSD,

15 45 79).

Using the ROTEX GCU compact in room-air inde-pendent operation with a concentric flue gas/air supply pipe is recommended by ROTEX. If possible, choose this set-up!

In the event of limited room-air independent (separate flue gas/air supply pipes with a single-walled con-necting pipe) and in the event of room-air dependent operation, the installation room must have a ventilation opening of at least 150 cm2 into the outdoors.

This reduces the overall energy efficiency of the building in the framework of the European Guideline 2010/31/EU: EPBD.



4.2.1 Operation independent of ambient air

Set-up version 1The ROTEX GCU compact with the SET GCU1 and the concentric LAS connection line SET H or SET K is connected to the chimney or an installation shaft.– The combustible air supply from the outside runs through the

chimney or through an installation shaft.– The flue gas discharge using a flue gas pipe to the outside

runs through the same shaft as the air supply.– Minimum vertical distance between flue gas exit and roof

ridge: 40 cm.

Set-up version 2The ROTEX GCU compact is placed directly below the roof. Connection with SET GCU1 und SET L.– The combustible air supply and flue gas discharge run

through a concentric dual pipe.– The combustible air supply from the outside runs through the

outer ring-shaped gap of the dual tube and the flue gas dis-charge to the outside runs through the inner tube.

– Minimum vertical distance between flue gas exit and roof sur-face: 40 cm.

– Minimum height of the flue gas pipe: 2 m.

Set-up version 3The ROTEX GCU compact is not placed directly below the roof. The dual tube for the combustible air supply and flue gas pipe runs through the roof truss.– The combustible air supply and the flue gas discharge run

through a concentric dual pipe (as in Installation version 2).– In the area of the roof truss, the dual pipe for the combustible

air supply and the flue gas duct must be laid through a protec-tive pipe with sufficient fire resistance or be structurally sepa-rated from the roof truss.

Set-up version 4The ROTEX GCU compact with the SET GCU1 and the LAS connection line SET H or SET K is connected to the exterior wall system SET G.– The combustible air supply from the outside runs through the

ring-shaped gap in the dual pipe, through the outer wall (suc-tion from below).

– The flue gas discharge to the outside runs through a concen-tric pipe, through the outer wall and then up to at least 40 cmover the roof surface. In the external area, the outer air gapserves as heat insulation for the flue gas pipe.

Set-up version 5If, for constructional or legal/regulatory reasons, the shaft used for the flue gas routing is not suited for sending the combustion air through it at the same time, the combustion air must be sent through a separate line.

If the flue gas connection line to the shaft is double-walled and is surrounded by the combustion air, there are no additional venti-lation requirements on the installation room.

– Combustion air inlet is routed from the outside via the ade-quately sealed inlet air which is connected directly to the con-centric exterior pipe of the connection line. The air inlet lineshould be sized so that the suction resistance at nominalpower is less than 50 Pa.

– The connection line between the ROTEX GCU compact andthe installation shaft is completely concentric and surrounded by combustion air.

With equipment erection in residential rooms, only one of the set up variants 1 to 4 is permissible.

If the wall feed through has a height of less than one meter above the plot, ROTEX recommends sending the combustible air through a separate air supply pipe (mounting height: about 2 m). W8 ZR, 15 50 79.00 66 or W11 ZR, 15 50 77.00 30


4 x Set-up and installation4.2.2 Operation partially independent of ambient air

Alternative to set-up variant 5The ROTEX GCU compact is operated with separately routed inlet air/ flue gas lines (2 line system).– Combustion air inlet is routed from the outside via the ade-

quately sealed inlet air through the external wall. The air inletline should be sized so that the suction resistance at nomi-nal power is less than 50 Pa.

– Flue gas dissipation to the outdoors is via the chimney or aninstallation shaft. If the connection line between the ROTEXGCU compact and the installation shaft is single-walled or isnot completely surrounded by combustion air, a ventilationopening of at least 150 cm2 is required.Appropriate measures must be taken to ensure that theburner cannot be operated if the ventilation opening is closed.

– The installation shaft where the flue gas line runs must be rearventilated. In the lower area there must be a rear ventilationopening of at least 150 cm2 must be provided.The cross-section of the installation shaft must be sized sothat between the external wall of the flue gas line and theinternal face of the installation shaft the following mini-mum distance must be maintained:– with a rectangular shaft cross-section: 2 cm– with round shaft cross-section: 3 cm.The rear ventilation opening must not be in rooms where a positive pressure is generated (e.g. by controlled apartment ventilation, a tumble-drier etc.).

4.2.3 Ambient air dependent operation

Set-up version 6The ROTEX GCU compact can be connected even with venti-lation and air-conditioning. Thereby, only the inner flue gas pipe (plastic pipe Ø 60 mm) of the concentric air-flue gas pipe is con-nected to the flue gas line. The device sucks the combustible air from the installation room through the ring-shaped gap of the jacket pipe.

For the flue gas routing to the outdoors, the shaft sizing and the rear ventilation, the same conditions apply as in section 4.2.2. A ventilation opening to the outside of 150 cm2 is imperative.

4.3 Transport and delivery

The ROTEX GCU compact is delivered on a pallet. All industrial trucks, such as lifting trucks and forklift trucks, are suitable for transporting it.

Scope of delivery– ROTEX GCU compact (preassembled),– Bag of accessories (see fig. 4-8),– Outside temperature sensor (RoCon OT1), for weather-con-

trolled regulation.– Document pack.

Recommended accessory– Safety group (SGB GCU compact, 15 70 46) with pres-

sure gauge, safety valve, automatic bleeding, filling cock,connection fittings).

Additional accessories see ROTEX price list.

4.4 Installing the Gas Combi Unit compact

4.4.1 Selecting the installation site The place of installation for the ROTEX GCU compact must meet the following minimum requirements.

Installation surface– The base must be level and smooth and have a sufficient

ground load-bearing capacity, of 1050 kg/m² plus safetyfactor. Install a pedestal if necessary.

– Observe the set-up dimensions (see section 4.1).

Installation room– There are no special conditions for ventilation of the installa-

tion room for operation independent of the ambient air (usinga concentric air/flue system).

– In the event of limited room-air independent operation and inthe event of room-air dependent operation, the installationroom must have a ventilation opening of at least 150 cm2 tothe outside. If the flue gas line goes via an installation shaft tothe outside, it must be rear ventilated (see section 4.2.2).

– For partial ambient air-independent and for ambient air-dependent mode, the installation room must be free fromaggressive vapours (e.g. hair spray, perchloroethylene, car-bon tetrachloride), heavy dust formation and high atmos-pheric humidity (e.g. washhouse).

– Outdoor installation is only possible to a limited extent. Thestorage tank must not be exposed to continuous directsunlight, as the UV radiation and the effects of the weatherwill damage the plastic.

– Installation room must be continuously protected from frost.

In some cases, the resonance in the flue system can amplify the noise at the mouth of the flue gas pipe. The noise level can be effectively reduced with the applica-tion of a silencer (E8 MSD, 15 45 78 bzw. E11 MSD, 15 45 79).

WARNING!

The ROTEX GCU compact is top heavy when not filled, it can tilt over during transport. This can pose a risk to persons or damage the machine.

Correctly secure the ROTEX GCU compact,transport carefully, use the handles.

A Handles (only required for transport)

B Cover screen

C Hose connection piece for safety overflow

D SpannerFig. 4- Contents of bag of accessories



Surface temperatures, minimum distance

– When operating independently of the ambient air with nomi-nal output, the design does not allow temperatures > 70°C on any component outside the unit panels. Therefore, no mini-mum distance is required to components made with flamma-ble materials.

– A minimum distance of 50 mm between the flue gas duct andflammable components should be maintained in a partialroom air-independent and ambient air-dependent mode (sep-arate flue gas/air intake line).

– Do not use or store easily inflammable and easily combustible substances directly next to the ROTEX GCU compact (mini-mum distance 1 m, see fig. 4-10).

4.4.2 Setting up the unit

Precondition– The installation site complies with the respective country-spe-

cific regulations, as well as the minimum requirements described in section 4.4.1.

Set-upRemove the packaging and dispose of it in an environmen-tally sound manner.Unscrew the threaded inserts (fig. 4-9, item G), onto whichthe carrier loops are to be attached, from the hot water storage tank.Thread the carrier loops (item A) through the threaded pieces (item G) and mount onto the available connections on the front and back of the hot water storage tank.

Carefully transport the ROTEX GCU compact to the erectionsite, use the handles.Install ROTEX GCU compact at the place of installation.– Recommended distances:

to the wall (s1/s2/s3/s4): see tab. 4-1To the ceiling (sD): 150 mm.

– Install close to the discharge point.

Install the connection lines to allow for the removal of thesound insulation hood (fig. 4-11).

WARNING!

The plastic wall of the storage tank of the ROTEX GCU compact can melt under the effects of external heat (80°C) and, in the extreme case, can catch fire.

Only install the ROTEX GCU compact with aminimum distance of 1 m to other heat sources(>80°C) (e.g. electrical heater, oil heater, chimney) and the material to be combusted.

CAUTION!

Wird die ROTEX GCU compact is not erected adequately lower the flat solar panels (the top edge of the storage tank is higher than the bottom edge of the solar panels), the unpressurised solar system in the outdoor area will be unable to drain completely.

Erect the GCU compact low enough, with a solarconnection, with regard to the flat solar panels(observe minimum gradient in the solar connecting lines)

WARNING!

The ROTEX GCU compact is top heavy when not filled, it can tilt over during transport. This can pose a risk to persons or damage the machine.

Correctly secure the ROTEX GCU compact,transport carefully, use the handles.

Fig. 4-9 Assemble the handles (for legend, see fig. 4-8)

Fig. 4-10 Minimum distances for the erection of the GCU compact (for dimensions, see tab. 4-1)


4 x Set-up and installation4.4.3 Remove the sound insulation hood

4.5 Air/flue system (LAS)

4.5.1 General instructions for flue system

Minimum requirementsObserve country-specific regulations and EN 15287 for the design and measurement of the flue gas system.

Basically, for the flue gas system, you can use each flue gas pipe according to EN 14471 with EU label, which meets the following minimum requirements:– Suitable for gas.– Suitable for flue gas temperatures of at least 120°C (temper-

ature class T120 or higher).– Suitable for at least 200 Pa overpressure (pressure class P1

or H1).– Humidity-resistant (condensation resistance class W).– Sufficiently corrosion-resistant (corrosion resistance class 1

or 2).The properties of the flue gas system must be identifiable on the installed system (nameplate in the installation room).

Type of connections– Directly backwards (fig. 4-1: SET H, 15 50 79.08).– At the side towards the back (fig. 4-2: SET K,

15 50 79.09).– Direct roof penetration (fig. 4-7, variant 2 and 3: SET L,

15 50 79.10).For other details and connection dimensions for the three ver-sions of the flue gas pipe, see section 4.5.3.

– Each flue gas line must be installed with a suitable testadapter for checking and setting the combustion values. TheROTEX LAS construction sets each include a test adapter(D8PA, 15 50 79.00 93).

Installation position and line height– The maximum permitted flue gas counter pressure is 200 Pa.

The pressure loss in the supply line must not exceed 50 Pa.– Angle of entry of the flue gas pipe into the chimney or instal-

lation shaft: at least 3°.– Slope for horizontal parts of the flue gas pipe: at least 3°.

Counter-slopes are not allowed at any point in the flue gaspipe.

– If the flue gas duct needs more than 3 deflections >45° for the flue gas duct, the maximum height for the flue gas ductreduces by at least 1 m per deflection (flue gas calculationsmay be needed).

– If the horizontal connecting piece is extended, the maximumpermitted height of the flue gas pipe is reduced by exactly that length.

– Flexible flue gas lines must not be used in horizontal connec-tion sections.

Flue gas system resistanceFor a safe burner start and stable flue gas values in the lower output range, a minimum resistance in the flue gas line is nec-essary, especially for liquid gas units.

After the initial burner start, the ROTEX GCU compact switches at first into the storage tank charging mode. In this mode, the burner blower runs with max. speed.

Switch the burner on (see chapter 15.2 "Emissionsmeasurement").Measure the resistance with a differential pressuremeasurement unit on the flue gas measurement locationbetween the flue gas and intake air measurement openings(differential pressure for the ROTEX GCU compact at least0.45 mbar).

If the differential pressure is not reached when the burnerblower is at maximum speed, a silencer will need to be fit-ted (E8 MSD, 15 45 78 or E11 MSD, 15 45 79)

The tab. 4-2 shows the maximum permissible height of the flue gas line to ensure that the ROTEX GCU compact can be op-erated in the rated power range.

Tab. 4-2 Maximum height for the flue gas duct in m

The characteristics for the flue gas calculation can be obtained from fig. 4-12 and chapter 15.1 "Data for designing the flue gas pipe".

WARNING!

There will be a risk of poisoning caused by flue gas escaping within enclosed rooms that are inadequately ventilated.

Install only approved flue gas systems.The stipulated ventilation and rear ventilation must be ensured, depending on the set up variant.Coverings of the flue gas mouth are not allowed.

Installation version

(according to fig. 4-7)

Max. permissible height of the fluegas line )

GCU compact315 / 515 324 / 524 533

11), 2, 3, 4 123) 153) 193)

5, 6 253) 273) 293)

1) Shaft cross-section at DN80: 135 mm x 135 mm

) Concentric flue gas-/supply line: DN80/125Design for natural gas (G20)

Fig. 4-1 Unscrew/loosen screws, lift the cover at the back and remove in a forwards direction.



The flue gas mass flow of the plant depends on the burner output of the ROTEX GCU compact.

4.5.2 Connecting a flue gas line

Requirements– The flue system fulfils the requirements described in

section 4.5.1.– The flue system fulfils any other required national or regional

safety requirements.– The ROTEX GCU compact is installed correctly.

Connection

Connect the ROTEX GCU compact to the flue gas systeminside the installation room (fig. 4-1 / fig. 4-2).For dimensions, see tab. 4-1.Place the nameplate of the flue gas pipe in the installationroom.

a

A Natural gas E/H (G20)B Natural gas LL/L (G25)C Liquid gas

mET Flue gas mass flowP Burner load

Fig. 4-12 Flue gas mass flow in dependence of the burner load ROTEX GCU compact (all types)

We recommend to use the associated ROTEX LAS-sets (see fig. 4-15). They satisfy all requirements and are also fitted with special acid-proof seals.

Fig. 4-13 Plan view GCU compact Flue gas connection to the rear with SET H (see section 4.5.3) - (for dimensions, see tab. 4-1)

AFig. 4-14 Plan view GCU compact Flue gas connection to the side with

SET K (see section 4.5.3) - (for dimensions, see tab. 4-1)

In some cases, the resonance in the flue system can amplify the noise at the mouth of the flue gas pipe. The noise level can be effectively reduced with the applica-tion of a silencer (E8 MSD, 15 45 78 bzw. E11 MSD, 15 45 79).

A A


4 x Set-up and installation4.5.3 Flue gas system kits

Fig. 4-15 Flue system kits * If needed** See tab. 4-1

(L) Flue gas connection left(R) Flue gas connection right(H) Flue gas connection rear



Additional kits– Flue gas connection to a duct system (rigid flue gas line

SET E or flexible flue gas line SET O)– Flue gas connection for exterior wall line (SET G)If necessary, additionally needed concentric LAS pipes for in-creased roof or ceiling heights, single wall PP pipes for chimney heights of more than 10 m or additional accessory components must be ordered.

4.6 Water connectionThe connections to the ROTEX GCU compact are on the top of the unit or on the front side ( solar return flow). Heating circuit and storage charge have a common inflow and return flow. The heating circuit for the storage charge is integrated at the factory and must not be connected separately.

Important information

For potable water lines, observe the stipulations of EN 806and the national regulations for potable water installation thatapply additionally.

To avoid a circulation line, install ROTEX GCU compact closeto the draw-off location. If a circulation line is absolutelyessential, it must be installed in accordance with theschematics in chapter 8.1 "Hydraulic system connection".

4.6.1 Connecting the safety group (SBG)

Assemble the components of the safety group SBG GCUcompact, as shown in fig. 4-17 or fig. 4-18, to the connectionof the ROTEX GCU compact.– Install the KSG-mini so that the pressure gauge can be

easily seen during filling.– There should be no hydraulic blocking elements between

the heat generator and the safety valve.– Any steam or heating water which may escape must be

diverted by a suitable blow-off line with constant gradientin a frost-protected, safe and observable manner.

– Install the line in such a way that the sound insulationhood of the ROTEX GCU compact can be placed withoutproblem after assembly.

– A diaphragm expansion vessel of adequate dimensionsand pre-set for the heating system must be connected tothe return line. There should be no hydraulic blocking ele-ments between the heat generator and the safety valve.

– Locate the diaphragm expansion vessel in an easilyaccessible place (maintenance, parts replacement).

BIVonly

CAUTION!

If the heat exchanger for charging the pressurised solar system (see fig. 3-3 / fig. 3-6, item 18 + 19) has an external heating unit (e. g. wood-burning boiler), too high a flow temperature can cause damage to or destroy the ROTEX GCU compact.

The flow temperature on the external heating unitshould be limited to max. 95°C.

CAUTION!

If the ROTEX GCU compact is connected to a cold water line, where steel pipes are used, chips can go into the special steel corrugated pipe heat exchanger and remain there. This can lead to contact corrosion damage and subsequently to leakage.

Flush the feed pipes before filling the heatexchanger.Install a dirt filter in the cold water supply.– SAS 1 ( 15 60 21)

In accordance with EN 12828 you must install a safety valve on or in the immediate vicinity of the heat ex-changer, with which you can limit the maximum permis-sible operating pressure in the heating system. There should be no hydraulic blocking elements between the heat generator and the safety valve.

Any steam or heating water which may escape must be diverted by a suitable blow-off line with constant gra-dient in a frost-protected, safe and observable manner.

A diaphragm expansion vessel of adequate dimensions and pre-set for the heating system must be connected to the ROTEX GCU compact. There should be no hy-draulic blocking elements between the heat generator and the diaphragm expansion vessel.

For the hydraulic connection of the GCU compact, ROTEX recommends using the safety group (SGB GCU compact, 15 70 46).

1.1 Pressure gauge1.2 Rapid bleeder1.3 Safety valve 3 bar

2.1 Connection diaphragm ex-pansion vessel

2.2 Connection KFE cock3 KFE cock

Fig. 4-16 Components for safety group SGB GCU compact


4 x Set-up and installation4.6.2 Connecting hydraulic lines

Check the cold water connection pressure (maximum 6 bar).– At higher pressure in the drinking water line, a pressure

reducer must be installed.Establish hydraulic connections at the ROTEX GCU compact.– The positions of the heating connections fig. 4-4 / fig. 4-6,

dimensions are shown in tab. 3-1.– Pay attention to the stipulated tightening torque (see

chapter 12.3 "Tightening torque").– Install the line in such a way that the sound insulation

hood of the ROTEX GCU compact can be placed withoutproblem after assembly.

– Connect the water for filling or refilling the heating systemas specified by EN 1717 to avoid contamination of drink-ing water by backwash.

Connect the blow-off line to the safety over-pressure valveand diaphragm expansion vessel in accordance withEN 12828.Carefully lag the hot water pipes to prevent heat loss.

– Water shortage protection: The overheating protection ofthe ROTEX GCU compact switches off the gas condensingboiler in case of heat deficiency and locks it. No additionalwater shortage protection is needed in the construction.

– Avoid damages caused by deposits and corrosion:Observe the relevant regulations of technology to preventcreation of corrosion products and deposits.Measures for desalination, softening or hardness stabilizationare necessary, if the filling and top-up water have a high totalhardness (>3 mmol/l - sum of the calcium and magnesiumconcentrations, calculated as calcium carbonate.

1 Boiler safety unit (KSG-mini) with safety valve 3 bar, rapid bleeder and pressure gauge

2 Connector for KFE cock + diaphragm expansion vesselFig. 4-17 Installation of safety group SBG GCU compact to type 3xx

Fig. 4-18 Installation of safety group SBG GCU compact to type 5xx (for legend, see fig. 4-17)

UK only!

CAUTION!

If filling or topping up the storage tank is done by means of the boiler filling and drain valve, a temporary filling loop must be used with the appropriate backflow prevention device in accordance with clause G24.2, Guidance to the Water Supply (Water Fittings) Regulations 1999.

WARNING!

There is a danger of scalding at hot water tempera-tures over 60°C. This is possible when using solar energy, if an external heater is connected, if Legionella protection is activated, or the hot water set temper-ature is set to be greater than 60°C.

Install a scald protection (domestic hot watermixing construction (e.g. VTA32, 15 60 16).



4.6.3 Connect the condensate drainThe condensate, forming during the cooling of the combustion gases in the boiler and in the flue gas system is dumped through the condensate tube into the storage container. By means of a permanent neutralisation filling it is neutralised and subsequently it is dumped into the sewer system through the safety overflow connection (fig. 4-19).

Direct condensation drain pipe (not included) with constantslope and with free inflow to the drains pipe.The complete outlet must not be lockable and must discharge the condensation and any medium leaking due to damage(drinking water, buffer or heating water) outwards visibly (e.g. hose to flow drain or transparent outlet pipe).In order to avoid puddling, make sure that no siphon is formedwith a flexible condensate drain hose up to the waste waterpipe.Check the condensate drain section for leakage.

4.7 Connection Control and Electrics

4.7.1 Instructions concerning electrical connection

All electronic control and safety devices of the ROTEX GCU compact are connected and tested and ready for use. Modifica-tions on the electrical installation are dangerous and prohibited. The operator alone shall bear responsibility for any resulting damage.

Mains connection, external temperature sensor and other op-tional applications (e.g. storage tank temperature sensor, circu-lation pump) still need to be connected to the boiler control panel.

4.7.2 Establishing the electrical connectionCheck the supply voltage (~230 V, 50 Hz).Switch the mains switch on the boiler control panel of theROTEX GCU compact to "OFF".Switch off the automatic fuse concerned on the junction boxof the domestic insulation (provide power supply).Remove the sound insulation hood (see section 4.4.3).Remove the right or left side housing cover (fig. 4-20).

Unlock the front panel and remove from the front (fig. 4-21).

Turn the front panel 180° and bring into the installationposition onto the control panel casing (fig. 4-22).Install the cabling into the regulation housing and establishthe electrical connections (fig. 4-23).

Fig. 4-19 Connection of the condensate overflow pipe

WARNING!

Live parts can cause an electric shock on contact and cause fatal burns or injuries.

Before beginning work on live parts, disconnectthem from the power supply (switch off fuse, mainswitch) and secure against unintentional restart.The electrical connection should only beperformed by electrical engineers in compliancewith valid standards and guidelines as well as thespecifications of the energy supply company.

Cables for external connections are laid underneath the right housing cover (mains connection, external tem-perature sensor, external components and control lines).

The left side housing cover has the cables for internal components.

Fig. 4-20 Dismount right housing cover.

Fig. 4-21 Unlock front panel.

Fig. 4-22 Open front panel and place in assembly posi-tion.

Fig. 4-23 Install the cabling into the regulation and es-tablish the electricalconnections.


4 x Set-up and installationControl panel circuit board

Tab. 4-3 Legend for fig. 4-24

Install the cabling leading outdoors into the strain reliefdevices in the right side of the housing (fig. 4-25). The sameprocedure applies on the left side of the housing for theinternal cabling in the event of an exchange.Re-install the side housing cover which was removed before(fig. 4-26).

Secure cables leading outdoors to the storage container(fig. 4-27).

Establish the mains connection between ROTEX GCUcompact and automatic fuse on the junction box of thedomestic power supply (see chapter 12 "Technical data",fig. 12-5).– Use an all-pole disconnecting main switch on the junction

box of the domestic power supply (separate isolator inaccordance with EN 60335-1).

– Ensure that the polarity is correct.After completing all electrical connection tasks, re-establishthe power supply to the automatic fuse concerned.

Fig. 4-24 Connection diagram of the circuit board connectors and cable colours of the factory-installed connection cables (for legend see tab. 4-3

Connections of the circuit board connectors:J2 GCU compact 3xx:

GCU compact 5xx: 3UV DHWJ3 N. b.J6 Mains connectionJ8 Sensors, switching contacts J9 FlowSensor (FLS1)J12 GCU compact 3xx: Not assigned

GCU compact 5xx: 3UVB1J13 CAN system busJ14 Circulation pump PZJ16 Room thermostat

Cable colours:bl bluebr brownge yellowgn greenn.a. Contact not

assigned

Mains supply 230 V, 50 Hz

A detailed description of the individual connections can be found in section 12.6.

Fig. 4-25 Install cables in chicanes.

Fig. 4-26 Install the right housing cover.

Fig. 4-27 Fasten cabling on the storage container.



4.7.3 Integrated heating circulation pump and 3-way-valve

The ROTEX GCU compact comes as standard with an integrated heating circulation pump and, according to the type:– GCU compact 3xx:

–– GCU compact 5xx:

– with a 3-way distribution valve (3UV DHW)– and a 3-way mixer valve (3UVB1).

The heating circulation pump and the 3-way valves are con-nected at the factory, the valve drive is inserted.

4.8 Temperature sensorInstructions concerning temperature sensors

The ROTEX GCU compact can regulate the flow temperature, dependent on the weather. The external temperature sensor (RoCon OT1), which is contained in the scope of delivery, is re-quired for this function.

The temperatures detected via the internal temperature sensors (flow and return flow temperature sensors, internal mixer sensors) are used to control the burner's output and to detect faults. The temperature sensors are already factory-connected and can be plugged directly to the respective sensor, if they need to be swapped.

The storage temperature sensor is also installed and con-nected at the factory (NTC resistance).

To regulate a mixer circuit you will need the Mixer Module (RoCon M1, 15 70 68), which includes the mixer circuit flow temperature sensor.

4.8.1 Connecting the exterior temperature sensor RoCon OT1

Choose a location at about one third of the building height(minimum distance from floor: 2 m) at the coldest side of thebuilding (North or North-East). Thereby, exclude the proximity of external heat sources (chimney, air shafts) and directsunshine.Place external temperature sensors in such a way that thecable exit points face downwards (prevents humidity ingress).

Connect the exterior temperature sensor to a twin-coresensor line (minimum diameter 1 mm2).Install the sensor line to the GCU compact.Connect the sensor line in the boiler control panel, at the plug of the connecting terminals 7 and 8 of the 12-pin sensor plugJ8 (see section 4.7.2).Insert the plug onto the switching panel PCB (fig. 4-29).

Close the switching panel.

On :1 Boiler flow (AB)2 Heater flow (A)3 Storage tank charging flow (B)

On 3UVB1:1 Boiler return (AB)2 Heater return flow (B)3 Storage tank charging return

(A)

4 3-way valve5.1 Valve drive

- 3UV DHW (black)- 3UVB1 (black)

5.2 Unlock button for the drive locking mechanism

5.3 Hand lever

Fig. 4-28 Design of the 3-way valve

CAUTION:

Using unapproved temperature sensors or those which do not match the device can cause considerablemalfunctioning in the regular operation of the ROTEX GCU compact, damaging the device control.

Use only the ROTEX temperature sensor available as an accessory.

Additional information and a detailed description can be found in the documentation "ROTEX Regulator RoCon BF". It is included in the scope of delivery of the GCU compact.

CAUTION!

The parallel routing of sensor and mains lines within an installation pipe can cause considerable malfunc-tioning in the regular operation of the ROTEX GCU compact.

Always lay the sensor line separately.

Fig. 4-29 Insert the sensor plug J8 onto the switching panel PCB


4 x Set-up and installation4.9 Connect the gas line, check the burner

setting for gas type

4.9.1 Important instructions for gas connection

Gas connection– Implement the gas connection according to the technical

rules for gas installation as well as the appropriate regulations of the country of destination and the gas supply company.

– A thermally triggered blocking device (TAE) and a gas flowmonitor (GSW) with a DVGW inspection symbol must be fit-ted. The TAE must comply with the test basis of DVGW-VP 301. The dimensions of the GSW must comply with the max-imum adjustable rated load of the device.

Gas type– The gas burner is factory-set to the gas type "Natural gas".– Observe the permissible gas inlet pressure (idle pressure)

(see tab. 12-5).

4.9.2 Connecting the gas line

Connect the factory installed corrugated gas connection hose (A) (pipe thread DIN EN 2999 Rp ½") without tension to thegas supply line.

4.9.3 Installing/removing the burner trimUndo the safety screws on the upper burner trim (fig. 4-31,item 1).Remove the upper burner trim.

Assembly is carried out in reverse order.

Pay attention to the stipulated tightening torque (see chapter 12.3 "Tightening torque").

DANGER OF EXPLOSION!

Escaping gas is a direct threat to human health and safety. Even a few sparks can cause very serious ex-plosions.

Before working on gas-conducting parts, alwaysclose the gas isolating valve first.If you can smell gas, ventilate the room thoroughly.Prevent sparks or flames from arising (e.g. nakedflame, electrical switches or mobile phone).Only heating specialists authorised and trained bythe gas or power supply company should beallowed to work on gas-conducting parts.

The standard corrugated gas connection hose can cause a pressure drop of up to 5 mbar. This will not hinder operation of the ROTEX GCU compact.

A Corrugated gas connection hoseFig. 4-30 Gas connection

1 Upper burner trim2 Lower burner trim

3 Safety gas control block

Fig. 4-31 Remove the upper burner trim



4.9.4 Checking the gas pre-installationCompare the available gas type with the set position of thesetting screw on the safety gas control block (fig. 4-32,item 1).– 1 = Natural gas– 2 = Liquid gas

The gas type must match.If the burner is not set to the available gas type, convert it to the new gas type (fig. 4-33) and mark it (see chapter 7.3 "Burner setting").

Turn the screw in the measuring connection inlet gaspressure (fig. 4-32, item 3.3) half a turn in an anti-clockwise direction.Vent the gas line in a professional manner.Insert the measuring hose of the pressure meter onto themeasuring connection inlet gas pressure (fig. 4-32, item 3.3).Check the inlet gas pressure.

If the gas inlet pressure lies below the permissible range(tab. 12-5), inform the responsible gas supply company. For liquid gas: Check the pressure regulator or set the burner to the permissible gas inlet pressure (see section 7). This adaptation must be appropriately labelled with a suitable burner settings sticker and an entry on the settings type plate (fig. 3-2 / fig. 3-5, item 33).

A conversion of the gas type must also be adjusted in the control. Observe the enclosed Control System Instructions!

3.1 Setting screw gas type3.2 Immersion coil3.3 Measuring connection IN inlet gas pressure3.4 Gas input3.5 Gas solenoid valve3.6 Voltage supply to gas solenoid valve3.7 Voltage supply to immersion coilFig. 4-32 Check the gas inlet pressure

Fig. 4-33 Set-up gas type


4 x Set-up and installation4.10 Optional connections

4.10.1 Mixer module RoCon M1The RoCon M1 mixer module can be connected to the ROTEX GCU compact, which is controlled via the electronic boiler control.

4.10.2 Room control RoCon U1For remotely setting operating types and set room temperatures from a different room, a separate room control RoCon U1 can be connected for each heating circuit.

4.10.3 Internet Gateway RoCon G1The Control can be connected to the Internet via the optional Gateway RoCon G1. This means that the ROTEX GCU compact can be controlled remotely via mobile phone (using an App).

4.11 Filling the systemDo not fill the ROTEX GCU compact until all installation activities have been completed, in the order shown as follows.

4.11.1 Check the water quality and adjust the pressure gauge

Observe the instructions concerning the water connectionaccording to section 4.6.

Before filling up the system for the first time, you will need to set the correct minimum pressure marking on the glass of the pressure gauge (in safety group SGB GCU, 15 60 13):

Rotate the pressure gauge glass in such a way that theminimum pressure mark corresponds to the system height+2 m (1 m water column corresponds to 0.1 bar).

4.11.2 Filling the hot water heat exchangerOpen the shutoff valve for the cold water supply pipe.Open the withdrawal tap connections for hot water to allowyou to set as large a draw-off rate as possible.Once water has been discharged from the tap connections,do not interrupt the cold water flow; this will ensure that theheat exchanger will be fully vented and that any impurities orresidue will be discharged.

4.11.3 Filling the storage tank

Without installed solar systemRemove the filling hose with backflush prevention (1/2") tothe connection "Solar inflow " (fig. 4-34, item 20).Fill the storage tank of the GCU compact until water beginsto escape from the overflow connection (fig. 4-34,item 23).Disconnect the filling hose with backflush prevention (1/2")again.

With installed solar systemMount the KFE cock (customer provision) to the das optionalthreaded connector (1" IG, 1¼" AG) of the solar regulationand pump unit ( ).Connect the filling hose with backflush prevention (1/2") tothe KFE cock installed before.Fill the storage tank of the GCU compact until water beginsto escape from the overflow connection (fig. 4-34,item 23).Disconnect the filling hose with backflush prevention (1/2")again.

A separate installation manual is included with this component. See the enclosed Control System Instruc-tions for the instructions on setting and operation.



CAUTION!

Escape of flue gas from the system will be damaging to health.

Before commissioning the ROTEX GCU compact,fill the storage tank container up to the overflowmark.

CAUTION!

Filling the storage tank container with excessive water pressure or with too high a flow speed can cause damage to the GCU compact.

Only fill with a water pressure <6 bar and a flowspeed <15 l/min.

UK only!

CAUTION!




20 Solar inflow23 Safety overflowGc GCU compactFig. 4-34 Filling buffer storage tank - without connected DrainBack solar

system

Gc 5xx Gc 3xx


4 x Set-up and installation4.11.4 Filling the heating system and the storage tank

charging circuit

1. Engage the hand lever (fig. 4-35, item 5.3) of the 3-way valve(3UVB1/3UV DHW) into the centre position (as-deliveredcondition: only possible when de-energised).

2. Connect the filler hose (fig. 4-35, item 1) with flow-backpreventer (1/2") to the KFE cock (fig. 4-35, item 2) and securewith a hose clip to prevent it from coming off.

3. Open the water cock (fig. 4-35, item 6) in the supply line.

4. Open the KFE cock (fig. 4-35, item 2) and observe thepressure gauge (fig. 4-35, item 8).

5. Fill the system with water until the marking of the systemoverpressure is roughly in the centre of the green range of the pressure gauge display.

6. Close KFE cock (fig. 4-35, item 2).

7. Vent the entire heating network (open the system controlvalves).

8. Check the water pressure on the pressure gauge again andtop up with water via the KFE cock (fig. 4-35, item 2).

9. Close the water cock (fig. 4-35, item 6) in the supply line.

10. Disconnect the filling hose (fig. 4-35, item 1) with backflushprevention from the KFE cock (fig. 4-35, item 2).

DANGER!

During the filling procedure, water may escape from any leaky areas which can cause an electric shock if it comes into contact with live parts.

Disconnect the GCU compact before filling.After filling for the first time and before switchingthe GCU compact at the mains switch, check thatall electrical parts and joints are dry.

WARNING!

Contamination of drinking water endangers the health.

When filling the heating system prevent any back-flow of heating water into the drinking water piping.

Fig. 4-35 Fill the heating system and the storage tank charging circuit (shown on the GCU compact 5xx)

1 Filling hose with backflush prevention

2 KFE cock3 Ball cock heating system-

inflow4 Ball cock heating system -

return flow5.1 Valve drive5.2 Unlock button for the drive

locking mechanism

5.3 Hand lever6 Water cock7 Automatic bleeder8 Pressure gauge

3UV DHW3-way distribution valve

3UVB13-way mixer valve


In the as-delivered condition, the 3-way valves (3UVB1/3UV DHW) are in the filling position. The hand lever (fig. 4-35, item 5.3) is in a latchedmiddle position. The 3-way valve partly releasesboth flow paths.

If the hand lever (fig. 4-35, item 5.3) faces away from the valve body (valve setting AB-B) or towards the valve body (valve setting AB-A), the 3-way valve will need to be brought into the centre position before filling (see work step 2 and the enclosed operating instruc-tions "ROTEX Control RoCon BF").

The centre position is only stable when the 3-way valve is de-energised. The 3-way-switch valve unlocks automatically when the voltage at the drive motor for the valve position AB-A is applied.

ZB_RoCon_VentFkt (008.1534699)

11.

ZB_RoCon_VentFkt (008.1534699)

5 x Start-up


5 Start-up

Incorrect start-up makes the manufacturer's guarantee for the unit void. If you have questions, please contact our Technical Customer Service.

5.1 Initial start-upAfter the ROTEX GCU compact has been erected and fully con-nected, it can be put into service by skilled staff.

5.1.1 Requirements– The ROTEX GCU compact is fully connected.– The burner trim is closed and is sealed tight.– The heating and hot water system are filled and charged with

the right pressure.– The storage tank is filled to the overflow point.– The control valves of the heating system are open.

5.1.2 Checks before start-upCheck all connections for leakage.Check all the items in the enclosed checklist (see section 5.2- Before start-up). Log the test results on the checklist.Only when all items on the checklist can be answered withYes should the ROTEX GCU compact be put into service.

5.1.3 Start-up1. Open the gas stopcock.

2. Switch on the mains switch. Wait for the start phase.– In case of starting problems, see chapter 10.

3. Configure the heater system from the RoCon BF control.– For setting and explanations, see the enclosed operating

instructions "RoCon BF Control" -> chapter "Initial start-up".

– Enter modified setting values in the corresponding table in the operating instructions of the RoCon BF control.

4. First automatic calibration:From the RoCon BF control, select the programme[Emission Measurement] -> [Full Load](see chapter 15.2), but do not confirm.

– Make sure heat can dissipate into the heating networkduring the calibration.

– In the event of burner starting problems, seechapter 7.3.4.Automatic calibration of the GCU compact and adaption of the gas valve complete.Calibration and adaption are complete 2 minutes after the burner symbol appears in the display. GCU compact runs under full load.End programme [Emission Measurement].Burner blower switches off.After the burner blower has come to a stop, switch off themains plug on the boiler control panel.GCU compact switches off.Wait 20 seconds before switching the mains switch onagain. Wait for the start phase.

5. Second automatic calibration and performance of flue gas measurement:

From the RoCon BF control, select the programme[Emission Measurement] -> [Full Load](see chapter 15.2), but do not confirm.

– Make sure the heat can dissipate into the heating network during emission measurement.

– In the event of burner starting problems,see chapter 7.3.4.Automatic calibration of the GCU compact and adaption of the gas valve complete.Calibration and adaption are complete two minutes after the burner symbol appears. GCU compact runs under full load.Use the glue gas analyzer to check the burner settingsand compare them with tab. 5-1 to tab. 5-3.

a) If the O2/CO2 concentrations lie within the permissiblevalues:No further measures are required.

b) If the O2/CO2 concentrations lie outside the permissiblevalues:Carry out a 100 % calibration and adjust the [Drop Io-base] in such a way that the setting range is reached (See chapter 7.3.4) and repeat the measurement.Document the measured values in the "Installation certifi-cation" and in the operating manual.

WARNING!

A ROTEX GCU compact that is installed or started in-correctly may not operate properly and is dangerous for the health and safety of individuals.

Only heating engineers, authorised and trained bygas and energy supply companies are allowed tostart up the ROTEX GCU compact.

CAUTION!

A ROTEX GCU compact not put into operation properly can lead to damage to property and the envi-ronment.

Observe the regulations in VDI 2035 in order toavoid corrosion and deposits.Measures for desalination, softening or hardnessstabilization are necessary, if the filling and top-upwater has a high total hardness (>3 mmol/l - sumof the calcium and magnesium concentrations,calculated as calcium carbonate).– We recommend Fernox scale and corrosion

protection agent KSK ( 15 60 50).During the plant operation, the water pressure atthe manometer (green area) must be checked atregular intervals. If necessary, readjust by toppingup.


5 x Start-up

6. In the programme [Emission Measurement] select the setting[Base Load] (see chapter 15.2), but do not confirm.– Make sure the heat can dissipate into the heating network

during emission measurement.Use the flue gas analyser to check the burner settings and compare them with tab. 5-1 to tab. 5-3.

a) If the O2/CO2 concentrations lie within the permissiblevalues:No additional measures are required.

b) If the O2/CO2 concentrations lie outside the permissiblevalues:Carry out 100% calibration and adjust the [Drop Io-base] in such a way that the setting range is reached (see chapter 7.3.4) and repeat the measurement from step 5.Document the measured values in the "Installation certifi-cation" and in the operating manual.

7. End programme [Emission Measurement].

8. Set manual mode from the RoCon BF control (see operatinginstructions "RoCon BF Control").

9. Check the resistance in the flue gas line (see chapter 4.5).

5.1.4 After start-upMount the sound insulation hood (see chapter 4.4.3).Check all items on the "Checklist after start-up" (seesection 5.2).Log the test results on the checklist.Only when it is possible to answer all items on the checklistwith Yes, is it allowed to hand over the ROTEX GCU compact to the operator.

CAUTION!

The firing unit is programmed to take into account the ageing of the components. A 100 % calibration of the firing unit can have a negative impact on the above even if the exhaust setting values (tab. 5-1 to tab. 5-3) are adhered to.

Only carry out a calibration of the firing unitwhen the exhaust setting values are notadhered to, or when a mechanical changewas carried out, e.g. by replacing thecomponent with original ROTEX spareparts.

Type GCU compact 315 / 515 (BIV)Gas type

(Prüfgas)**Burner load O2-content

in %CO2-content

in %Natural gas E/H

(G20)Base Load 4.0 - 5.5 8.6 - 9.5Full Load 4.0 - 5.4 8.7 - 9.5

Natural gas LL/L (G25)

Base Load 4.0 - 5.5 8.5 - 9.3Full Load 4.0 - 5.4 8.5 - 9.3

Propane* (G31)


* Liquid gas setting** Compare with the information on the yellow sticker attached to the burner

housing

Tab. 5-1 Start-up control values for GCU compact 315 and GCU compact 515 for various gas types

Type GCU compact 324/ 524 (BIV)Gas type (test

gas)**Burner load O2-content

in %CO2-content

in %Natural gas E/H




Propane* (G31)



housing

Tab. 5-2 Start-up control values for GCU compact 324 and GCU compact 524 for various gas types

Type GCU compact 533 (BIV)Gas type (test

gas)**Burner load O2-content

in %CO2-content

in %Natural gas E/H




Propane* (G31)



housing

Tab. 5-3 Start-up control values for GCU compact 533 for various gas types

5 x Start-up


5.2 Checklists for start-up

Checklist before start-up1st. Is the ROTEX GCU compact correctly set up according to an admissible set up variant and without visible

damages?Yes

2. Combustion air supply secured? Yes3. Adequate ventilation and extraction in the heating room with limited room-air independent (separate flue

gas/intake air) or room-air dependent operation?Yes

4. Does the mains connection conform to the specifications? Yes5. Is the mains voltage 230 V, 50 Hz? Yes6. Flue gas line connected correctly with a consistent gradient (at least 3°) and no leaks? Yes7. Storage tank topped up with water to overflow, condensate drain line connected correctly and leakproof? Yes8. On restoration: Heat distribution network flushed out? Sludge separator fitted in heating return? Yes9. Is the diaphragm expansion tank mounted according to specifications and of the requisite size? Yes10. Is the safety valve connected to a safe free drain? Yes11. Has the quality of the filling water been checked and has any necessary water preparation been carried out? Yes12. System water pressure within prescribed range? Yes13. Are boiler and heating system vented? Yes14. Are all sensors connected and correctly positioned? Yes15. Mixer group, mixer module and mixer circuit sensor (optional) connected correctly? Yes16. Room controller (optional) correctly connected to the PCB? Yes17. Is the gas connection installed according to specifications, expertly and correctly?? Yes18. Has the gas line been vented expertly and checked for leaks? Yes19. Do the gas type and gas inlet pressure correspond to the values indicated on the boiler sticker? YesThe system may only be started up if all questions can be answered with "Yes".

Checklist after start-upA Is the heating circulation pump running, does the heater get hot? YesB Is the flow pressure for the gas type within the permitted range? YesC Has the screw for the gas pressure test point been retightened and are they leakproof? YesD Has the resistance of the flue gas pipe been measured and if so, is the measured resistance higher than the re-

quired minimum resistance?Yes

E Have the burner settings been checked by using a flue gas analyser and do the values lie within the stipulated range?

Yes

F Has the sound insulation hood been re-installed after start-up? YesG Have the connectors been inserted into the 3-way valves after start-up? YesThe system may only be handed over to the user/owner if all questions can be answered with "Yes".

Fill out the enclosed installation and instruction form as well as the first pages of the operating manual together with the operator.


6 x Control unit6 Control unit

6.1 Operating elements on the boiler control panel

Mains switchSwitch on and off the ROTEX GCU compact. When the heating system is on, the mains switch is illuminated green.

Operating section on the RoCon B1The operating section is equipped with a coloured backlit clear text.

The colour of the backlighting indicates the operational status and the programming mode:

In normal system operation, the rotary switch should be in the po-sition "Info".

In the display on the controller the most important system temper-atures and operational conditions are displayed.

The ROTEX GCU compact is fitted with the ROTEX RoCon BF Control. The fitted digital control system serves to actuate a direct heating circuit and a storage tank charging circuit.

It can be extended in many ways with accessory components.

A detailed description can be found in the documentation of the ROTEX RoCon BF Reglator.

1 Mains switch2 Operating part RoCon B13 Clear text display4 Rotary switch5 Setting: Info

6 Setting: Operating Mode7 Setting: Set Temp Day8 Setting: Set Temp Night9 Setting: DHW Set Temp10 Setting: DHW Reheating

11 Setting: Time Program12 Setting: Configuration13 Setting: System14 Rotary button15 Exit button (jump back, Special Level, fault

rectification function)Fig. 6-1 Operating elements on the boiler control panel

Malfunctions are generally indicated by a fault code and a clear text fault message on the display.

For troubleshooting instructions refer to chapter 10"Faults and malfunctions".

White: Standard lighting, normal operational display.Red Fault status, depending on the type of fault the boiler

continues to operate with restrictions.Green: Programming mode with operator authorisation.Blue: Programming mode with expert authorisation.

Additional information and a detailed description can be found in the documentation "ROTEX Regulator RoCon BF". It is included in the scope of delivery of the GCU compact.

6 x Control unit


6.2 Replacing the operating section RoCon B1

Removing the operating sectionRelease the lugs on both sides of the operating section bysliding in a small flat bladed screwdriver in (fig. 6-2, item 1) and pull the operating section out to the front.To remove completely, unplug the communication cable(fig. 6-2, item 3) on the reverse side of the operating section.

Fitting the operating sectionPlug in the communication cable on the back of the operatingsection.Slide the operating section into the switching panel cut-outuntil the lugs click in place again.

6.3 Changing the sensorsInternal sensors (fig. 6-3) can be changed without having to open the boiler control panel.WARNING!

Live parts can cause an electric shock on contact and cause life-threatening burns and injuries.

Before beginning work on live parts, disconnectthem from the power supply (switch of fuse, mainswitch) and secure against unintentional restart.

A Front viewB Rear view

1 Operating section RoCon B12 Plug connection for commu-

nication cable3 Communication cable

Fig. 6-2 Removing/fitting the operating section

A

B

WARNING!

Live parts can cause an electric shock on contact and cause life-threatening burns and injuries.

Before beginning work on the ROTEX GCUcompact disconnect it from the power supply(switch off the fuse, main switch) and secureagainst unintentional restart.

1 Automatic bleeder2 Flow temperature sensor tV13 Pressure sensor4 Heat cell flow5 Heat cell return flow6 Return temperature sensor tR27 Heating circulation pump8 FLS1 flow sensor with return temperature sensor tR1Fig. 6-3 Position of the sensors at the boiler


6 x Control unit6.3.1 Changing the flow temperature sensor / return

temperature sensor and pressure sensor

1. Remove the sound insulation hood (see chapter 4.4.3).

2. Remove the upper burner trim (see chapter 4.9.3).

3. Remove the connector from the sensor(s) to be removed(fig. 6-3, item 2).

4. Unscrew the sensor(s) to be replaced with an open-endedspanner SW 15.

5. Screw in the new sensor(s) and attach the cable(s) withconnector.– The connectors are shape-coded. Do not force the con-

nector!– Pay attention to the stipulated tightening torque (see

chapter 12.3 "Tightening torque").

6.3.2 Changing the internal mixer sensor for heating support

The internal mixer sensor tV2 for the heating support function "ISM" is mounted underneath the heat insulation of the hydraulic line components. The fig. 6-4 shows which components need to be removed to reach the internal mixer sensor.

1. Remove the sound insulation hood (see chapter 4.4.3).

2. Remove the heat insulations and valve drive 3UV DHW(fig. 6-5 to fig. 6-7).

WARNING!

There is a danger of scalding from heating water.

The sensor(s) are directly connected to the pres-surised heating water.

Before removing the sensor(s), close the ballcocks at the boiler flow and boiler return line anddepressurise the machine via the KFE cock.

WARNING!

Using an unauthorised temperature sensor causes thesafety and control functions to function incorrectly.

Replacement parts must at least satisfy thetechnical requirements defined by the manufac-turer. This is the case, for example, with originalspare parts.

WARNING!

There is a danger of scalding from heating water.

The sensor(s) are directly connected to the pres-surised heating water.

Before removing the sensor(s), close the ballcocks at the boiler flow and boiler return line anddepressurise the machine via the KFE cock.

1.A Heat-insulating jacket1.B Heat-insulating jacket2 Heat-insulating jacket3 Valve drive 3UV DHW

4 Heat-insulating jacket5 Heat-insulating jacket6 Heat-insulating jacket

Fig. 6-4 Components to be removed to disassemble the internal mixer sensor

Fig. 6-5 Remove the heat insulations - 1.+ 2.

Fig. 6-6 Remove the valve drive and heat insulation - 3.+ 4.

6 x Control unit


3. Remove the connector from the internal mixer sensor tV2 (fig. 6-8, item 2).

4. Unscrew the internal mixer sensor with open-ended spannerSW 15.

5. Screw in the new internal mixer sensor and attach thecable(s) with connector.– The connectors are shape-coded. Do not force the con-

nector!– Pay attention to the stipulated tightening torque (see

chapter 12.3 "Tightening torque").

6.3.3 Changing the storage tank temperature sensorThe storage tank temperature sensor is attached directly to con-necting terminals 9 and 10 of the 12-pin sensor connector J8 in the boiler control panel (see chapter 12.6).

1. Open the boiler control panel and remove the connector J8from the switching panel PCB (see chapter 4.7.2).

2. Pull out the storage tank temperature sensor from the sensorimmersion sleeve at the storage tank.

3. Bend the pressing springs on the new sensor and push thenew sensor into the sensor immersion sleeve.The insertion depth is marked on the ROTEX storage tank bya coloured marking, depending on the storage tank type.

4. Connect the sensor cable to the connector on the connectingterminals 9 and 10 of the 12-pin sensor connector J8.

5. Plug the connector into the switching panel PCB and closethe boiler control panel.Make sure there is sufficient tension relief on the sensorcable.

Fig. 6-7 Remove the heat insulations - 5.+ 6.

1 Internal mixer sensor tV2Fig. 6-8 Change the internal mixer sensor

For further information on fitting the storage tempera-ture sensor see: "Storage temperature sensor“ installa-tion instructions.

Fig. 6-9 Changing the storage temperature sensor


7 x Gas burner7 Gas burner

7.1 Structure and brief description

Fig. 7-1 Gas burner of the GCU compact - exploded view drawing (for the legend, see tab. 7-1)

1 Air inlet collecting pipe2 Safety screw (Venturi nozzle)3 Venturi nozzle4 O-Ring5 4x fixing screws (flue gas collector/ boiler body) 6 flue gas collector7 seal for flue gas collector8 8x fixing screws (flue gas collector /basic frame) with boiler basic

frame 9 Boiler body10 O-Ring (Venturi nozzle-gas intake)11 Safety clamp12 4x fixing screws (burner blower / burner flange)13 4x fixing screws (burner flange/ boiler body) 14 4x fixing screws (burner blower / blower adapter)15 Seal (burner blower / blower adapter)16 Burner flange seal17 Burner adapter18 4x fixing screws (ignition electrodes + ionisation electrode)


1 Ionisation electrode2 Burner adapter3 Burner flange4 Ignition electrode5 Burner blower6 Boiler body7 Gas connection G ½" female

with connected gas hose8 Safety gas control block

9 Condensate pipe10 Flue gas collector11 Gas connection line12 Air inlet collecting pipe13 Venturi nozzle14 Ignition transformer15 2x fixing screws (safety-gas

control block / gas connectionline)

Fig. 7-2 Gas burner of the GCU compact - Side view

7 x Gas burner


Controlling the burner outputThe control determines the required flow temperature based on the set operating parameters and passes it to the firing unit of the gas burner. The combustion controller calculates the required burner output from the target value and the values from the flow and the return flow temperature sensor. The determined output is passed to the burner fan as a PWM signal. The burner fan imme-diately adjusts the gas fan speed and as such the combustion air flow. The gas controller controls the gas volume accordingly.

Firing unit CM434The microprocessor-controller gas firing unit CM434 controls and monitors the firing programme and the temperature sensors for the flow and return temperature.

7.2 Safety functionFault shutdown and malfunction indicatorYou can find an overview of the interlocking- and temporary fault shutdowns in chapter 10.3, tab. 10-2 to tab. 10-4).

A fault is displayed:– by the red backlight in the display,– by a clear text fault message with the fault code in the display

on the control section.

Unlocking the burner

Interlocking faults detected by the automatic firing can only be reset manually directly on the boiler.

Requirements: The cause of the malfunction is rectified, the burner is electrically connected.

1. Switching ROTEX GCU compact on.

2. Push the Exit button (fig. 6-1, item 15) for at least 5 secs.Menu "Special Level" is displayed.

3. Select the "FA failure" level with the rotary switch.Error code and prompt "Reset?" is displayed.

4. Select "Yes" with the rotary switch.

5. Confirm the changes with a brief push of the rotary switch.Fault is reset.

6. Cancelling and jump back by pushing the Exit button again.

7. If there are several successive fault shutdowns, check theheating system (e.g. flue system, fuel supply).

7.3 Burner setting

Tab. 7-2 Possible adjustment ranges

If changes have been made to the power settings of the burner or if it has been converted to a different type of gas, this must be logged in the operating manual and entered on the setting type plate (fig. 7-3).

The changeover must be provided with the date of implemen-tation and the signature of the installer.

An interlocking fault can only be reset manually from the controller of the GCU compact (see chapter 10.4).

With a temporary fault shutdown the burner is switched off for at least 60 secs.

When the above conditions are back in the normal working range, a burner release is carried out automat-ically.

The cause of the last fault is saved in the unit and can be reconstructed on restarting the unit, even after power failure.

If more than 5 faults are reset within a 15 minute period, the fault code E96 is displayed. Another release in then only possible after 15 mins.


Escaping gas is a direct threat to human health and safety. Even a few sparks can cause major explo-sions.

Before working on gas-conducting parts, alwaysclose the gas isolating valve first.If you can smell gas, air the room thoroughly.Prevent sparks or flames from arising (e.g. nakedflame, electrical switches or mobile phone).Only heating specialists authorised and trained bythe gas or power supply company should beallowed to work on gas-conducting parts.

CAUTION!

An inappropriate setting of the oil burner can lead to a prohibited level of pollutant emissions, heavy contam-ination and increased oil consumption.

Burner setting should be carried out only byauthorised and recognised heating engineers.

TypeGCU compact

Blower type (Manufac-

turer)

Burner surface

Adjustable load in kW

315 / 515

Type 118 Type A

6.5 - 15.7324 / 524 6.5 - 25.3

533 6.5 - 32.5 (6.5 -30.0)*

* Liquid gas setting

Fig. 7-3 Settings type plate


7 x Gas burner7.3.1 Setting values 7.3.2 Establishing access to the burner

Remove the sound insulation hood (see chapter 4.4.3).Remove the upper burner trim (see chapter 4.9.3).

7.3.3 Checking and setting the burnerThe gas burner is factory-set to the gas type "Natural gas". The stipulated gas inlet pressure can be found in tab. 12-5.

The RoCon BF control cab be used to set up the GCU compact to the function [Emission Measurement] under [Full Load] and [Base Load]. The flue gas values are inspected with a flue gas analysis device.

Auxiliary resources– Flue gas analysis device.– Pressure meter for measuring gas pressure.

Checking and settingObserve the sequence!

1. Check whether the burner is pre-set to the correct gas typeand the correct gas inlet pressure (see also section 4.9.4).

2. Turn the screw in the gas inlet pressure measuringconnection (fig. 4-32, item 3.3) anticlockwise by half a turnand push up the measuring hose of the pressure meter.

3. Open the gas stopcock.

4. Measure the gas inlet pressure (idle pressure) and compareit to the target value (see tab. 12-5). Leave the measuringinstrument connected.

If the gas inlet pressure (resting pressure) is outside theset value range: Inform your gas supply company or check the pressure regulator (for liquid gas).

5. Open the heating valves.

6. Switch on ROTEX GCU compact with main switch.

7. Start the [Emission Measurement] on the RoCon BF Controlof the GCU compact and select the setting [Full Load], butdo not confirm.

Type GCU compact 315 / 515 (BIV)Gas type (test

gas)**Burner load

in kW at "Full Load"

O2-contentin %

CO2-contentin %

Set + - Set + -Natural gas E/H (G20)

15.7 4.6 0.6 0,2

9.2 0.1 0.3

Natural gas LL/L (G25) 9.0 0.1 0.3

Propane* (G31) 10.7 0.3 0.5

* Liquid gas setting** Compare with the information on the yellow sticker attached to the burner housing

Tab. 7-3 Set exhaust setting values for GCU compact 315 and GCU compact 515 for various gas types

Type GCU compact 324/ 524 (BIV)Gas type

(Prüfgas)**Burner load


O2-contentin %

CO2-contentin %


25.3 4.3 0.6 0.2

9.3 0.1 0.3


Propane* (G31) 11.0 0.3 0.5


Tab. 7-4 Set exhaust setting values for GCU compact 324 and GCU compact 524 for various gas types

Type GCU compact 533 (BIV)Gas type

(Prüfgas)**Burner load


O2-contentin %

CO2-contentin %


32.54.0 0.6 0.2

9.5 0.1 0.3


Propane* (G31) 30.0 11.1 0.3 0.5


Tab. 7-5 Set exhaust setting values for GCU compact 533 for various gas types

Type GCU compact 3xx / 5xx (BIV)Gas type

(Prüfgas)**Burner load in

kWat "Base Load"

O2-contentin %

CO2-content in %


6.5 4.4 0.9 0.4

9.3 0.2 0.6


Propane* (G31) 10.8 0.3 0.6


Tab. 7-6 Set exhaust setting values with "Base Load" for all GCU compact types for different gas types

If the burner does not start, even with the power and gas supply properly connected and with the flue gas path free, the cause for this fault must be found and rec-tified (see chapter 7.3.4).

7 x Gas burner


8. Connect the flue gas analysis unit.

9. Check flow pressure.The gas inlet flow pressure must not fall essentially belowthe idle pressure minus the pressure loss in the gas con-nection hose (see tab. 12-5). If the flow pressure is too low, the burner output also drops.

10. If the measured flue gas values do not change anymore (forthe soonest 2 min after the start of the burner), measure theCO2-content and the O2-content. Compare the measuredvalues with the specified setting values (see section 7.3.1).a) If the O2/CO2 concentrations lie within the permissible

values:No further measures are required.

b) If the O2/CO2 concentrations lie outside the permissiblevalues:Carry out 100 % calibration and adjust the [Drop Io-base] in such a way that the setting range is reached, see section 7.3.4 and repeat the measurement.

11. In the programme [Emission Measurement] choose thesetting [Base Load], but do not confirm.

12. If the measured flue gas values do not change anymore (forthe soonest 2 min after the start of the burner), measure theCO2-content and the O2-content. Compare the measuredvalues with the specified setting values (see section 7.3.1).a) If the O2/CO2 concentrations lie within the permissible

values:No further measures are required.

b) If the O2/CO2 concentrations lie outside the permissiblevalues:Carry out 100 % calibration and adjust the [Drop Io-base] in such a way that the setting range is reached, see section 7.3.4 and repeat the measurement.

Changeover from natural gas to liquid gas

1. Turn the setting screw Gas/Air mix (fig. 4-32, item 3.1) toPosition 2.

2. Change the gas type in the RoCon BF Control as follows:Place the rotary switch in the "Configuration"position.An overview is displayed.Select the "SCOT config" level with the rotary switch.An overview is displayed.Using the rotary switch, select the parameter [Gas type]and confirm.Using the rotary switch, select the "Liquid gas" value.Confirm the changes with a brief push of the rotary switch.Change has been accepted. Jump back to previous dis-play.

3. Enter the gas type changeover on the setting type plate andin the operating instructions and confirm with your signature.

4. Affix a device sticker for the gas conversion onto the burnerhousing.

5. Carry out commissioning as per chapter 5.1.3. In the event ofstarting problems, see section 7.3.4.

More detailed explanations and possible setting values for these parameters can be found in the operating instructions "ROTEX RoCon BF Control".

Resetting from Liquid petroleum gas to natural gas1. Turn the setting screw Gas/Air mix (fig. 4-32, item 3.1) to

Position 1.

2. Change the gas type in the RoCon BF Control as follows:Place the rotary switch in the "Configuration"position.An overview is displayed.Select the "SCOT config" level with the rotary switch.An overview is displayed.Using the rotary switch, select the parameter [Gas type]and confirm.Using the rotary switch, select the "Natural gas" value.Confirm the changes with a brief push of the rotary switch.Change has been accepted. Jump back to previous dis-play.

3. Enter the gas type changeover on the setting type plate andin the operating instructions and confirm with your signature.

4. Affix a device sticker for the gas conversion onto the burnerhousing.

5. Carry out commissioning as per chapter 5.1.3. In the event of starting problems, see section 7.3.4.

More detailed explanations and possible setting values for these parameters can be found in the operating instructions "ROTEX RoCon BF Control".

7.3.4 Starting problems - calibrate the firing unit, starting output burner blower and setting the gas volume

The factory-set starting output usually provides a problem-free, quiet burner start.

The starting output of the burner blower is factory-set.

If during the starting process an obvious deflagration or whistling sound occur, or several starting attempts are necessary on a regular basis, a slight change in the starting output may remedy the occurrences.

For deflagrations: Reduce the starting output or gas vol-ume.In the event of difficulties starting such as burner whistling or flame formation: Increase the starting output or gas vol-ume.

ROTEX recommends the following procedure for rectifying general starting problems:

Air inlet collecting pipe (fig. 7-2, item 12) must be inserted into the Venturi nozzle (fig. 7-2, item 13).

In the event of starting problems, the starting output of the burner blower can be changed by the heating expert and the firing unit can be re-calibrated automat-ically.

More detailed explanations and possible setting values can be found in the operating instructions "ROTEX RoCon BF Control". This documentation is included in the scope of delivery.


7 x Gas burnerCalibration of the firing unit

1. Switching the ROTEX GCU compact off and on again.

2. Place the rotary switch in the "Configuration" position.An overview is displayed.

3. Select the "SCOT config" level with the rotary switch.An overview is displayed.

4. Using the rotary switch, select the parameter [100%Calibration] and confirm.

An overview is displayed.

5. Using the rotary switch, select the parameter [Drop Io-base]and confirm.

Calibration running. After calibration is complete, anadjustment range of -5 to +10 is displayed.

6. Connect the flue gas analysis unit to the GCU compact.

7. Using the rotary switch, adjust the parameter [Drop Io-base]so that the flue gas values lie in the target value range.

8. Confirm the changes with a brief push of the rotary switch.Calibration is complete.Burner starts without problems: No further measures arerequired.Burner start has faults: Check and, where necessary, adjust the starting output of the burner.

Checking, adjusting the starting output of the burnerThe setting of the parameter [Corr power start] is directly asso-ciated with the structural design.



3. Using the rotary switch, select the parameter [Corr powerstart] and confirm.

Current value is displayed.

4. Using the rotary switch, adjust the parameter [Corr powerstart].

5. Confirm the changes with a brief push of the rotary switch.


7. Generate a burner demand (e.g. heating operation).Burner starts without problems: No further measures arerequired. Enter the performance changes in the opera-tional handbook and confirm with your signature.Burner start has faults: Re-adjust the starting output and, adjust the gas volume where necessary.

Adjusting the gas volume at the burner startThe gas volume at burner start can be set up by adjusting the pa-rameter [Corr qGas start].



3. Using the rotary switch, select the parameter [Corr qGasstart] and confirm.


4. Using the rotary switch, adjust the parameter [Corr qGasstart].



7. Generate a burner demand (e.g. heating operation).Burner starts without problems: No further measures arerequired.Burner start has faults: chapter 10 "Faults and malfunc-tions".

With starting problems after a replacement of the safety gas control block:

By setting the parameter [CL - Offset CES] the starting configu-ration of the safety gas control block can be adjusted for the first burner start.



3. Using the rotary switch, select the parameter [CL - OffsetCES] and confirm.


4. Using the rotary switch, adjust the parameter [CL - OffsetCES].



7. Generate a burner demand (e.g. heating operation).Burner starts without problems: No further measures arerequired.Burner start still has faults after several corrections: see chapter 10 "Faults and malfunctions".

In case of noise problems (whistling, humming, or the like), ad-justing the starting parameters described previously (startingoutput, gas volume burner start) can provide a remedy.

When operating with natural gas, removing the air inlet collecting pipe (fig. 7-2, item 12) may also be successful.

Disruptive noise caused by resonance can be reduced effectively using a silencer (see chapter 4.2).

CAUTION!

The firing unit is programmed to take into account the ageing of the components. Calibrating the firing unit can still have a negative impact on this even when complying with the exhaust setting values (tab. 5-1 to tab. 5-3).

Only carry out a calibration of the firing unit whenthe exhaust setting values are not adhered to, orwhen a mechanical change was carried out, e.g.by replacing the component with original ROTEXspare parts.

7 x Gas burner


7.3.5 Setting ignition and Ionisation electrodes

The electrodes are configured at the factory.

After the replacement or for maintenance purposes, it may be necessary to check the electrode spacing and adjust where nec-essary (for dimensions, see fig. 7-4).

After the replacement or adjustment of the electrodes, the burner will need to be reset; the function and leak-tightness of the elec-trode flanges and the burner settings will need to be checked (see section 7.3.3).

7.4 Dismantling the burner

The burner works, as a rule, almost without any wear and residue. It may be necessary to dismantle the burner for some cleaning and servicing jobs or if there is damage in the com-bustion chamber area.

Burner dismantlingBlock gas supply.Disconnect ROTEX GCU compact from the power supply(fuse, main switch switched off) and secure against uninten-tional restart.Remove the sound insulation hood (see chapter 4.4.3).Remove the upper burner trim (see chapter 4.9.3).Remove the safety clamp (fig. 7-5, item 1) for the Venturinozzle.Disconnect the mains plug for the blower and the plug for theblower controller (fig. 7-5, item 2+3).Undo 4 fixing screws (fig. 7-5, item 4).Remove the burner blower with burner flange from the boilerbody.Remove the burner flange seal (fig. 7-5, item 5) andgenerally replace when installing.Remove the burner surface (fig. 7-5, item 6) from the boilerbody and check for damage, replace where necessary.

CAUTION!

Ignition electrodes can break with cold deformation.

Dismantle the burner before adjusting theelectrodes and make the electrodes glow by usinga solder lamp.

Fig. 7-4 Adjustment of the ignition and ionisation electrodes

WARNING!

Live parts can cause an electric shock on contact and cause fatal burns or injuries.

Before removing the burner, shut off the mainswitch for the heater and secure against uninten-tional restart.


An incorrect burner removal and installation can lead to gas leakages.

Generally replace seals.Observe the fitting positions.

WARNING!

Danger of burning on hot surfaces.

Let the burner cool down sufficiently beforedismantling.Wear protective gloves.


7 x Gas burnerBurner installation

Assemble the burner in reverse order to its removal.– The burner surface and boiler body are marked in colour

(arrows) and may only be assembled where they match.

– Pay attention to the stipulated tightening torque(see chapter 12.3).

Check the gas line for leakage.Start the burner. Check for function, leakage at the burnerflange and the settings (see section 7.3.3).

1 Safety clamp2 Mains plug, blower3 Plug, blower controller4 4x fixing screws (burner flange / boiler body) 5 Burner flange seal6 Burner surfaceFig. 7-5 Removing the burner

Fig. 7-6 Installing the burner - seat of burner surface on boiler body

8 x Hydraulic connection


8 Hydraulic connection

8.1 Hydraulic system connection

WARNING!

To prevent the emission of exhaust gas, before com-missioning the ROTEX GCU compact, the storage tank container must be filled up to the overflow mark.

WARNING!

High temperatures can occur in the solar storage tank. Therefore, sufficient scalding protection must be included when the hot water system is installed (auto-matic hot water mixing device).

CAUTION!

The ROTEX units can also be optionally fitted with gravity breaks ( 16 50 70) made of plastic. They are suitable for maximum operating temperatures of 95°C. If a heat exchanger is operated at temperaturesgreater than 95°C, another gravity brake must be installed in the building.

A selection of diagrams of the most common systems is shown below. The arrangements shown are only examples, and are no substitute for careful system planning. For more diagrams see the ROTEX home-page.

Short name Meaning1 Cold water distribution network2 Hot water distribution network3 Heating inflow4 Heating return flow5 Mixer circuit6 Circulation7 Check valve, return valve7a Non return valves8 Solar circuit

3UV DHW 3-way distribution valve (hot water/heater)3UVB1 3-way mixer valve (heater/internal boiler circuit)

D

FLS FlowSensor - solar flow and flow temperature measurement

H1,H2 ... Hm Heating circuitsMAG Diaphragm expansion vesselMIX 3-way-mixer with drive motorMK1 Mixer group with high-efficiency pump

MK2 Mixer group with high-efficiency pump (PWM controlled)

PK Boiler circuit pump

PMi Mixing circuit pumpPS Solar operating pump +

PZ Circulation pumpRoCon BF Control unit GCU compactRoCon M1 Mixer circuit control

Solar regulating and pump unit SK Solar panel fieldSV Safety overpressure valvetAU Outside temperature sensortDHW Storage tank temperature probetMi Mixer circuit flow temperature sensor

tV2 Internal mixer sensor boiler circuitTK Solaris collector temperature sensorTR Solaris return flow temperature sensorTS Solaris storage cylinder temp. sensorTV Solaris inflow temperature sensorVS Burns guard VTA32

Tab. 8-1 Short names in hydraulic drawings

Short name Meaning


8 x Hydraulic connection

Fig. 8-1 GCU compact 3xx with DrainBack solar (for legend, see tab. 8-1)

Fig. 8-2 GCU compact 5xx with DrainBack solar (for legend, see tab. 8-1)

9 x Service and maintenance


9 Service and maintenance

9.1 General overview of service and maintenance

Regular inspection and maintenance of the heating system re-duces energy consumption and ensures a long life and smooth operation.

Tests during annual inspection– General condition of the heating system, visual inspection of

connections and pipes.– Condensate drain– Check on the water pressure of the cold water supply

(<6 bar), install/set up the pressure regulator.– Burner operation and burner settings.

Maintenance work to be carried out annually– Cleaning the burner components, the combustion chamber

and the heating surfaces.– External cleaning of the storage tank and sound insulation

hood.– Replacement of the wearing parts if required).– Documentation of the maintenance work in the operating

manual.– Before recommissioning the ROTEX GCU compact after

maintenance work the conditions for commissioning as perchapter 5.2 must be checked and fulfilled.

9.2 Service and maintenance tasks

Cleaning silencer hood and storage tankThe low-maintenance plastic only needs to be cleaned with asoft cloth and a mild detergent.Do not use any cleaners with aggressive solvents (damage to the plastic surface may occur).

9.2.1 Checking the connections and pipes

Remove the sound insulation hood.

Inspect all (flue) gas and water carrying components andconnections for leakages and system integrity. If damaged,determine the cause and replace the damaged parts.Check all components of the flue system for leakage anddamage. Repair damaged parts or replace them.Check all electrical components, connections and pipes.Repair damaged parts.

9.2.2 Checking and cleaning the condensate drain.

The connection and leakage line of the condensate drain must be free from impurities.

If a solar system (DrainBack system) is connected and is inoperation, switch it off and empty the solar panels.Unscrew the overflow hose.Open the condensate drain (connection and drain conduit).Check that the condensate drain is free from blockages andclean if necessary.Visual inspection of container filling level (water level at theoverflow rim).If necessary, correct the fill level; determine the reason for the low water level and remedy it.

Have the inspection and maintenance carried out by authorised and trained heating engineers once a year and, if possible, before the heating period. This will avoid malfunctions during the heating period.

ROTEX recommends an inspection and maintenance contract to ensure regular inspection and maintenance.

WARNING!

Live parts can cause an electric shock on contact and cause fatal burns and injuries.

Before beginning the maintenance work,disconnect the ROTEX GCU compact from thepower supply (fuse, shut off main switch) andsecure against unintentional restart.

CAUTION!

Danger of burning - hot surfaces.

Let the burner cool down for a reasonably longtime before maintenance and service work.Wear protective gloves.

WARNING!

Improperly performed work on power or gas lines can endander life and health and hinder the operation of the ROTEX GCU compact.

Damage repair to live or gas carrying componentsof the ROTEX GCU compact must only beconducted by heating engineers that areauthorised and approved through the gas orenergy supply company.

UK only!

CAUTION!


Fig. -1 Unscrew/loosen screws, lift the cover at the back and remove in a forwards direction.


9 x Service and maintenanceCheck the overflow hose connection and drain section forleakage, unobstructed flow and gradient.

9.2.3 Checking and cleaning the burner

As a rule, the burner does not wear. If contaminations or unsatis-factory combustion values are detected, the burner must be re-moved (see chapter 7.4 "Dismantling the burner"), cleaned and, if necessary, re-adjusted (see chapter 7.3 "Burner setting").

Cleaning the combustion chamber

Remove the burner (see chapter 7.4 "Dismantling theburner")Rinsing the flue gas path with clean water (hose in the opencombustion chamber).

Checking the burnerChecking the burner includes visually inspecting the burner's condition as well as making flue gas measurements.

The scope of inspection includes:Clean the surface of the burner (blow off with compressed airor vacuum).Conduct a visual inspection of the ignition and ionisationelectrodes for damages and correct electrode gap (see chapter 7.3.5 "Setting ignition and Ionisation electrodes").

If necessary, replace faulty parts.Mount burner in combustion chamber.Check the gas line for leakage.Check combustion values:– Flue gas temperature at measuring sockets of the flue gas

pipe. (Target value < 80°C),– O2- or CO2-content (see chapter 7.3.1 "Setting values"),– CO content (target value < 50 ppm).

If the combustion values lie not within the target range, the burner must be adjusted according to chapter 7.3 "Burner setting".

Fig. 9-2 Check condensation water drain

The condensate is a weak acid. It is added to the de-pressurised zone of the hot water storage. Under normal plant operation, this ensures that the storage tank is always filled up to the overflow edge. A long-term neutralisation filling in the container ensures that the fluid leaving the container has neutral pH. Any dep-ositions remain in the pressureless area of the con-tainer.


Escaping gas is a direct threat to human health and safety. Even a few sparks can cause major explo-sions.

Only heating specialists authorised and trained bythe gas or power supply company should beallowed to work on gas-conducting parts.

WARNING!

Danger of burning - hot surfaces.

Let the burner cool down for a reasonably longtime before maintenance and service work.Wear protective gloves.

For exact information regarding the checking and set-ting of the burner, see chapter 7.3 "Burner setting".

For exact information regarding the assembly and dis-assembly of the burner, see chapter 7.4 "Dismantling the burner".

In the course of maintenance work, the safety relevant components must be additionally inspected for the expiration of their nominal service life:– Automatic firing unit: 10 years or 250,000 burner

starts,– Safety gas control block 10 years or 250,000 burner

starts,– Overpressure safety valve: 10 years.

We recommend, to enter all measured values and the conducted work with the date and signature into the enclosed operating handbook.

10 x Faults and malfunctions


10 Faults and malfunctions

10.1 TroubleshootingThe electronics of the ROTEX GCU compact– signals a fault by red backlighting in the display and– shows a fault code in the display.

An integrated fault memory stores up to 15 fault messages that have occurred most recently.

Depending on the operating mode, the fault messages are also forwarded to connected room stations or room thermostats.

TroubleshootingDetecting and remedying the cause of the malfunction.Non-interlocking malfunctions (see section 10.3) areindicated as long as there is a malfunction. Once the causehas been eliminated, the unit continues to work normally.Interlocking faults with fault code in the display (seesection 10.4).

By pushing the Exit button under the display for at least 5secs you can call up the "Special Level" and cancel theinterlock (menu-directed).

10.2 Overview of possible malfunctions

You will find detailed information on the control unit and the boiler control panel as well as on the operating modes and parameter settings in chapter 6 "Control unit" and in the documentation "ROTEX RoCon BF Controller" as supplied with the associated Control unit.

Malfunction Possible cause Possible solutionHeating system not functioning (main switch not illuminated, no display)

No mains voltage Switch on the main switch for the boiler.Turn on main switch of heating roomCheck / switch on fuse house connectionCheck/ renew fuse boiler control panelOnly use the same type of fuses!

Heating does not warm up

Central heating standby switched off (e.g. timer is in economy phase, outside temperature too high)

Check operating mode setting.1)

Check requirement parameter1) (e.g. timerprogramme)

Heating does not warm up enough

Heating characteristic too low Increase parameter value.1)

Carry out an hydraulic balancing.

Hot water does not warm up

Storage charging standby switched off (e. g. timer is in economy phase)

Check operating mode setting.1)

Check demand parameters.1)

Hot water does not warm up enough

Storage tank charging temperature too low Increase hot water set temperature.1)

Draw-off rate too high Reduce the draw-off rate, limit throughput.

Burner output too low See malfunction "Maximum burner output too low"

Maximum burner out-put too low

Burner setting wrong Check the burner settings and adjust as required(see chapter 7.3).Replace the safety gas control block.

Air/flue gas resistance too high Check the lines for contaminations.If necessary, install lines with a larger line cross-section for supply air or flue gas.

Burner does not start Interlocking malfunction Determine and repair the cause for the malfunction.Cancel interlock (see section 10.4).

Burner blocking contact closed Burner blocking contact was closed by an externalsource (e.g. solar system) - not a fault.



1) See documentation "ROTEX RoCon BF Controller"

Tab. 10-1 Possible faults on the GCU compact

Burner fan not run-ning despite burner demand

No mains voltage on burner Insert X1 plug on automatic firing until it clicks in place.Check voltage at the terminals L-N of the X1 plugCheck/ renew fuse.

Plug connections switching panel PCB or auto-matic firing are loose

Check/ insert plug connections

Burner blower defective (bearing has seized) Replace the burner blower.

No gas pressure Inspect the gas connections.

Air in the gas line Vent the gas line.

Gas control block does not open Check the plug connections between the safety gascontrol block and firing unit and insert correctly.Check the safety gas control block (zero pressureduring the ignition).Replace the safety gas control block.Replace the combustion controller.

No ignition See fault "No ignition".

Burner starting is hard Start delay due to bad ignition Adjust ignition electrodesCheck the starting output and adjust as necessary.

No ignition Ignition electrodes short circuited Check the ignition electrodes, adjust or replace asnecessary.

Distance of ignition electrodes too large Check the ignition electrodes and adjust wherenecessary.

ignition electrodes contaminated or humid Clean the ignition electrodes and check the burnersettings.

Ignition electrodes burnt out Change ignition electrodes

Insulating body cracked Change ignition electrodes

Ignition transformer defective Replace ignition transformer

Ignition cable defective, arking Change ignition cable and determine the cause

Firing unit faulty Replace the combustion controller.

Loud operating noises Wrong burner setting Re-adjust the burner setting.

Bearing damage on burner fan See fault "Loud, whistling mechanical noise".

Loud, whistling mechanical noise

Burner blower bearing defective Replace the burner blower.

STL switch off Water throughput too low due to air inclusion Vent system

Water flow too low due to valves closing too quickly along the entire heating network

Use slow closing or timed valves, if needed, installoverflow valve

Pump standstill Check mains and PWM control signal connection,replace pump if necessary.

Malfunction Possible cause Possible solution



10.3 Fault codes

Tab. 10-2 Error codes of interlocking malfunctions (can be detected by the firing unit)

Code Component/Designation FaultE12

Automatic firing unit

Interlocking fault

tV or tR defective (cable break, short circuit).

E65 During calibration, difference from prior value was too high (unclean supply air, electrode re-placement, electrode defective).

E129 Flow temperature exceeds limiter temperature (overtemperature, no heat dissipation)E130 Return flow temperature exceeds limiter temperature (overtemperature, no heat dissipation)E132 2x no flame formation at end of safety time (no gas, valves do not open, no ignition sparks)E138 2x flame failure at end of safety time (ionisation electrode defective or dirty)

E148 Gas valve test negative. A flame is still detected 15 s after the burner shutdown (gas valve jams).

E152 Speed not reached during pre- and post-ventilation (burner blower defective, power supply to blower, electronics fault in the blower, cable break).

E154 Blower stationary position not reached (burner blower defective, electronic fault in the burner blower).

E158 EEPROM fault (manufacturer’s parameters).E159 EEPROM fault (safety parameters).

E189Regulation deviation during ionisation process too high (as of 2nd fault) (burner grounded in-correctly or faulty supply voltage firing unit, gas flow pressure too low, ionisation electrode bent or oxidised, ionisation track faulty, safety gas control block defective)

E190

– Impermissible gas fitting initiation within 10 s (from the 2nd fault) or– Blower falls below 80 % of the minimum speed within 10 s (from the 2nd fault).

(Burner blower defective, wrong gas type set, missing/incorrect gas nozzle, safety gas con-trol block defective, gas flow pressure too low)

E191 Internal electrical fault- from the 2nd fault (switch the unit on/off).

E192 A value fell beneath the minimum thresholds during calibration (flue gas recirculation, elec-trodes oxidised, ionisation track faulty, poor earthing, transition resistances).

E194 Interruption during calibration (no heat dissipation, minimum calibration time not met).E195 Impermissible internal value (electronic fault).

E202 A value exceeded the maximum threshold values during calibration (unclean supply air, basis value too high).

E215 EEPROM fault (electronic fault).

E226 Fault found in the flame amplifier evaluation during the idle state check (electronic fault, shortcircuit ionisation electrode or cable).

E227 Internal fault to firing unit.



Tab. 10-3 Error codes temporary faults (can be detected by firing unit)

Code Component/Designation FaultE2


Temporary fault, burner shut-down, automatic release when error condition no longer active.

Return temperature exceeds the monitor temperature (overtemperature, no heat dissipation)E6 Flow temperature exceeds the monitor temperature (overtemperature, no heat dissipation)

E32 Undervoltage with 230 V mains voltage or 18 V internal DC voltage (electronic fault, switch unit on/off).

E43 Return temperature (tR1) is higher than the flow temperature (tV1) + 12 K for more than 5 s.E44 Flow temperature increase too rapid.E45 Spread (tV1 - tR1) too large.E66 Interruption during calibration (no heat dissipation, minimum calibration time not met).

E90Communication interrupted between the firing unit and the switching panel PCB of the control (check cable and plug connections, total reset, replace the switching panel PCB of the con-trol, replace the firing unit).

E96 5x Reset within 15 min. Another reset is not possible until a further 15 min.

E98 Fault found in the flame amplifier evaluation during the idle state check (electronic fault, short circuit ionisation electrode or cable).

E99 Internal fault to firing unit.E4


Temporary fault, unit is at-tempting to restart

1x no flame formation at end of safety time (no gas, valves do not open, no ignition sparks)E5 Flame failure in flame stabilisation (ionisation electrode defective or dirty).E10 Flame failure at end of the safety time (ionisation electrode defective or dirty).

E24 Value exceeds/falls below min. and max. limits during flame stabilisation or control operation (blower defective, power supply to blower, electronic fault in blower, cable break).

E50 Flame failure in regular operation (no gas, wind effect, safety gas control block supply).

E61Regulation deviation during ionisation process too high (1st fault) (burner grounded incor-rectly or faulty supply voltage firing unit, gas flow pressure too low, ionisation electrode bent or oxidised, ionisation track faulty, safety gas control block defective)

E62

– Impermissible gas fitting initialisation during 10 s (1st fault) or– blower falls below 80 % of the minimum speed within 10 s (one-off fault).

(Burner blower defective, wrong gas type set, missing/incorrect gas nozzle, safety gas con-trol block defective, gas flow pressure too low)

E63 Internal electronic fault - 1. fault (switch the unit on/off).E68 Impermissible GPV offset value (safety gas control block defective).

E69 No stable state in partial load reached during adaption within the tolerance period (wind effect, speed fluctuations, blower).



Tab. 10-4 Fault codes (can be detected by switching panel PCB)

10.4 Rectifying burner faults and STB faults

Interlocking faults detected by the automatic firing unit can only be reset manually directly on the boiler.

Unlocking the automatic firing unit: Requirements: The cause of the malfunction is rectified, the burner is electrically connected.

1. Switching ROTEX GCU compact on.

2. Push the Exit button (fig. 6-1, item 15) for at least 5 secs.Menu "Special Level" is displayed.

3. Select the "FA failure" level with the rotary switch.Fault code and request "Reset" is displayed.

4. Select "Yes" with the rotary switch.

5. Confirm the changes with a brief push of the rotary switch.Fault is reset.

6. Cancelling and jump back by pushing the Exit button again.

Code Component/Designation Fault Possible fault rectificationE72 Internal mixer sensor

Measured value outside measuring range, temperature sensor defective.

Check cable, terminal and plug connec-tions.Replace the temperature sensor.

E75 Outside temperature sensor

E76 Storage tank temperature sensor

E81 EepromInternal fault

Total resetReplace switching panel PCB incontroller.E88 Switching panel PCB control-

ler

E91 Connected CAN modules Bus detection of a CAN module doubly pre-sent.

Set bus addresses correctly.

E100 Flue gas temperature Internal fault Replace the combustion controller.

E129 Pressure sensor Measured value outside measuring range, sensor / temperature sensor defective.

Check cable, terminal and plug connec-tions.Replace the sensor / temperaturesensor.

E198 FlowSensor Volume flow too low. Check heating circulation pump / filter /heating network.

E200 Communication automatic firing

Fault in communication between automatic fir-ing and switching panel PCB on controller.

Check cable and plug connections.Total resetReplace control panel PCB on the GasCombi Unit compact.Replace the combustion controller.

W8001

FlowSensor

Volume flow fell below the minimum limit. Check the parameter settings (seeControl System Instructions).Check the pipes and valves forblockages.Check the built-in circulation pump.

E8002 Flow under minimum threshold (300 l/h)

W8003Flue gas temperature

The flue gas temperature has exceeded the threshold temperature.

Clean the boiler

E8004 The flue gas temperature has exceeded the permissible absolute maximum value.

E8005

Water pressure

Measured value under permissible minimum value.

Top up heating water.Leak test

W8006 Warning message: Maximum permissible pressure drop exceeded.

W8007 Warning message: Measured value over per-missible maximum value.

Check diaphragm expansion vessel.Drain heating water.

WARNING!

Risk of burns due to very hot boiler body with STB fault.

Do not touch any metallic parts on the boiler.Let the boiler cool down.Wear protective gloves.

The cause of the last fault is saved in the unit and can be reconstructed on restarting the unit, even after power failure.


10 x Faults and malfunctions10.5 Emergency operationIf the settings on the electronic control are incorrect, an emer-gency heating operation can be maintained. To do so, activate the special function "Manual Operation" on the control (see en-closed operating instructions "ROTEX RoCon BF control").

When the 3-way valves are intact, the ROTEX GCU compact will switch to heating operation. The necessary flow temperature can be adjusted with the rotary switch.

A pressure charge can be achieved in the special function "Manual Operation" as follows,

a) by setting up manual parallel operation (seesection 10.5.1). Requirements and procedures are identicalto those in chapter 4.11.4.

or

b) by removing the valve drive of the 3-way valve (fig. 4-28,item 5.1) from the valve;–– GCU compact 5xx(BIV): 3UV DHW (fig. 3-4).

Press the unlocking button (fig. 4-28, item 5.2) and rotatethe motor head of the valve drive 1/4 turn to the left(bayonet system).Room heating is not possible while the valve drive isremoved.

10.5.1 Parallel operationIf the 3-way valve drive is defective or disconnected from the power supply, a manual parallel operation of heating circuit and storage tank charging circuit can be set up temporarily. This is only possible when the 3-way valve concerned is in the position "AB-B" (hand lever faces away from the valve body). The pro-cedure is identical to the one in chapter 4.11.4.

GCU compact 3xx(BIV): 3UV DHW (fig. 3-1)

11 x Taking out of service


11 Taking out of service

11.1 Temporary shutdown

If no heat and no hot water supply is needed for a long time, the ROTEX GCU compact can be shut up temporarily. However, ROTEX recommends putting the system into standby mode (see the documentation concerning "ROTEX controller). The heating system is then protected from frost. The pumps and valve pro-tection functions are active.

If there is a danger of frost, and the gas and power supply cannot be guaranteed, then– the GCU compact must be emptied,– suitable antifreeze measures must be taken for the connected

heating system and hot water storage tank (e.g. draining).

Emptying storage tank containerSwitch off the main switch and secure against restarting.Close the gas isolation valve.Connect the hose and hose connection from the accessoriesset to the rear of the solar panel . When the ROTEX solarsystem is connected, use the KFE cock on the solar returnflow.

Drain out water content from container.

Emptying heating circuit and drinking water heat exchanger

Switch off the main switch and secure against restarting.Close the gas isolation valve.Disconnect the heating flow and return flow, as well as thecold water inflow and the hot water outflow.Connect drain hoses in hoses in such a way that the hoseopening is leakproof on the floor.Allow heat exchanger to run idle according to siphonprinciple.

11.2 Final shutdown and disposalFor final shutdown of the ROTEX GCU compact

decommissioned (see section 11.1),disconnect it from all electrical, gas and water connections,disposed off in a professional manner.

Recommendations for disposalThe ROTEX GCU compact has an environmentally friendly design. During the disposal process, the only waste created is that which can be used for material or thermal recycling. The ma-terials used that are suitable for material recycling can be sepa-rated according to single variety.

CAUTION!

A heating system which is shut down can freeze in the event of frost and may suffer damage.

Drain the heating system that is shut down if thereis danger of frost.If the heating system is not drained, the gas andpower supplies must be secured and the mainswitch must remain switched on.

If there is danger of frost in case of unsafe gas and power supply only for a few days, due to the excellent heat insulation, the emptying of the ROTEX GCU compact can be dispensed with if the storage temper-ature is observed regularly and does not drop below + 3°C.

However, there is no frost protection for the connected heat distribution system through this.

ROTEX has complied with the standards for environ-mentally-friendly disposal as a result of the environ-mentally-friendly design of the GCU compact. Proper disposal in compliance with the respective national reg-ulations of the country of use is the responsibility of the user/owner.


12 x Technical data12 Technical data

12.1 Basic data

12.1.1 GCU compact 3xx

Type (1)* GCU compact 315 / 315 BIV GCU compact 324 / 324 BIVParameter UnitTotal storage capacity Litres 300Empty weight (11)* kg 86Total filled weight kg 386Dimensions (L x B x H) cm 59.2 x 61,5 x 195Maximum permissible storage water temperature °C 85Stand-by heating power kWh/24h 1.7Drinking water heat exchanger (stainless steel)Water capacity heat exchanger Litres 19.0Heat exchanger surface area m2 4Max. operating pressure for the potable water PMW (14)* bar 6Storage tank charging heat exchanger (stainless steel)Water capacity heat exchanger Litres 9.4Heat exchanger surface area m2 1,9Pressurised solar heat exchanger (stainless steel)Water capacity heat exchanger Litres — / 4.2 — / 4.2Heat exchanger surface area m2 — / 0.8 — / 0.8Pipe connectionsCold and hot water Inch 1" AGHeating feed and return flow Inch 1" IGThermal performance data (sanitary)Efficiency characteristic NL according to DIN 47081) 2.0 2.1D-value (specific Water flow) according to EN 6252) (15)* l/min 22 24Continuous rating QD according to DIN 4708 kW 15 24Max. draw-off rate for a period of 10 min at (TKW = 10°C / TSP = 60°C / TWW = 40°C)

Litres 19 21

Hot water quantity without reheating up to 15 l/min tapping rate (T KW = 10°C / TWW = 40°C / TSP = 60°C)

Litres 200

Domestic hot water quantity with reheating at rated output and 15 l/min at tapping rate (TKW = 10°C / TWW = 40°C / TSP = 60°C)

Litres 300 400

Short time water quantity in 10 min3) Litres 190 210Electrical systemEnergy efficiency according to efficiency guidelines

Max. electric power consumption (without/with heating circulation pump)

(9)* W 90

Max. electric power consumption in operating mode "Standby"

W 3,4

Voltage supply (8)* ~230 V, 50 HzProtection type (10)* IP X0B1) Reheating with nominal output, flow temp. TV = 80°C, starting storage tank temp. TSP = 65°C, cold water temp. TKW = 10°C, domestic hot water temp. TWW = 45°C.2) The specific water flow according to EN 625 is the potable water flow with a mean temperature increase of 30 K, which the ROTEX GCU compact is able to deliver

in two consecutive tappings of 10 min duration each with a charging temperature of 65°C. A delay of 20 minutes between the two draw-off procedures is usuallyassumed. The ROTEX GCU compact reaches this value also with shorter waiting periods.

3) Reheating with nominal output, starting storage tank temp. TSP = 60°C, cold water temp. TKW = 10°C, domestic hot water temp. TWW = 40°C.

* Position numbers see fig. 12-1

Tab. 12-1 Technical data ROTEX GCU compact 3xx

12 x Technical data


12.1.2 GCU compact 5xx

Type (1)* GCU compact Parameter Unit 515 / 515 BIV 524 / 524 BIV 533 / 533 BIVTotal storage capacity Litres 500Empty weight (11)* kg 124Total filled weight kg 624Dimensions (L x B x H) cm 79 x 79 x 195Maximum permissible storage water temperature °C 85Stand-by heating power kWh/24h 1,8Drinking water heat exchanger (stainless steel)Water capacity heat exchanger Litres 24.5Heat exchanger surface area m2 5Max. operating pressure for the potable water PMW (14)* bar 6Storage tank charging heat exchanger (stainless steel)Water capacity heat exchanger Litres 10.5 19,3Heat exchanger surface area m2 2.1 4.0Pressurised solar heat exchanger (stainless steel)Water capacity heat exchanger Litres — / 12.7 — / 12.7 — / 12.7Heat exchanger surface area m2 — / 1.7 — / 1.7 — / 1.7Pipe connectionsCold and hot water Inch 1" AGHeating feed and return flow Inch 1" IGThermal performance data (sanitary)Efficiency characteristic NL according to DIN 47081) 2.1 2.2D-value (specific Water flow) according to EN 6252) (15)* l/min 23 25 27Continuous rating QD according to DIN 4708 kW 15 24 33Max. draw-off rate for a period of 10 min at (TKW = 10°C / TSP = 60°C / TWW = 40°C)

Litres 20 23 24

Hot water quantity without reheating up to 15 l/mintapping rate (T KW = 10°C / TWW = 40°C / TSP = 60°C)

Litres 230

Domestic hot water quantity with reheating at rated output and 15 l/min at tapping rate (TKW = 10°C / TWW = 40°C / TSP = 60°C)

Litres 370 600 1300

Short time water quantity in 10 min3) Litres 200 230 240Electrical systemEnergy efficiency according to efficiency guidelines

Max. electric power consumption (without/with heating circulation pump)

(9)* W 90

Max. electric power consumption in operating mode "Standby"

W 3,4

Voltage supply (8)* ~230 V, 50 HzProtection type (10)* IP X0B1) Reheating with nominal output, flow temp. TV = 80°C, starting storage tank temp. TSP = 65°C, cold water temp. TKW = 10°C, domestic hot

water temp. TWW = 45°C.2) The specific water flow according to EN 625 is the potable water flow with a mean temperature increase of 30 K, which the ROTEX GCU

compact is able to deliver in two consecutive tappings of 10 min duration each with a charging temperature of 65°C. A delay of 20 minutes between the two draw-off procedures is usually assumed. The ROTEX GCU compact reaches this value also with shorter waiting periods.

3) Reheating with nominal output, starting storage tank temp. TSP = 60°C, cold water temp. TKW = 10°C, domestic hot water temp. TWW = 40°C.

* Position numbers see fig. 12-1

Tab. 12-2 Technical data ROTEX GCU compact 5xx


12 x Technical data12.1.3 Integrated gas burner

12.1.4 Integrated heating circulation pump, 3-way valve

Type (1)* GCU compact (BIV)Parameter Unit 315 / 515 324 / 524 533Product ID (CE number) (3)* CE-0085 CO 0180Automatic firing unit Elster QCM434-R1Safety gas control block Elster CES10Burner fan Type 118Burner weight kg 2,8Nominal power Pn (6)* kW 6,5 - 15 6,5 - 24 6,5 - 33Rated thermal load Qn (5)* kW 6,5 - 15,7 6,5 - 25,3 6.5 - 32.5 (30.0)1)

Device type (2)* B23, B23P, B33, B33P, B53, B53P,C13, C33, C43, C53, C63, C83, C93

NOx class (to EN 15502-1) (4)* 5 (<60 mg/kWh)Water content boiler body Litres 1.5Max. permissible operating pressure PMS (12)* bar 3.0Max. permissible operating temperature (13)* °C 85Max. boiler efficiency % 110

Flue gas / air infeed connection diameter mm DN 60/100 (DN 80/125 with SET GCU1 ( 15 50 79.17))

1) Liquid gas setting* Position numbers see fig. 12-1

Tab. 12-3 Technical data, gas burner GCU compact

Parameter Unit Heating circulation pump Type Grundfos UPM2 15-70 CES87Voltage V ~230Frequency (power supply) Hz 50Maximum power consumption W 70Protection type IP 44Permitted overpressure bar 3Maximum pumping height m 7.0Energy efficiency EEI < 0.23

3-way valve: 3UV DHW / 3UVB1Type Honeywell VC4012 (SPST)Voltage V ~230Frequency (power supply) Hz 50Maximum power consumption W 4,3Protection type IP X0BTurnaround time S 6 150

Tab. 12-4 Technical data heating circulation pump, 3-way valves

12 x Technical data


12.2 Gas type, connection pressures

1 Type2 Unit type3 Product-ID (CE-Number)4 NOx-class5 Rated thermal load6 Nominal output7 Country of destination8 Voltage supply9 Electr. power input10 Degree of protection11 Net weight12 Max. permissible operating pressure (heater)13 Max. permissible operating temperature14 Max. operating pressure (sanitary)15 D value16 Serial number (indicate for complaints and inquir-

ies)17 Burner configuration18 Gas type19 Minimum burner load20 Max. burner load21 Gas type22 Minimum burner load23 Max. burner load

Fig. 12-1 Information on the Type plate (top) and settings type plate (bottom) — Information regarding the positions see tab. 12-1 to tab. 12-6

Gas type Rated pressure in mbar Min. inlet pressure in mbar Max. inlet pressure in mbarNatural gas E/H 20 17 25Natural gas LL/L 20 18 25

Liquid petroleum gas 50 42.5 57.5

Tab. 12-5 Permitted gas inlet pressure

Country of destination Appliance category Nominal connection pressure in mbar

Natural gas Liquefied petroleum gas

Natural gas Liquefied petroleum gas

DE II 2N3P 20/25 50DE II 2ELL3P 20 50AT, CH, CZ, SK II 2H3P 20 50CH, ES, FR, GB, IE, GR, IT, HR, PT, SI, LT, SK II 2H3P 20 37ES, FR, GR, PT, SI II 2N3P 20/25 37NL II 2L3P 25 37HU II 2H3P 25 30FR II 2E+3P 20/25 37FR II 2Er3P 20 37DK, FI, LV, NL, NO, SE, TR I 2H 20BE I 2E+ I 3P 20/25 37BE I 2N 20/25LU I 2E 20

Tab. 12-6 Countries of destination, unit categories and associated gas connection pressures (7)* * Position numbers see fig. 12-1


12 x Technical data12.3 Tightening torque

12.4 Flow rate and residual feed height 12.5 Temperature sensor

Component Comment Tightening torque in Nm

Fixing screws (top burner trim) fig. 4-31, item 1 3Fixing screw (burner flange / boiler body) fig. 7-1, item 13 6Safety screw (Venturi nozzle) fig. 7-1, item 2 3Fixing screw (ignition electrodes / ionisation electrode) fig. 7-1, item 18 3Fixing screw (burner blower / burner flange) fig. 7-1, item 12 6Fixing screw (burner blower / burner adapter) fig. 7-1, item 14 4Fixing screw (safety gas control block / gas connection line) fig. 7-2, item 15 2Temperature sensor and sensors all Max. 10Hydraulic line connections (Water) Thread 1" 25 - 30

Tab. 12-7 Tightening torque

ΔpR Remaining pumping heightmH Flow heating network

1 Modulation range

Fig. 12-2 Residual feed height GCU compact (heater side)

mH Flow heating network Q Heating outputFig. 12-3 Required throughput volumes dependent on the heating out-

put and the design temperature spread

0

100

200

300

400

500

600

700

800

0 500 1000 1500 2000 2500

m / L/hH

Δp

/ m

ba

rR

RS Sensor resistance T TemperatureFig. 12-4 Resistance characteristics of the temperature sensor

Measuredtemperature

in °C

Temperature sensorType Specification *NTCSensor resistance in Ohm according to standard or manufacturer's indications

-20 98660-10 562500 33210

10 2024020 1271030 819540 541650 366360 253070 178280 127890 932

100 690110 519120 395

* Key see tab. 8-1 Safety devices

Tab. 12-8 Resistance values of the temperature sensor

tV , tR , tAU, tDHW, tMi

12 x Technical data


12.6 Electrical connection diagram

J1 3-pin circuit board connector with pump ca-ble mains)

J2 4-pin circuit board connector with valve ca-ble

J3 6-pin circuit board connector (not occu-pied)

J5 3-pin circuit board connector with pressure sensor cable

J6 4-pin circuit board connector with clamped mains cable and earthing slots

J7 2-pin circuit board with PWM signal cable for external heating circulation pump

J8 12-pin circuit board connector to connect sensors and control lines

J9 5-pin circuit board connector (not occu-pied)

J10 3-pin circuit board connector with mains ca-ble for automatic firing CM434

J11 5-pin circuit board connector with mains ca-ble for automatic firing CM434

J12 4-pin circuit board connector:GCU compact 3xx: Not assignedGCU compact 5xx: Connection 3-way change valve (3UVB1)

J13 4-pin circuit board connector for connecting additional regulating system components (CAN-Bus)

J14 3-pin circuit board connector for clamping a circulation pump

J15 4-pin circuit board connector with switch cable

J16 4-pin circuit board connector for connecting a room thermostat (digital demand contact)

Mains supply 230 V, 50 Hz

Fig. 12-5 Wiring diagram ROTEX GCU compact


13 x Notes13 Notes

14 x List of keywords


14 List of keywordsNumerics

3 way mixer valveElectrical connection . . . . . . . . . . . 24

3-way switch valveElectrical connection . . . . . . . . . . . 24

3-way valveTechnical data . . . . . . . . . . . . . . . 58

AAdditional water . . . . . . . . . . . . . . 6, 31Annual inspection . . . . . . . . . . . . . . 47Annual maintenance tasks . . . . . . . 47Automatic firing unit . . . . . . . . . . . . . 39

BBoiler control panel . . . . . . . . . . . . . 34Burner

Dismantling . . . . . . . . . . . . . . . . . . 43Burner flange . . . . . . . . . . . . . . . . . . 44Burner malfunctions . . . . . . . . . . . . 53Burner output

Control . . . . . . . . . . . . . . . . . . . . . 39Burner setting . . . . . . . . . . . . . . . . . 39Burner setting values . . . . . . . . . . . 40

CCalibration . . . . . . . . . . . . . . . . . . . . 42Circulation pump (integrated)

Technical data . . . . . . . . . . . . . . . 58Combustion chamber

Cleaning . . . . . . . . . . . . . . . . . . . . 48combustion controller . . . . . . . . . . . 39Condensate drain

Connection . . . . . . . . . . . . . . . . . . 23Testing . . . . . . . . . . . . . . . . . . . . . 47

Condensing technologyInstructions . . . . . . . . . . . . . . . . . . 10

Connecting the mixer circuit . . . . . . 28Connection dimensions . . . . . . . . . . 11Connection kit

Accessories . . . . . . . . . . . . . . . . . 16Connection types - Flue gas . . . . . . 18Control

Connection . . . . . . . . . . . . . . . . . . 23Controls . . . . . . . . . . . . . . . . . . . . . . 34Convection brake . . . . . . . . . . . . . . . 9

DDanger of frost . . . . . . . . . . . . . . . . 55

Design and components . . . . . . . . . . 7Different set-ups

Ambient air-dependent mode . . . . 16Ambient air-independent mode . . . 15Overview . . . . . . . . . . . . . . . . . . . . 14

Dimensions . . . . . . . . . . . . . . . . . . . 11Disposal . . . . . . . . . . . . . . . . . . . . . 55Drinking water heating

Technical data . . . . . . . . . . . . 56, 57

EEfficiency . . . . . . . . . . . . . . . . . . . . . 10Electrical

Connection . . . . . . . . . . . . . . . . . . 23Electrical installation . . . . . . . . . . . . 23Electronic control . . . . . . . . . . . . . . . 10Emergency operation . . . . . . . . . . . 54

Emissions measurement . . . . . . . . . 64Exit button . . . . . . . . . . . . . . . . . . . . 34

FFault codes . . . . . . . . . . . . . . . . . . . 51Filling

Heating system . . . . . . . . . . . . . . . 28Outer layer of storage tank . . . . . . 28

Filling water . . . . . . . . . . . . . . . . . . . 31Firing unit . . . . . . . . . . . . . . . . . . . . . 53Flow rate . . . . . . . . . . . . . . . . . . . . . 60Flow temperature sensor . . . . . . . . . . 9FlowSensor . . . . . . . . . . . . . . . . .9, 35Flue gas mass flow . . . . . . . . . . . . . 19Flue system

Dimensioning . . . . . . . . . . . . . . . . 18Kits . . . . . . . . . . . . . . . . . . . . . . . . 20Minimum requirements . . . . . . . . . 18Piping height . . . . . . . . . . . . . . . . . 18

Flue system kits . . . . . . . . . . . . . . . . 20

GGas connection

Execution . . . . . . . . . . . . . . . . . . . 26Gas inlet pressure . . . . . . . . . . . . . . 26Gas type . . . . . . . . . . . . . . . . . .26, 27

Conversion . . . . . . . . . . . . . . . . . . 27

HHeating system

Draining . . . . . . . . . . . . . . . . . . . . . 55Hydraulic connection

Connection examples . . . . . . . . . . 45

IIgnition electrodes . . . . . . . . . . . . . . 43Inflow temperature sensor . . . . . . . . 36Installation area . . . . . . . . . . . . . . . . 16Installation room . . . . . . . . . . . . . . . 16Installation site . . . . . . . . . . . . . . . . . 16Internal mixer sensor . . . . . . . . . .9, 36Ionisation electrode . . . . . . . . . . . . . 43ISM . . . . . . . . . . . . . . . . . . . . . . . . . 10

MMains switch . . . . . . . . . . . . . . . . . . 34Maintenance . . . . . . . . . . . . . . . . . . 47Make-up water . . . . . . . . . . . . . . . . . 22Malfunctions . . . . . . . . . . . . . . . . . . 49Minimum distance . . . . . . . . . . .11, 16Mixer module . . . . . . . . . . . . . . . . . . 25

NNoise problems . . . . . . . . . . . . . . . . 42

OOperating mode . . . . . . . . . . . . . . . . . 9Operating safety . . . . . . . . . . . . . . . . 6Outer layer of storage tank . . . . . . . 45Output limits . . . . . . . . . . . . . . . . . . 41

PPower supply . . . . . . . . . . . . . . . . . . 23Pressure sensor . . . . . . . . . . . . . . . 36Proper use . . . . . . . . . . . . . . . . . . . . . 5

RRelevant documents . . . . . . . . . . . . . 5Residual feed height . . . . . . . . . . . . 60

Resting pressure . . . . . . . . . . . . . . .26Return flow temperature sensor .9, 36Room control . . . . . . . . . . . . . . . . . .28Room station . . . . . . . . . . . . . . . . . .28

SSafety gas control block . . . . . . . . .58Safety group . . . . . . . . . . . . . . . . . .16

Connection . . . . . . . . . . . . . . . . . .21Safety management . . . . . . . . . . . .10Safety shutdown . . . . . . . . . . . . . . .10Scope of delivery . . . . . . . . . . . . . . .16Service . . . . . . . . . . . . . . . . . . . . . .47Setting type plate . . . . . . . . . . . . . . .39Settings type plate . . . . . . . . . . . . . .59Shutdown . . . . . . . . . . . . . . . . . . . .55Solar utilisation . . . . . . . . . . . . . . . .10Sound insulation hood . . . . . . . . . . .18Starting output . . . . . . . . . . . . . . . . .42Starting problems . . . . . . . . . . .41, 42Start-up . . . . . . . . . . . . . . . . . . . . . .31

Checklist . . . . . . . . . . . . . . . . . . . .33Requirements . . . . . . . . . . . . . . . .31

Storage tank temperature sensor 9,25,37Surface temperature . . . . . . . . . . . .17Switch valve . . . . . . . . . . . . . . . . . .25

TTechnical data

GCU compact 3xx . . . . . . . . . . . . .56GCU compact 5xx . . . . . . . . . . . . .57

Temperature sensor . . . . . . . . . . . .25Tightening torque . . . . . . . . . . . . . .60Transport . . . . . . . . . . . . . . . . . . . . .16

UUnit installation room

Requirements . . . . . . . . . . . . . . . . .6

WWarranty . . . . . . . . . . . . . . . . . . . . . .4Water hardness . . . . . . . . . . . . . . . .22Water shortage protection . . . . . . . .22

15 x For the chimney sweep15 For the chimney sweep

15.1 Data for designing the flue gas pipe

Tab. 15-1 Triple values for chimney design (flue gas flow dependent on heat output, see fig. 4-12, page 19)

15.2 Emissions measurementThe check measurement can be made by a simply selectable automatic function (see also "Operating Instructions - ROTEX-RoCon BF Con-troller").

Depress the exit button for at least 5 secs.Menu "Special Level" is displayed.

Select the programme "Emission Measurement" with the rotaryswitch.Confirm the changes with a brief push of the rotary switch.

The following load types are available for selection:– Off: Emission measurement is switched off, any Gas Combi Unit

compact-connected heat generator that is switched on continues to be regulated normally.

– Base Load: The heat generator is switched on and operated atthe minimum output of the heat generator, irrespective of the set operating mode.

– Full Load: The heat generator is switched on and operated at the maximum output of the heat generator, irrespective of the set operating mode.

Select the load type "Full Load" using the rotary switch, but do notconfirm it.

Display: "Full Load"The burner is turned on for 30 min. and is regulated at maximum load.

Select the load type "Base Load" using the rotary switch, but do notconfirm it.

Display: "Base Load"The modulating gas burner runs at minimum output for 30 mins.

Cancellation and jump back by:– Pushing the exit button or rotary switch again– Selection of a different menu using the rotary switch and confir-

mation.

Unit Burner- load in kW

Rated output in kW Flue gas mass flow in g/s Flue gas temperature in °C Available delivery pressure in Pa40/30°C 80/60°C Natural

gas E/HNatural gas

LL/ LLiquefied petroleum

gas

40/30°C 80/60°C

GCU compact 315/515 (BIV)

6.5 6.8 6.4 3.06 2.38 2.73 32 63 4015.7 16.4 15.4 6.93 5.70 6.28 38 67 170

GCU compact 324/524 (BIV)

6.5 6.8 6.4 3,06 2.38 2.73 32 63 4025.3 25.8 24.0 11.31 8.78 9,94 43 71 200

GCU compact 533 (BIV)

1) Liquid gas setting

6.5 6.8 6.4 3.06 2.38 2.73 32 63 4030.01) 31.4 29.3 - - 12.59 44 73 20032.5 33.6 31.4 15.31 12.30 - 45 74 200

Fig. 15-1 Symbolic brief instructions for emission measurement

Emission Measurement

Off


Base Load


Full Load


Full Load

Special Level

Emission MeasurementManual Operation

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rotex installation and maintenance instructions

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