after sales service guide - de...

After Sales Service Guide

ZENA MS wall-hung gas boilers

300029718-001-A 28/09/2012

Use of this guide is reserved for qualified professionals

Symbols used

Any intervention on the appliance and heating equipmentmust be carried out by a qualified engineer.

Abide by prevailing local regulations.

For Belgium: Any work on the gas block must be carried outby a factory technician.

Caution danger Risk of injury and damage to equipment. Attention must be paid to the warnings on safety of persons and equipment

Specific information Information must be kept in mind to maintain comfort

Reference Reference to other paragraphs in the guide

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1. PRESENTATION - SPECIFICATIONSContents: page 6

2. OPERATING PRINCIPLEContents: page 16

3. PRODUCT EVOLUTIONContents: page 32

4. TROUBLESHOOTING DIAGRAMSContents: page 38

5. INSTALLATION - COMMISSIONINGContents: page 54

6. CONTROLS AND SETTINGSContents: page 76

7. ELECTRICAL DIAGRAMSContents: page 112

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1

PRESENTATIONSPECIFICATIONS

5

1

CONTENTS

1. Presentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71.1 The various models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71.2 Performance (in accordance with RT 2005 for France) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.3 Strong points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91.4 Control panel options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101.5 Boiler options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

2. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.1 Technical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.2 Characteristics of domestic hot water production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122.3 Location of the data plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132.4 Characteristics of the heating pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

6

1

1. Presentation

1.1 The various modelsBoiler Type of

connection Model Useful output range (kW)

Heating only

Chimney MS 24 9.3 - 24

Flue gas outlet* MS 24 FF 9.3 - 24

Heating and micro-storage domestic hot water production

ChimneyCMV (1)

MS 24 MIMS 24 MI VMC(1)

9.3 - 249.3 - 24

Flue gas outlet* MS 24 MI FF 9.3 - 24

Heating + DHWBoiler with integrated DHW tank (40 litres)

Chimney MS 24 BIC 10.4 - 23.3

Flue gas outlet* MS 24 BIC FF 10.4 - 24

* Horizontal forced flue: Diameter 60/100 mm orVertical forced flue: Diameter 80/125 mm + adapter

(1) for France only

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1
* Horizontal forced flue: Diameter 60/100 mm or
Vertical forced flue: Diameter 80/125 mm + adapter

Heating + DHW BS80 calorifierThe DHW calorifier can be placed to the left or right of the boiler.

Chimney MS 24 / BS80(MS 24 + BMR 80) 9.3 - 24

Flue gas outlet* MS 24 FF/ BS80(MS 24 FF+ BMR 80) 9.3 - 24

Heating + DHW BS130 calorifierDHW tank placed under the boiler.

Chimney MS 24 / BS 130(MS 24 + SR 130) 9.3 - 24

Flue gas outlet* MS 24 FF / BS 130(MS 24 FF+ SR 130) 9.3 - 24

Boiler Type of connection Model Useful output range (kW)

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1

1.2 Performance (in accordance with RT 2005 for France)

1.3 Strong points• Compact, user-friendly boiler thanks to its accessibility and the easy dismantling of all its components: all components can be

accessed from the front.• Combustion chamber:

- Primary exchanger (heating body) in copper pipes with fins, coated with aluminium silicone paint, enhancing its resistanceto heat.

- Atmospheric gas burner with stainless steel burner trains.• Electronic ignition and flame control by ionization,• Modulating gas valve with dual safety solenoid valve,• Control panel:

- Electronic control panel with easy to use, direct access digital display, - Display of the error code on the digital display console to facilitate troubleshooting,- The control panel is used as standard to manage a direct circuit and a DHW circuit,- Optional regulation of the heating circuit by adding a programmable or non-programmable room temperature thermostat

(wire- or radio-controlled) and/or an outside temperature sensor,- Anti-blocking function for the pump and the reversal valve.

• Compact water unit (Hydroblock):- In brass for the MS 24, MS 24 FF versions- In composite material for the MS 24 MI, MS 24 MI FF, MS 24 VMC, MS 24 BIC and MS 24 BIC FF versions- 2-speed heating pump with automatic air vent- Automatic bypass- Motorised heating / DHW reversal valve fitted to the return- Low water pressure switch- Boiler and disconnector drain valve- Heating circuit safety valve (3 bar) - Safety valve on the DHW circuit (7 bar - For MS 24 BIC and MS 24 BIC FF boilers)- Pressure gauge- The filters on the heating and DHW circuits are housed in detachable cartridges- Stainless steel plate exchanger for DHW production (MI and BIC versions)- Turbine flow switch for measuring the DHW flow rate (MI and BIC versions)

• 6-litre expansion vessel (Heating circuit) - all versions excepted BIC• BIC Versions: 7,5-litre expansion vessel (Heating circuit)• Extraction fan and air pressure switch (FF Versions)• Downdraught thermostat (Chimney versions, Version VMC*)• Full antifreeze protection (heating and DHW circuits)• High energy efficiency:

- *** efficiency class for the FF versions- ** efficiency class for the chimney and VMC versions- N0x 3 class in accordance with pr EN297 A3 for the chimney versions, in accordance with EN483 for the FF versions.

• The IPX5D protection rating allows the boiler to be installed in a kitchen or bathroom.

* Version VMC: for France only.

Generator type:- MS 24 (FF): Heating only- MS 24 MI (FF, VMC): Heating and domestic hot water. Boiler with

< 10 litres of additional storage integrated in the secondary circuit.- MS 24 BIC (FF) : Heating and domestic hot water (Boiler with

integrated DHW tank > 10 litres)Boiler type: Low temperature atmospheric gas boilerBurner: Atmospheric with no fan (Chimney versions); Atmospheric with fan (FF Versions).

Energy used: Natural gas (All models) or Propane (except MS 24 MI VMC)Combustion evacuation: Chimney, Flue gas outlet or CMV.Min. return temperature: 20 °CMin flow temperature: 30 °CEC certificate reference:

MS... : 51BT3644/45DR/ED03MS... FF : 51BT3642/43DR/ED03MS... VMC : 51CL4020/21DR/ED03.

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1.4 Control panel optionsAD137 / AD200 / AD247 / AD248

AD269

AD140

Programmable, wire-controlled room thermostat - Package AD137 / AD247Wireless settable ambient thermostat - Package AD200 / AD248Programmable, wire-controlled room thermostat 230 V - Package AD269Non settable ambient thermostat - Package AD140.

Domestic hot water sensor - Package AD250The DHW sensor is used for the priority control of the temperature and theprogramming of domestic hot water production by an accumulation tank.

Outside sensor - Package HX31The outside temperature sensor can be used on its own or in combination with theroom thermostats to regulate the heating according to the outside temperature.

8801

Q029

MCX_

Q000

988

01Q0

03de

tMS

_Q00

05

10

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1.5 Boiler options

For the other hydraulic connection options, refer to the current product catalogue.

Stove fittings accessories, specific to MS boilers

DHW expansion vessel (For MS 24 BIC - MS 24 BIC FF)- Package HX26Capacity : 2 litres.Used to prevent water loss caused by expansion when reheating the DHW tank.

DHW calorifiers:- BMR80: Package EE53. Wall-hung DHW tank - 80 litres- Connection kit BMR80 / MS24 : Package HX33.- SR130: Package EE22. Floor-standing DHW tank - 130 litres - DHW sensor included.- Connection kit SR130 / MS24 : Package HX32.

Hyrdaulic connection kit for a solar circuit with directional thermostatic valve - Package HX23 (For MI versions only)This kit contains all the pipes needed to connect the boiler to a solar DHW tank, including the directional thermostatic valve and the cold water isolating valve. It makes it possible to combine a solar system with a boiler with micro-storage domestic hot water production, thus handling regulation of the solar DHW system according to the needs of the user.

Filling kit with pressure gauge - Package HX27.To be connected between the heating flow valve at one end and the domestic cold water inlet on the boiler's hydraulic connection plate at the other.

Propane conversion kitfor: MS 24, MS 24 FF, MS 24 MI, MS 24 MI FF - Package HX28- for: MS 24 BIC, MS 24 BIC FF - Package HX29

Horizontal terminal Alu Diameter 60/100 mm - Package DY908Horizontal terminal Alu Diameter 80/125 mm, Length 730 mm - Package CX119Vertical terminal Alu Diameter 80/125 mm - Package DY735 (Black) or DY736 (Red)Condensates adapter/recuperator - From diameter 60/100 to 80/125 mm (Alu) - Package DY909Condensate collector - Diameter 60/100 mm (Alu) - Package DY910

Bi-flow boiler connection kit - Package HX30

3 CE pipe connection kit Diameter 60/100 mm - Package DY911

MS_Q

0030

BMR80 SR 130

MCR_

QG00

10

8666

QG04

3AMS

_Q00

06MS

_Q00

29MS

_Q00

04G0

0025

8

G000

256

DY908 DY736

DY909 DY910

G000

255

G000

259

G000

257

DY911

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2. Specifications2.1 Technical specifications

(1) for France only - (2) For VMC versions: No operation on propane.

2.2 Characteristics of domestic hot water productionConditions of validity of the table: Ambient temperature 20 °C, Cold water temperature 10 °C, Primary hot water temperature85°C.

(1) for France only

Boilers MS 24 24/BS...

24 FF24 FF/BS...

24 MI24 MI VMC(1) 24 MI FF 24 BIC 24 BIC FF

Generator typeMS 24 (FF): Heating only

MS 24 (FF)/BS:Heating and DHW with separate domestic

hot water tank

Heating and domestic hot water: Boiler with 10 litres of additional storage integrated

in the secondary circuit

Heating and integrated domestic hot water tank

Nominal useful output Pn (heating and DHW modes) kW 24 24 24 24 23.3 24

LHV efficiencyat 100% Pn - 70 °Cat 30% Pn - 40 °C

%%

91.290.2

92.990.4

91.290.2

92.990.4

91.089.8

92.990.6

Nominal water flow rate at Pn, ∆T = 20 K m3/h 1.03 1.03 1.03 1.03 1.00 1.03Stand-by losses to ∆T = 30 K W 183 59 183 59 199 99Minimum useful output (heating and DHW modes) kW 9.3 9.3 9.3 9.3 10.4 10.4Manometric height available for the heating circuit mbar 175 175 175 175 230 220Water content l 3 3 3.5 3.5 5 5Gas flow rate at Pn

- Natural gas H or L- Propane

m3/hKg/h

2.78/3.232.04

2.73/3.172.00

2.78/3.232.04(2)

2.73/3.172.00

2.73/3.172.00

2.73/3.172.00

Required depressurisation at the nozzle mbar 0.5 - 0.5 - 0.5 -Mass flue gas flow rate at Pn Kg/h 0.014 0.020 0.014 0.020 0.021 0.017Electrical specificationsPower supply voltage V AC 230 230 230 230 230 230Auxiliary electrical power (Ex circulating pump) at Pn W 5 55 5 55 5 60

Electrical power circulating pump at Pn / Pmin W 75 / 75 75 / 75 75 / 75 75 / 75 75 / 75 75 / 75Electrical protection index IPX5D IPX5D IPX5D IPX5D IPX5D IPX5DOther characteristicsWeight (empty) kg 28 32 29 33 51 61

Boilers MS24 MI

24 MI FF24 MI VMC(1)

24 BIC 24 BIC FF 24 / BS8024 FF / BS80

24 / BS13024 FF / BS130

Tank capacity (Domestic hot water) l - 40 40 80 130

Power exchanged kW 24 23.3 24 24 24

Flow in 10 min. at ∆T =30 K l/10 mm - 180 180 210 260

Flow per hour at ∆T =35 K l/h 590 573 590 590 590

Specific flow at ∆T=30 K (in accordance with EN 13203-1) l/min 12.0 17.7 17.7 21.0 26.0

Auxiliary electrical power (In DHW mode) W 80 80 80 80 80

Losses through the outer casing at ∆T = 45 K W - 69 69 62 73

Cooling constant Cr Wh/24h·L·K - 0.67 0.67 - 0.27

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2.3 Location of the data plate

The data plate provides important information on the boiler: serial number, model, gas category, etc...

2.4 Characteristics of the heating pumpsThe following graphs show the manometric height at various outputs.If flow noises can be heard in the heating circuit, reduce the speed of the pump. First of all, vent the heating system. If the circulation in the radiators is too low or the radiators do not heat up completely, increase the speed of the pump (Bleed theradiators).

Pump GRUNDFOS UPSO 15-50 (2-speed pump)

H: Manometric height available with the pump, at ∆T=20 K.

Q: Water flow l/h

MS 24 BIC (FF) MS 24 (FF) - MS 24 MI ... (FF)

MS 24 MI - MS 24 MI FF - MS 24 MI VMC

MS 24 - MS 24 FF - MS 24 BIC - MS 24 BIC FF

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OPERATING PRINCIPLE

G000271

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CONTENTS

1. Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171.1 Control panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171.2 Main parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2. Operating principle diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222.1 Boiler MS 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222.2 Boiler MS 24 MI - MS 24 MI VMC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232.3 Boiler MS 24 FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242.4 Boiler MS 24 MI FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252.5 Boiler MS 24 BIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262.6 Boiler MS 24 BIC FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272.7 Description of the boiler operating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

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1. Description1.1 Control panel

Info mode

Alternating display:

Description of the keys: Press button for 5 seconds: The Info mode is active.The display shows the code A..., alternating with the value ofthe parameter.

Press the (+/-) keys on side to get an instant displayof the following information:

This function is active for 3 minutes.

To interrupt the "INFO" function in advance, press the button again. The display shows ESC.

Operating mode selection key :- Stop (Display: OFF) / Antifreeze protection active- DHW heating only: Only domestic hot water production

is ensured, the heating is switched off.(Display: Boiler temperature + )

- Heating only(Display:Boiler temperature + )

- Heating and domestic hot water(Display: Boiler temperature + + )

Reinitialisation (RESET)Press the Reset button for 2 seconds Info mode: Parameter display:

Info mode (see opposite) A00 Domestic hot water temperature (°C) If there is no DHW preparation, the display shows 99.

/ : Heating temperature setting A01 Outside temperature (if the optional outside temperature sensor is connected). If the sensor is not connected, a full stop is displayed. / : Setting the domestic hot water temperature

Display: A02 Current modulation value ( 100% = 230 mA on natural gas G20/G25 - 100% = 310 mA on propane G31).

Operating in heating mode A03 Percentage of maximum boiler output (%) in heating mode.Operating in DHW mode

Flame present A04 Heating temperature setting (°C)If an outside temperature sensor is connected, display of the heating gradient (Kt:See section 6, chapter 6.2).Igniter fault

ERRORReinitialisation A05 Current boiler temperature (°C)

No water / Pressure lower than 0.5 bar A06 Domestic hot water set point temperature (°C)Display,Depending on the situation:- Measured temperature- Set temperature- Operating modes- Failure code

A07 Not used.

A08 Domestic hot water flow (l/min x 10) - For versions MI and BIC only

A09 Last error which occured.

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1.2 Main partsMS 24

MS 24 FF

1 Control panel (in tilted position)2 Low water pressure switch3 Gas valve (with diaphragm)4 Gas pressure measurement point5 Ignition/ionization electrode

6 Atmospheric gas burner with stainless steel burner trains

7 Boiler temperature sensor8 105 °C safety thermostat9 Air pressure switch (FF versions only)

10 MS 24 FF : Air/flue gas connection Ø 60/100 mm MS 24 : Flue gas nozzle Ø 125 mm

11 Venturi (FF versions only)12 Extractor fan (FF versions only)13 Combustion chamber14 Primary exchanger (Water / flue gases)15 Flame inspection window16 Expansion vessel 6 litres17 2-speed heating pump with automatic air vent

18 Heating / DHW inversion valve

19 Disconnector

20 Filling valve

21 Pressure gauge

22 Heating circuit safety valve

Model shown: MS 24 FF

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2

MS 24 MI FF

1 Control panel (in tilted position)2 Low water pressure switch3 Gas valve (with diaphragm)4 Gas pressure measurement point5 Ignition/ionization electrode


7 Boiler temperature sensor8 105 °C safety thermostat9 Air pressure switch10 Air/flue gas connection Ø 60/100 mm 11 Venturi12 Extractor fan13 Combustion chamber14 Primary exchanger15 Flame inspection window16 Expansion vessel 6 litres17 Stainless steel plate exchanger for the production of

micro-storage DHW18 2-speed heating pump with automatic air vent

19 Heating / DHW inversion valve

20 Disconnector

21 Filling valve (Blue)

22 Pressure gauge


24 Domestic hot water outlet temperature sensor

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2

MS 24 MI MS 24 MI VMC

1 Control panel (in tilted position)2 Low water pressure switch3 Gas valve (with diaphragm)4 Gas pressure measurement point5 Ignition/ionization electrode6 Atmospheric gas burner with stainless steel burner trains7 Boiler temperature sensor8 105 °C safety thermostat9 Draught diverter10 Flue gas nozzle Ø 125 mm11 Combustion chamber12 Primary exchanger13 Expansion vessel 6 litres14 Stainless steel plate exchanger for the production of micro-

storage DHW15 2-speed heating pump with automatic air vent16 Heating / DHW inversion valve17 Disconnector

18 Filling valve (Blue)

19 Pressure gauge


21 Domestic hot water outlet temperature sensor

Model shown: MS 24 MI

20

2

MS 24 BIC FFMS 24 BIC

1 Control panel (in tilted position) 14 Flame inspection window2 Pressure gauge 15 Primary exchanger (Water / flue gases)3 Heating / DHW inversion valve 16 Stainless steel plate exchanger for DHW production4 Gas valve (with diaphragm) 17 DHW tank5 2-speed heating pump with automatic air vent 18 Tank temperature sensor6 Disconnector 19 Safety valve on the DHW circuit7 Atmospheric gas burner with stainless steel burner trains 20 DHW load pump8 Air pressure switch (FF versions only) 21 Flow switch (domestic water)9 Venturi (FF versions only) 22 Expansion vessel 7.5 litres (Heating circuit)

10 Extractor fan (FF versions only) 23 Boiler temperature sensor11 105 °C safety thermostat 24 Heating circuit safety valve12 Ignition/ionization electrode 25 Low water pressure switch13 Combustion chamber

Model shown: MS 24 BIC FF

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2

2. Operating principle diagram

2.1 Boiler MS 24

1 Automatic bypass2 Low water pressure switch3 Heating / DHW inversion valve4 Reversal valve motor5 Gas valve (with diaphragm)6 Gas ramp (with injection nozzles)7 Boiler temperature sensor8 Ignition/ionization electrode9 105 °C safety thermostat10 Primary exchanger (Water / flue gases)11 Draught diverter cut-off12 Flue gas thermostat - 70 °C13 Atmospheric gas burner with stainless steel burner

trains14 Expansion vessel 6 litres15 2-speed heating pump with automatic air vent16 Non-return valve17 Drain cock (Boiler)

18 Pressure gauge


20 Disconnector

Heating flow

Primary flow to DHW tank

Gas inlet

Domestic cold water inlet (Filling valve)

Heating return

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2

2.2 Boiler MS 24 MI - MS 24 MI VMC

1 2-speed heating pump with automatic air vent2 Non-return valve3 Heating / DHW inversion valve 4 Reversal valve motor5 Pressure gauge 6 Filter (Heating circuit)7 Disconnector8 Filling valve (boiler)9 Filter (Domestic cold water inlet)10 Flow switch (domestic water)11 Domestic hot water outlet temperature sensor12 Non-return valve (on automatic bypass)13 Low water pressure switch 14 Drain cock (boiler)15 Heating circuit safety valve16 Plate heat exchanger (Water / Water)17 Gas valve (with diaphragm)

18 Gas ramp (with injection nozzles)

19 Heating flow temperature sensor

20 Ignition/ionization electrode

21 105 °C safety thermostat

22 Primary exchanger (Water / flue gases)

23 Draught diverter cut-off

24 Flue gas thermostat MS 24 MI : 70 °CMS 24 MI VMC : 57 °C


26 Expansion vessel 6 litres

Heating flow

Domestic hot water outlet

Gas inlet


Heating return

23

2

2.3 Boiler MS 24 FF

1 Automatic bypass2 Low water pressure switch3 Heating / DHW inversion valve 4 Reversal valve motor5 Gas valve (with diaphragm)6 Gas ramp (with injection nozzles)7 Heating flow temperature sensor8 Ignition/ionization electrode9 105 °C safety thermostat10 Primary exchanger (Water / flue gases)11 Flue gas header 12 Extractor fan 13 Venturi14 Positive pressure outlet15 Negative pressure outlet16 Air pressure switch


18 Expansion vessel 6 litres19 2-speed heating pump with automatic air vent20 Non-return valve21 Drain cock (Boiler)22 Pressure gauge


24 Disconnector

Heating flow

Primary flow to DHW tank

Gas inlet


Heating return

24

2

2.4 Boiler MS 24 MI FF

1 2-speed heating pump with automatic air vent2 Non-return valve3 Heating / DHW inversion valve4 Reversal valve motor5 Pressure gauge 6 Filter (Heating circuit)7 Disconnector8 Filling valve (boiler)9 Filter (Domestic cold water inlet)10 Flow switch (domestic water)11 Domestic hot water outlet temperature sensor12 Non-return valve (on automatic bypass)13 Low water pressure switch 14 Drain cock (boiler)15 Heating circuit safety valve16 Plate heat exchanger (Water / Water)17 Gas valve (with diaphragm) 18 Gas ramp (with injection nozzles)19 Heating flow temperature sensor20 Ignition/ionization electrode21 105 °C safety thermostat22 Primary exchanger (Water / flue gases)23 Flue gas header24 Extractor fan 25 Venturi26 Positive pressure outlet27 Negative pressure outlet28 Air pressure switch


30 Expansion vessel 6 litres

Heating flow

Domestic hot water outlet

Gas inlet


Heating return

25

2

2.5 Boiler MS 24 BIC

1 Filter (Heating circuit) 19 Tank temperature sensor2 Pressure gauge 20 Anode3 Heating / DHW inversion valve 21 DHW load pump4 Gas valve (with diaphragm) 22 Flow switch (domestic water)5 2-speed heating pump with automatic air vent 23 Drain cock (DHW tank)6 Non-return valve 24 Safety valve on the DHW circuit7 Disconnector 25 Expansion vessel DHW circuit (Option)8 Filling valve (boiler) 26 Heating circuit safety valve9 Gas ramp (with injection nozzles) 27 Drain cock (boiler)

10 Draught diverter cut-off 28 Low water pressure switch11 Flue gas thermostat 29 Non-return valve (on automatic bypass)12 105 °C safety thermostat 30 Plate heat exchanger (Water / Water)13 Primary exchanger (Water / flue gases)14 Ignition/ionization electrode Heating flow

15 Atmospheric gas burner with stainless steel burner trains Domestic hot water outlet

16 Heating flow temperature sensor Gas inlet

17 DHW tank (Stainless steel) Domestic cold water inlet (Filling valve)

18 Expansion vessel 7.5 litres (Heating circuit) Heating return

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2.6 Boiler MS 24 BIC FF

1 Filter (Heating circuit) 21 DHW tank (Stainless steel)2 Pressure gauge 22 Expansion vessel 7.5 litres (Heating circuit)3 Heating / DHW inversion valve 23 Tank temperature sensor4 Gas valve (with diaphragm) 24 Anode5 2-speed heating pump with automatic air vent 25 DHW load pump6 Non-return valve 26 Flow switch (domestic water)7 Disconnector 27 Drain cock (DHW tank) 8 Filling valve (boiler) 28 Safety valve on the DHW circuit9 Gas ramp (with injection nozzles) 29 Expansion vessel DHW circuit (Option)

10 Flue gas header 30 Heating circuit safety valve11 Air pressure switch 31 Drain cock (boiler)12 Negative pressure outlet (Not used) 32 Low water pressure switch13 Positive pressure outlet 33 Non-return valve (on automatic bypass)14 Venturi 34 Plate heat exchanger (Water / Water)15 Extractor fan Heating flow16 105 °C safety thermostat Domestic hot water outlet

17 Primary exchanger (Water / flue gases) Gas inlet

18 Ignition/ionization electrode Domestic cold water inlet (Filling valve)19 Atmospheric gas burner with stainless steel burner trains Heating return20 Heating flow temperature sensor

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2.7 Description of the boiler operatingDescription of the ignition phase

- The regulator controls the opening of the gas valve: themodulator opens the valve at 50 mA (G20/G25) or 70 mA (G31)

- The regulator simultaneously controls the appearance of sparkson the ignition electrode.

- During the safety time, the modulating valve opens with agradient of 36 mA/s (G20/G25) or 48 mA/s (G31). Safety time: 5 seconds.

- If a flame is detected after 3 seconds, the regulator continues tosupply current to the modulator until the maximum value of 230mA (G20/G25) or 310 mA (G31), with a gradient of 112 mA/s.

- The regulator then moves on to the next operation:- heating function (if no DHW requirement). The regulator

releases modulation after 20 seconds (between 50 and 230mA (G20/G25) or 70 and 310 mA (G31), in accordance withthe heating set point.

- full load DHW function (230 mA on G20/G25 or 310 mA onG31) then flame modulation phase in accordance with theDHW set point.

- If no flame is detected, the boiler switches to safety shutdown after 3 re-ignition attempts and displays the error code E01.Description of the operating modes

The key is used to select one of the following operating modes:OFF Stop / Antifreeze protection: (Display: OFF).

Antifreeze protection only is activated, no other requests are taken into account. DHW heating only: Only domestic hot water production is ensured, the heating is switched off. The antifreeze protection function is activated.(Display: Heating flow temperature + )

If the CTN sensor on the DHW circuit breaks down, hot water production continues nevertheless. The temperature will be controlled bythe heating sensor.

Heating only: heating is handled (The antifreeze protection function is activated). (Display: Heating flow temperature + )

+ Heating and domestic hot water: the boiler provides domestic hot water and the heating is on. (The antifreeze protection function is activated)(Display: Heating flow temperature + + )

Antifreeze protection (Heating circuit and Domestic hot water circuit)The boiler's electronic controller has an antifreeze protection function which trips the burner to reach a boiler temperature close to30°C when the boiler temperature is lower than 5°C.The antifreeze protection function is activated if:

- The boiler is electrically powered up,- The gas supply is available,- The pressure switch measures a pressure in the circuit higher than or equal to 0.5 bar,- The boiler is not in safety lockout.

Post-circulation of the heating pump (In heating mode): When the boiler is no longer required (e.g. room thermostat), post-circulation of the pump runs for 180 seconds. Post-circulation of the heating pump (In DHW mode):

When there is no DHW request, post-circulation of the pump runs for 30 seconds.For BIC versions: When there is no DHW request, post-circulation of both pumps runs for 30 seconds.

Pump anti-block function (unclogging)In heating mode, if there is no heating request, the pump runs automatically for 10 seconds every 24 hours. This function is onlyavailable if the boiler is electrically powered up.

Reversal valve anti-block functionIf there is no heating request, the reversal valve runs a full automatic cycle every 24 hours. This function is only available if theboiler is electrically powered up.

A: Ignition flowB: Flame detectionC: Switching to DHW or heating mode

28

2

Safety devices:- Air pressure switch (FF Versions): This device prevents burner operation when the flue gas circuit is blocked or presents

an anomaly (flue gas extraction terminal blocked, venturi blocked, fan blocked, venturi-pressure switch connectioninterrupted). In this case, the boiler shuts down and displays the error code E03.

- Flue gas thermostat (all versions excepted FF): This device, for which the sensor is located in the left-hand section of thedraught diverter, interrupts gas input to the main burner when the chimney is blocked or if there is no draught. In this case,the boiler shuts down and displays the error code E03.

- Safety thermostat: This device, for which the sensor is fitted to the heating flow, interrupts the gas supply to the burner inthe event of the water overheating in the primary circuit. In this case, the boiler shuts down and displays the error code E02.

- Ignition and flame detection electrode: fitted close to the burner, the ignition / ionisation electrode guarantees safety ifthere is no gas to the burner or ignition is incomplete. If no flame is detected, the boiler switches to safety shutdown after 3re-ignition attempts and displays the error code E01.

- Low water pressure switch (or hydraulic pressure switch): This device is used to ignite the burner only if the pressureinside the installation is higher than 0.5 bar. Otherwise, the boiler shuts down and shows the error code E10.

- Measurement of the gradient of the boiler temperature, measured by the boiler sensor:The burner stops if the boiler temperature gradient exceeds 5°C per second. In this case, the boiler shuts down and displaysthe error code E25. Cut-off because of the gradient is activated 12 seconds after the flame is detected by the electrode if theboiler temperature exceeds 42°C. The anomaly is temporary but, if the error is duplicated more than 3 times, the boiler shutsdown and the error code E25 is displayed steadily on the readout. This may occur if there is air in the heating circuit or if thereis no water circulation or insufficient circulation in the primary circuit.

- Measurement of the over-temperature in heating mode, measured by the boiler sensor: In heating mode, the burnerstops when the boiler temperature exceeds the heating set point temperature by 20°C. In this case, the boiler shuts downand displays the error code E26. The anomaly is temporary but, if the error is duplicated more than 3 times, the boiler shutsdown and the error code E26 is displayed steadily on the readout. This may occur if there is no water circulation or insufficientcirculation in the primary circuit.

- Heating circuit safety valve: This device is calibrated to 3 bar and controlled by the heating circuit. - Safety valve on the DHW circuit: This device is calibrated to 7 barScenario with MS 24 MI VMC boilers (for France only):

The MS 24 MI VMC boiler is fitted with a special device used to makethe connection to a unit that mechanically extracts combustionproducts. Operating principle: - A thermostat is placed in the draught diverter. - When the burner is ignited and the fan is running normally, the

thermostat is swept by the ambient air. - If the ventilation becomes faulty (either because of a fan

breakdown, an obstruction in the duct or extraction outlet, or forany other reason), the flow rate of ambient air diminishes and thetemperature at which the combusted air and gas are mixedincreases immediately; The draught diverter thermostat cuts offthe electrical circuit, causing the gas inlet to be locked down. Thisbrings about a boiler safety lockout and the error code E03 isdisplayed.

The appliance is shut down and cannot start up again until after amanual intervention. After checking the ventilation circuit (duct, fan, etc.), it will be possible to reset the boiler. Collective safety device (DSC):This boiler can, where present, be connected to the gas VMC collective safety device (this device is in no event a substitute forthe device integrated in the boiler). The mains supply to the boiler (230 V 50 Hz) is done by a specific line, controlled by a safety relay, independent of the boiler andlocated in the room to be heated. The safety relay itself is managed by the control device (pressure switch, tachometer, etc.) forthe collective VMC. If the latter breaks down, the mains supply to the boiler will be interrupted, temporarily shutting off the gas supply to the burner.The appliance is in the OFF position and will start up again automatically after the fault has been cleared.

29

3

PRODUCT EVOLUTION

31

3

Contents

1. Product launch date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

2. Modifications - Technical information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

32

3

1. Product launch date

Appliance Date Details

MS 24MS 24 MIMS 24 FFMS 24 MI FF

From: February 2011 Commercialization in FRANCECommercialization in other countries

MS 24 MI VMC From: February 2011 Commercialization in FRANCE

MS 24 BICMS 24 BIC FF From: May 2011 Commercialization in FRANCE

Commercialization in other countries

33

3

2. Modifications - Technical information

2.1 IT2581 - New disconnector

2.1.1 Description of the modificationFollowing the change in supplier, the WATTS disconnector will be replaced by a CALEFFI disconnector and a newconnecting tubing, on the whole MS boiler range.

Forecasted application date in production: February 2012.

2.1.2 Spare parts

A new set with pipe + disconnector + gaskets is available and already delivered in spare parts , to replacethe old disconnector:

Previous version - WATTS New version - CALEFFI

Appliance typeReferences in spare parts

Exploded view Marker Reference Description

MS 24 BICMS 24 BIC FFMS 24 MI VMC

MS 24 MIMS 24 MI FF

New version (CALEFFI disconnector)236 JJD710877800 CALEFFI disconnector + Pipes + Gaskets234 JJD710795501 Disconnector pipe - CALEFFI622 JJD710795401 Disconnector pipe - CALEFFI

Previous version (WATTS disconnector)234 JJD710395200 Disconnector pipe - WATTS

622 JJD710395300 Disconnector pipe - WATTS

MS 24MS 24 FF

New version (CALEFFI disconnector)236 JJD710876000 CALEFFI disconnector + Pipe + Gaskets234 JJD710755501 Disconnector pipe - CALEFFI

Previous version (WATTS disconnector)234 JJD005659050 Disconnector pipe - WATTS

236

234

34

4

TROUBLESHOOTING DIAGRAMS

37

4

Contents1. Checks to make before carrying out any work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

2. Error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3. Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

38

4

1. Checks to make before carrying out any workBefore carrying out any work on the boiler because of a breakdown, the following points must be checked:

Check the hydraulic connectionsCheck the hydraulic pressure in the circuit Check that the air has been correctly purged from the installationCheck the inflation pressure of the expansion vesselCheck that the installation is cleanCheck the mains supply voltage (Respect live / neutral )Check that there is no parasitic current on the earthing (Neutral / Earth)Check that the combustion gases are adequately evacuated and that the diameter of the diaphragm is correct, ifnecessary.

See section 5, chapter 4Check the gas pressure (Gas supply pressure - Nozzle pressure)

See section 6, chapter 6

39

40

4

2. Error codesIf a malfunction occurs, the control panel displays an error code.

To reset the boiler: Press the R key for at least 2 seconds.If the fault is not cleared: Correct the malfunction of the appliance. Refer to theappropriate synoptic (see below)

The boiler stops automatically after the fifth attempt to reset it. To carryout another attempt to reset it, switch the boiler off for a few seconds.

Error code Type of malfunction Causes / Corrections

E01Gas supply or ignition error. Check the gas supply. Check the condition and connection of the

ignition and ionisation electrode cable.Refer to the appropriate synoptic.

E02 Safety thermostat tripped. Overheating alarm.

Check the safety thermostat. Refer to the appropriate synoptic.

E03

Flue gas thermostat tripped (all versions excepted FF) /Air pressure switch (FF Versions). The burner is off.

• FF Versions (Air pressure switch): flue gas extraction terminal blocked, venturi blocked, fan blocked, venturi-pressure switch connection interrupted. Correct it.

• MS 24 - 24 MI - 24 MI VMC Versions (Flue gas thermostat) :- Chimney blocked: Clean.- No draught: make sure there is some draught.

E04 Malfunction after the flame going out unexpectedly 6 times (loss of flame signal).

Press the R key for at least 2 seconds.Refer to the appropriate synoptic.

E05

Breakdown of the CTN heating sensor. Check the CTN heating sensor. If the sensor is damaged:- If running, the boiler shuts down- The fan stops after 10 seconds- The pump continues to run for 3 minutes. This error is cleared automatically when the sensor is replaced.

E06

Breakdown of the CTN domestic hot water sensor.

Check the CTN domestic hot water sensorNote: If the CTN sensor on the DHW circuit breaks down, hot water production continues nevertheless. The temperature will be controlled by the heating sensor. The heating function continues to operate. This error is cleared automatically when the sensor is replaced.

E10 The water pressure is too low. The hydraulic pressure switch enables burner ignition only if the

pressure in the installation is higher than 0.5 bar.Check the water pressure.

E12 The hydraulic pressure switch micro-switch always remains open.

Refer to the appropriate synoptic.

E13 The hydraulic pressure switch micro-switch always remains closed.


Fault that can be reset

4

E25

Maximum boiler temperature exceeded. Anomaly because of too high gradient.

The burner stops if the boiler temperature gradient exceeds 5°C per second. The display shows the error code E25. Cut-off because of the gradient is activated 12 seconds after the flame is detected by the electrode if the boiler temperature exceeds 42°C. The anomaly is temporary but, if the error is duplicated more than 3 times, the boiler shuts down and the error code E25 is displayed steadily. This may occur if there is air in the heating circuit or if there is no water circulation or insufficient circulation in the primary circuit.- Check that the plug in the automatic air vent located on top of the

heating pump body is open.- Check that there is sufficient flow rate in the installation.

E26

Maximum boiler temperature exceeded. Anomaly for overheating.

In heating mode, the burner stops when the boiler temperature exceeds the heating set point temperature by 20°C . In this case, the display shows the error code E26. The anomaly is temporary but, if the error is duplicated more than 3 times, the boiler shuts down and the error code E26 is displayed steadily. This may occur if there is no water circulation or insufficient circulation in the primary circuit.

E31 Communication error between the boiler and the remote control.


E32 Scaling alarm. Presence of limescale in the exchanger.

Descale the appliance (See section 6, chapter 4.3 / 4.4). Press the R key for at least 2 seconds.

E35 Flame presence anomaly (Parasite flame) Refer to the appropriate synoptic.

E36 Parasite flame or flame anomaly Refer to the appropriate synoptic.

E96 Power cut due to fall in voltage (voltage less than 170 Volts)

Automatic reset.

E97 Mains supply frequency anomaly (Hz) Automatic reset.

E98 - E99 Internal error on the PCB Replace the PCB.

Error code Type of malfunction Causes / Corrections

41

4

3. Diagrams

Symbols used:

Before repair work:- Check the good state of the fuses- Ensure that all connectors are engaged, that there are no loose wires, by pulling them gently,

nor any trapped or damaged wires.

Before and after each intervention : - Check and ensure that the sensor and 230 V cables are separated.

Fault displayXXX FAULT

END

Check to be made (yes/no)

Processing to be carried out or comment

End of processing

42

4

3.1 No DHW production

(1) A08 = l/min x 10

No DHW production.

END

Replace defective parts.

no

yes

• Check if the boiler is in Heating Only or OFF/Frost Protection position: Select the appropriate operating mode: Summer ( ) or Winter ( ).

• MS 24 (FF) + DHW tank BMR.../ SR...: Check that parameter F03 is correctly set to 03. See section 5, chapter 7.5.

• Establish a DHW flow rate of > 2 l per min.

Check whether parameter A08(1) shows the corresponding value. Check the reversal valve and

its wiring.

no

yes

Replace the PCB.

Check the flowmeter and its wiringSee section 6, chapter 5.3.

noOK ?

yes

Rectify the settings Check the condition of the cold water valve, the filters,

the flowmeter, the plate exchanger and the reversal valve.

OK ?

Clean / replace the defective part(s).

43

4

3.2 E01: Gas supply or ignition error

3.3 E02: Safety thermostat tripped

3.4 E03: Flue gas evacuation defect

E01 fault Gas supply or ignition error.

END

See section A - page 49noOK ?

yes

To reset the boiler: Press the R key for at least 2 seconds.

E02 fault Safety thermostat tripped.

END

Check the safety thermostat and its wiring.See section 6, chapter 5.4.

noOK ?

yes

- Overheating due to a lack of flow rate: All the radiators are closed.- Vent the air in the heating system. Check that the plug in the automatic

air vent located on top of the heating pump body is open.- To reset the boiler: Press the R key for at least 2 seconds.

E03 fault Flue gas thermostat (all versions except FF) or air

pressure switch (version FF) tripped. The burner is off.

END

All versions: See section E - page 51.FF Versions : See section C page 50.

noOK ?

yes

To reset the boiler: Press the R key for at least 2 seconds.

44

4

3.5 E04: loss of flame signal

3.6 E05 or E06: Sensor fault

E04 fault Malfunction after the flame going out unexpectedly 6

times.

END

See section C - page 50.noOK ?

yes

To reset the boiler: Press the R key for at least 2 seconds..

E05 / E06 fault - Breakdown of the CTN heating sensor.- Breakdown of the CTN domestic hot water sensor.

END

Replace the defective sensor.noOK ?yes

Measure the resistance of the sensor on the connector terminals.

See section 6, chapter 5.2.

Check the harness

Replace the harness.OK ? no

yes

Replace the PCB.

45

4

3.7 E10, E12, E13: Hydraulic pressure switch defect(Low water pressure switch)

no

OK ?yes

- If necessary, top up the water level in the heating system (recommended hydraulic pressure between 1 and 1.5 bar)- Check that the plug in the automatic air vent located on top of the heating pump body is open;- Carry out maintenance on the boiler (Clean the filters, Exchanger...).

E10 fault: The water pressure is too lowE12 fault: Pressure switch contact remains openE13 fault: Pressure switch contact remains closed.

Check continuity on the hydraulic pressure switch terminals (Normally open

contact): See section 6, chapter 5.6.

END

no

Check the wiring.

OK ? Replace the harness.

yes

no

yes

Replace the PCB.

Replace the hydraulic pressure switch.Contact open ?

46

4

3.8 E25, E26: Maximum boiler temperature exceeded

E25, E26 fault E25: Anomaly because of too high gradient. Water

circulation fault.E26: Maximum boiler temperature exceeded.

END

Replacing the pump.

no

yes

Unblock the heating pump. Check that the heating pump is operating correctly:See section 6, chapter 5.9.

The pump operates ?

Check the power supply to the pump (230 V) at the outlet on the PCB

(Terminals 6 - 7).Replace the PCB.no

yes

Replace the pump wiring.

Check pump operation (Power it separately).

noOK ?

yes

See section Bpage: 49.

- Check parameters F08 and F09: Recommended value = 100- Vent the heating installation.Check that the plug in the

automatic air vent located on top of the heating pump body isopen.

47

4

3.9 E31: Communication fault

3.10 E35 or E36: Parasite flame fault

E31 fault Communication error between the boiler and the

remote control.

END

See section Apage: 49.

noOK ?

yes

Check the room thermostat if fitted.If the room thermostat is not in use: check that the bridge

is fitted to the connection terminal block.

E35 / E36 fault Parasite flame or flame anomaly.

END

See section D - page 50.noOK ?

yes

Check the settings on the gas valveSee section 6, chapter 6.

48

4

3.11 Sections

A - Defects E1, E31 or no display.

B

Check live-neutral compliance = 230 V and neutral-earth = 0 V.

Check the fuses on the control panel. Replace if necessary.

Check the room thermostat if fitted.If the room thermostat is not in use: check that the bridge is fitted to the connection

terminal block. no

ENDyes

Replace the PCB.

- Reset by pressing the R key forat least 2 seconds.

- Press . Choose position or (Press for 2 seconds tochange function).

Check that the gas supply is available and that the gas pipe is sufficiently vented.

Display OK ?

Check that there is no voltage between neutral and earth (< 5 V). < 5 V? yes See section D - page 50.

noAppliance or cable defective in the electrical installation:- Replace or repair the electrical problem with the

installation- Fit a circuit separation transformer.

Check the cleanliness of the heat exchanger.Carry out maintenance on the boiler. Clean

the filters.See section 6, chapter 4;

no

ENDyes

Replace the PCB.

- Reset by pressing the R key for atleast 2 seconds.

- Press . Choose position or (Press for 2 seconds to

change function). Display OK?

Check continuity on the hydraulic pressure switch terminals.

See section 6, chapter 5.5ok ?

yes

Replace the hydraulic pressure switch.

no

49

4

C

D

- Check the fan wiring.- Check the power supply to the fan at the

oultet on the PCB (230 V AC)See section 6, chapter 5.11.

no

yes Replace the fan.Fan blocks or does not rotate correctly?

Check the settings on the gas valve.

END- Check the venturi pipe - Check the air pressure switch

connections.OK ? Refurbish / Replace.no

yes

Check the ionization/ignition electrode:- Position- Visual inspection (state of wear)- Wiring- Check that the voltage on the electrode

terminal block on the PCB is 230 V.

no

yes Replace the ignition electrode / ionisation sensor.OK ?

Replace the PCB.

END

50

4

EThe flue gas thermostat has tripped or isdefective. Check continuity on the flue gasthermostat (all versions except FF) or the airpressure switch (versions FF) terminals.

no

yes

Replace the flue gas thermostat (all versions except FF) or the air pressure

switch (versions FF).

continuity?

Check the resistance on the flue gas thermostat or air pressure

switch terminals.

END

Resistance > 1.5 Ohm.

Replace the harness.

yes

no Replace the board / electronics circuit.

51

5

INSTALLATIONCOMMISSIONING

G000008

53

5

Contents

1. Location of the appliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 551.1 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 551.2 Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

2. Hydraulic connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562.1 Water treatment in the heating circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 562.2 Installing the boiler in new installations (installations less than 6 months old) . . . . . . . . . . . . . . . . . . . . . . . 572.3 Installing the boiler in existing installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572.4 Hydraulic connections (Heating circuit, DHW circuit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 582.5 Connecting the expansion vessel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 582.6 Connecting a solar DHW tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 592.7 Expansion vessel DHW circuit (Option) - MS 24 BIC (FF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

3. Gas connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613.1 Connecting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613.2 Gas categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

4. Connecting the flue gas pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624.1 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624.2 Concentric air / flue gas connection (FF Versions) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

5. Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

6. Filling the installation with water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

7. Check points before commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 687.1 Checking the gas supply pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 687.2 Check the hydraulic circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697.3 Bleed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697.4 Check the electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697.5 Parameter settings - MS 24 (FF) - MS 24 MI (FF / VMC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 707.6 Parameter settings - MS 24 BIC (FF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

8. Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 738.1 Commissioning procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 738.2 The boiler does not start up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 738.3 In the event of run-off noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

54

5

1. Location of the appliance

1.1 LocationThe boiler must be installed in a frost-free environment. Do not place the appliance above a heat source or a cooking appliance.The IPX5D protection rating allows the boiler to be installed in a kitchen or bathroom .

The warranty does not apply to damage to the boiler caused by these instances.

1.2 VentilationTo ensure adequate accessibility to the appliance and facilitate maintenance,leave enough space around the boiler. The minimum recommended dimensionsare shown in the illustration in mm.

If the heating appliance is installed in residential premises where people are present all the time, ensure sufficient ventilation pursuant to prevailing regulations.

MS 24, MS 24 MI, MS 24 MI VMC, MS 24 BICDo not block (even partially) the ventilation vents in the room in which the appliance is installed.

Fresh air inlet:France: In the event of direct air inlet, the cross-section of the fresh air inlet, whichis compulsory, must have a minimum surface area of 50 cm2 (NF P 45.204).Other countries: the cross section of the aeration inlet, which is compulsory inthe premises in which the boiler is installed, must comply with the standards inforce in the country.

Evacuation of polluted air:When the boiler is installed in a kitchen, for example, the evacuation of pollutedair from appliances not connected to a discharge flue (e.g. gas cooker) can behandled by the boiler's draught cut-off. To do this, it is sufficient for the top of the boiler casing to be positioned at least 1.8 mmfrom the floor.If located in a closed cubby hole, ensure ventilation of the cubby hole itself with a minimum total cross section of 600 cm2. Theminimum distance between the front of the boiler and the door or closing panel must be 10 cm.S1 + S2 = 600 cm2

MS 24 ... FFIf combustion gas evacuation and combustive air intake are done using a concentric pipe (connection type C12 or C32), ventilationof the room in which the appliance is installed is not necessary unless the gas supply comprises one or more mechanicalconnections (see NF P 45.204).

In order to avoid damage to the boiler, it is necessary to prevent the contamination of combustion air by chlorineand/or fluoride compounds, which are particularly corrosive. These compounds are present, for example, inaerosol sprays, paints, solvents, cleaning products, washing products, detergents, glues, snow clearing salts,etc.Therefore:

- Do not pull in air evacuated from premises using such products: hairdressing salons, dry cleaners,industrial premises (solvents), premises containing refrigeration systems (risk of refrigerantleakage), etc.

- Do not stock such products close to the boilers.If the boiler and/or peripheral equipment are corroded by such chloride or fluoride compounds, thecontractual guarantee cannot be applied.

100

mini

25min.

25min.

730

min. 250

min. 200

S1

S2

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2. Hydraulic connectionsIf an extra pump is used on the heating system, it must be fitted to the boiler's return circuit in order that the hydraulic pressure switch can operate correctly.

The installation must comply in all matters to the standards and rules which govern the work and interventions in individual andcollective homes, and other constructions. The boiler must be used only in closed circuit heating installations.

2.1 Water treatment in the heating circuitCentral heating systems must be cleaned to eliminate debris (copper, strands, brazing flux) linked to the installation of the systemand deposits that can cause malfunctions (noise in the system, chemical reaction between metals). On the other hand, it isimportant to protect central heating systems against corrosion, scaling and microbiological growth by using a corrosion inhibitoradapted to all types of systems (steel, cast iron radiators, heated floor, PER).For Switzerland : The water quality must comply with the SICC directives No. 97-1F "Treatment of water intended for heating,steam, refrigeration and air conditioning installations".

Specifications required for the heating water:The characteristics of the heating water are essential to guarantee good performance, operating safety and the longevity of theequipment used. Poor water quality in the heating circuits may damage the installation by leaving limescale deposits or causingcorrosion.To implement a condensing boiler with an aluminium-silicium heating body, we recommend the limiting values of the principalcharacteristics of the heating water with reference to the requirements of prevailing regulations(1):

- pH 6.5 to 8.5,- Conductivity < 500 µS/cm at 25°C.- Chloride content < 20 mg/l,- Suspended particles < 20 mg/l.

The requirements on water hardness are directly related to the total volume of the installation. The limiting value takes the installedoutput as its frame of reference. In the case of a cascade installation, the reference will be the limiting value of the water used forinitial filling corresponding to the smallest boiler.

(1) For Germany: VDI 2035Recommendations:

- If the aforementioned conditions are not met or to provide additional protection to the unit (network, radiators, etc.), it will benecessary to resort to water treatment in the installation (product, filtration and tracking of parameters), which will factor in thevariety of materials present, including the aluminium heating body.

- Take any precautions necessary to prevent the introduction into and formation of oxygen in the water in the installation by checking that the expansion vessel, the safety valve(s), etc. are correctly sized- Antifreeze products: ensure that these are compatible with aluminium and, if need be, with other components in the installation.

- Limit topping up the installation with water to the minimum. If using treatment, check the properties of the water and theconcentrations of active substances in the installation at least 2 times a year.- De Dietrich Thermique recommends the following manufacturers: Cillit - Climalife - Permo - Sentinel.

Water hardness

Useful output Pn (kW) Concentration°dH °f

≤ 70 2.8 - 20 5 - 2070 - 200 2.8 - 20 5 - 15

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2.2 Installing the boiler in new installations (installations less than 6months old)

- Clean the installation with a universal cleaner to eliminate debris from the appliance (copper, hemp, flux).- Thoroughly flush the installation until the water runs clear and shows no impurities.- Protect the installation against corrosion and frost with an inhibitor and an anti-freeze.

2.3 Installing the boiler in existing installationsIf renovating an old network, we recommend checking the compliance of the characteristics of the existing water and, whereapplicable, removing any sludge and rinsing before installing the new boiler.- Remove sludge from the installation.- Clean the installation with a universal cleaner to eliminate debris from the appliance (copper, hemp, flux).- Thoroughly flush the installation until the water runs clear and shows no impurities.- Protect the installation against corrosion and frost with an inhibitor and an anti-freeze.- Fitting a filter or an appropriate decanting pot to the installation's return circuit should prevent the deposit of suspended particles in the

generator body

The boiler must be used only in closed circuit heating installations.

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2.4 Hydraulic connections (Heating circuit, DHW circuit)

The water connections to the boiler must be made with a maximum torque of 30 Nm.

2.5 Connecting the expansion vesselMS... : The boiler is fitted as standard with an 6-litre expansion vessel. MS... BIC : The boiler is fitted as standard with an 7.5-litre expansion vessel

Initial pressure of the expansion vessel: 1 bar.Average water temperature: 85 °CFlow temperature: 95 °CReturn temperature: 75 °C

MS 24 (FF) MS 24 MI (FF) MS 24 BIC (FF))

Ref./ Marking MS 24 (FF) Ref./

Marking MS 24 MI (FF, VMC), MS 24 BIC (FF)

Heating flow - G 3/4 (Ø 18 mm internal)

Heating flow - G 3/4 (Ø 18 mm internal)

Primary flow to DHW tank (if present) - G 3/4 Domestic hot water outlet - G 1/2 (Ø 16 mm internal)

Gas inlet - G 3/4 (Ø 18 mm internal) Gas inlet - G 3/4(Ø 18 mm internal)

Primary return, DHW tank (if present) - G 3/4 Domestic cold water inlet - G 1/2(Ø 16 mm internal)

Heating return - G 3/4 (Ø 18 mm internal)

Heating return - G 3/4(Ø 18 mm internal)

Domestic cold water inlet - G 1/2(Filling valve)

MS 24 (FF)MS 24 MI (FF, VMC)

Nominal pressure of the expansion vessel (bar) 0.5 0.6 0.7 0.8 0.9 1

Maximum volume of the installation (litres) 110 105 95 86 78 70

MS 24 BIC (FF)

Nominal pressure of the expansion vessel (bar) 0.5 0.6 0.7 0.8 0.9 1

Maximum volume of the installation (litres) 135 130 120 105 95 85

2 3 45

71

G000

378

G000

379

2 45 3421

G000

380

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2.6 Connecting a solar DHW tankHyrdaulic connection kit for a solar circuit with directional thermostatic valve (Optional delivery for MS 24 MI... only)

Thanks to this kit (which includes a directional thermostatic valve), water coming from the solar tank passes through the boiler onlywhen the water temperature is lower than a preset value (48°C, for example). The boiler will handle any additional heating of thewater to the required temperature.

Option HX23

Hydraulic boiler connection plateHot water inlet from the boilerHot water inlet from the solar DHW tankCold water inlet from the boilerDomestic hot water outlet - G1/2Domestic hot water inlet - G1/2Cold water inlet sectional valveDirectional thermostatic valve

65

1

65 656565

208

2

3

4

5 6

8

7

G000451

60

5

2.7 Expansion vessel DHW circuit (Option) - MS 24 BIC (FF)We recommend mounting the DHW expansion vessel in the following cases:- If a pressure reducer has been fitted (if the domestic cold water mains pressure is higher than 4 bar).- If a non-return valve is fitted to the cold water supply.- If the cold water supply circuit is insufficient to enable the expansion of the hot water contained in the boiler's storage tank andit is necessary to provide for the use of a DHW expansion vessel.

Important: To ensure that the expansion vessel operates correctly, the pressure on the cold water inlet must be less than 4 bar.If this is not the case, fit a pressure reducer. The pressure reducer must be set so as to provide a water supply pressure of lessthan 4 bar.

The expansion vessel on the DHW circuit is connected to points A and B as shown in the diagram above.

1. Remove the plug2. Put the end piece and the hose in place

1

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3. Gas connection3.1 Connecting

CautionCheck that the boiler is properly set for the type of gas used. For further details, see the appliance's rating plate. See also below: Heading 6, Chapter 6 - Gas settings - Adapting to another gas type.Close the main gas valve before starting work on the gas pipes.Before mounting, check that the gas meter has sufficient capacity. To do this, you should keep in mind the consumption ofall domestic appliances. If the gas meter has a too low capacity, inform the energy supply company.Ensure that there is no dust in the gas pipe. We recommend installing a gas filter on the gas pipe to prevent clogging of the gas valve unit. Connect the gas pipe in accordance with prevailing standards and regulations.

3.2 Gas categoriesFor France

The boilers are factory-set to operate on natural gas (H (G20) or L (G25))

For ItalyThe boilers leave the factory operating with H natural gas (G20)

For SpainThe boilers leave the factory operating with H natural gas (G20)

For PolandThe boilers leave the factory operating with E natural gas (G20)

For other countries: see the nameplate or the instructions supplied with the appliance.

Boiler type Gas category Gas type Connection pressure (mbar)MS 24 (FF)MS 24 MI (FF)MS 24 BIC (FF)

II2E+3P

Natural gas H (G20) 20Natural gas L (G25) 25

Propane (G31) 37

MS 24 MI VMC I2E+Natural gas H (G20) 20Natural gas L (G25) 25


II2H3PNatural gas H (G20) 20

Propane (G31) 37


II2H3PNatural gas H (G20) 20

Propane (G31) 37

Boiler type Gas category Gas type Connection pressure (mbar)

MS 24 (FF)MS 24 MI (FF)MS 24 BIC FF

II2ELWLs3P

Natural gas E (G20) 20Natural gas Lw (G27)Natural gas Ls (G2.350) 13Propane (G31) 37

MS 24 BIC II23PNatural gas E (G20) 20Propane (G31) 37

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4. Connecting the flue gas pipe4.1 Installation- The boiler must be connected in compliance with prevailing provisions and standards, i.e. with conduits intended to evacuate pressurized

flue gases.- The pipes must allow no leakage of flue gases and be resistant to corrosion. They must be installed in such a way that their relative position

in relation to the special evacuation system cannot be modified even after service interventions.- The appliance, including its connection conduit, must remain accessible with a view to maintenance and repair.

CautionFor France: Boilers can only be installed with flue gas connection pipes provided by the constructor. For other countries: the boiler must be connected with an approved flue gas system.The clear section must comply with the standard.The chimney must be swept before the installation of the evacuation conduit.

MS 24, MS 24 MI, MS 24 BIC (Chimney versions)The cross section of the chimney duct must be at least equal to that of the boiler's flue gas nozzle (Diameter 125 mm). Theconnection to the chimney must be as short and as direct as possible.

MS 24 MI VMC (Model available only in France): Connection to the mechanically controlled ventilation system (MCV-gas flue)

MS 24 MI VMC wall-hung boilers are designed to be connected as follows:• Connection to a mechanical ventilation system in tandem with the stale air discharge, or• Connection to a mechanical extraction system for the boiler combustion products only.These connection systems apply equally in collective buildings and individual homes and must satisfy prevailing standards bothin terms of commissioning and of maintenance.In accordance with the NF D 35-337 standard, MS 24 MI VMC boilers are fitted with an internal device that cuts off the gas supplywhen the draught from mechanical extraction becomes insufficient.However, if the flue serves one or more levels other than the one on which the MS 24 MI VMC boiler is connected, the installationof a Collective Safety Device (DSC) is compulsory.

MS 24 FF, MS 24 MI FF, MS 24 BIC FF - Air/flue gas connectionMS 24... FF wall-hung gas boilers are sealed appliances to be connected according to one of the following configurations:

Maximum length = lengths of the straight air/flue gas ducts + equivalent lengths of other components.

For the installation of the air/flue gas connection ducts, details of the various configurations and the installation rules, see the "FlueSystems" document.

Configuration C12x Configuration C32x Configuration C52 Configuration C42x

Lmax

G000352

Lmax

Lmax = L1+L2+L3

L3

L1

L2max 2 m

G000353

LF

LA

Lmax = L A + L F

LA max = 10 m

G000

354

Lmax

G000

355

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4.2 Concentric air / flue gas connection (FF Versions)

4.2.1 Maximum length for the air/flue connection pipes

Table of the maximal acceptable lengths of the air/flue connection pipes

On concentric flue gas discharge systems (forced flue), the C02 level in the annular space in the measurement piping canalso be checked. The flue gas discharge system is considered leak-proof if the measured CO2 level is lower than 0.2% (Whenthe boiler operates at maximum output).

Equivalent conduit lengths (metres) - flue gas system delivered by De Dietrich Thermique

Type of air/flue gas connection Diameter Maximum length Lmax (m)

C12xConcentric pipes connected to a horizontal terminal Alu

60/100 mm 480/125 mm 10

C32xConcentric pipes connected to a vertical terminal Alu 80/125 mm 9

C52Bi-flow adapter and separate single air/flue gas ducts (combustive air taken from outside) Alu 60/100 mm

2 x 80 mm 30

C42x Collective conduit for sealed boiler (3CE) Alu 60/100 mm 4

Connection diameter (in mm) Ø 60/100 Ø 80/125 Ø 60 - rigid Ø 80 - rigid (Alu)

Ø 80 - Flexible

Elbow 87° 1.1 1.5 1.1 1.2 -Elbow 45° 0.8 1.0 0.6 0.9 -Elbow 30° 0.7 - 0.9 - -Elbow 15° 0.5 - 0.6 - -Right inspection tube 0.5 0.6 0.3 0.5 0.387° inspection elbow - 2.0 - -Inspection T 2.2 2.7 2.9 2.8Inspection tube for flexible pipe - - - - 0.3Condensate collector 60/100 mm (DY910) 1.4 - - - -Condensates adapter/recuperator Ø 60/100 onØ 80/125 (DY909) - 0.2 - - -

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4.2.2 Diaphragm on flue gas duct for concentric connectionThe concentric duct is used to evacuate combusted gases to the outside and to supply the boiler with combustive air. The 90° coaxial elbow can turn around 360° and can be used to connect the boiler to the intake/discharge duct in any direction.It can also be used as an extra elbow in combination with a coaxial duct or a 45° elbow.

The first 90° elbow is not taken into account in calculating the maximum length available.The end of the duct comes out outside the building and must clear the brickwork to allow for installation of the aluminium coverplate and its seal and prevent any water infiltration. The minimum gradient of these ducts towards the outside must be 1 cm permetre of length.

Using the flue gas duct diaphragm and dimensions:

Boiler type Concentric evacuation/intake connection diameter (mm)

Length(m)

Using a diaphragm on the intakediameter (mm)

MS 24 FFMS 24 MI FF

60 / 100 0 to 1 801 to 4 NO

80 / 125 0 to 10 90

MS 24 FF BIC60 / 100 0 to 1.5 76

1.5 to 5 NO80 / 125 0 to 5 80

5 to 10 NO

A: DiaphragmB: Fixing clamp

A

B

64

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4.2.3 Separate evacuation/intake connections (FF Versions)This type of installation makes it possible to separate the intake and evacuation flows into separate ducts coming out outside thebuilding. The combustive air intake and the flue gas evacuation terminal can be located in different places. The separation kit includes an evacuation duct adapter (100/80) and an intake duct adapter. To install the intake duct adapter, usethe screws and the gasket previously removed from the obturator.

Setting the air flow rate in a separate ductIt is necessary to set the air flow rate to optimise the operating and combustion parameters. The air intake connection can beturned to set the air inlet according to the total length of the intake and evacuation ducts.Turn it to increase or reduce the air quantity as needed. For a more accurate setting, use a combustion products analyser to measure the CO2 content at the maximum heat produced bythe boiler. Set the air intake in such a way as to obtain a CO2 value that matches the indications in the table below.

Boiler type LA + LF(m)

Air intake setting position (mm)

CO2 (in %)G20 G25 G31

MS 24 FFMS 24 MI FF

0 to 4 17.2 7.2 84 to 18 2

18 to 30 3

MS 24 BIC FF0 to 20 1

6.1 6.1 8.720 to 30 2

Diaphragme d’aspiration

Position of the diaphragm

Intake diaphragmLF

LA

Lmax = L A + L F

LA max = 10 m

G000

354

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5. Electrical connections- Any interventions inside the boiler must be done by a qualified and authorised person- Before any interventions, ensure that the electrical power is disconnected. - Only qualified professionnals may carry out electrical connections, always with the power off. - The electrical connections shall comply with standards in forceThe earthing must comply with the NFC 15.100 (France) or the RGPT (Belgium) standards.- The equipment must have a power supply equipped with a omnipolar switch with an opening distance above 3 mm. Protect theconnection to the mains with a 6 amp fuse.- Under no circumstances must sensor cables (very low voltage) be placed in cable ducts or channels carrying cables supplying230 V. Furthermore, a minimum distance of 10 cm should be kept between cables supplying very low voltage and cablessupplying 230 V.

If replacing the power cable, use a regulation HAR HO5 VV-F cable of 3x0,75 mm2 with a maximum diameter of 8 mm.Keep to the polarity shown on the terminals: phase (L), neutral (N) and earth .

Access to the connection terminal: Cut the power supply to the boilerUnscrew the 1 / 2 holding screws in the control panel. Tilt the control panel.Open the cover (1 screw) to access the terminal block for the electrical connections .

MS 24 (FF), MS 24 MI (FF), MS 24 VMC

FusesThe quick type 2 A fuses are incorporated in the power supply terminal block. Pull out the black fuse holder to check them and/orreplace them.

ChecksCheck the polarities shown on the terminals: live (L), neutral (N) and earth ( )Check that the difference in potential between earth ( ) and neutral (N) is 0. Otherwise, review the earthing. Check the electrical connections to the thermostat and the other external controls.

MS 24 BIC (FF)

FusesScrew

Electrical connection: 230 V, 50 Hz. (L) : Live (Brown)(N): Neutral (Sky blue)( ): Earth (Yellow - Green)(Terminals 1 - 2): Connecting the room temperature thermostatFuses: 2 A

Fuses

G000367

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6. Filling the installation with water

1. Open the cold water inlet and heating outlet valves. We recommend opening the valves very slowly to facilitate air venting.2. Open the disconnector valves (During filling, air can escape from the system via the automatic air vent).3. Close the disconnector valves when the manometer indicates a pressure of 2 bar.4. Checking the water-side connections for tightness.

Regularly check that the water pressure in the installation is between 0.7 and 1.5 bar.

After filling and priming all circuits with water:Completely disgas the boiler and the installation for optimum operation.

The first start-up is to be performed by your installation/commissioning engineer. The boiler is fitted with a hydraulic safety device that prevents its operation without water.

Switch off the mains supply

Before filling, open the valves on every radiator in the installation.Water treatment in the heating circuit: See section 5, chapter 2.1.

A Drain cockB Pressure gaugeC Filling valve

MS 24 (FF): D Disconnector

A Drain cockB Tank drainage valveC Filling valveD Pressure gauge

1 2

3

4

T000181-B

MS 24 MI (FF) - MS 24 MI VMC MS 24 (FF)

G000394

MS 24 BIC (FF)

5

7. Check points before commissioning

7.1 Checking the gas supply pressureCheck that the gas type supplied matches the data shown on the boiler's data plate.Caution: Do not put the boiler into operation if the supplied gas is not in accordance with the approved gas types. To ascertain the gas types permitted, see chapter: Gas categories - Heading 5 - Chapter 3.2.

.

The first start-up is to be performed by your installation/commissioningengineer.

Water treatment in the heating circuit: As most heating systems are designed from various materials, itis recommended to provide a water treatment to prevent or reduce the problems (metal corrosion,formation of scale and sludge, microbiological contamination, chemical changes in the untreated systemwater).See section 5, chapter 2.1.

If the pressure exceeds the authorised pressure range: - Natural gas G20 = 17-25 mbar,- Natural gas G25 = 20-30 mbar;- Propane G31 = 37-50 mbar)

Suspend commissioning. Inform the gas supply company.

MS 24 MI... MS 24 BIC ...

Caution: Ensure that the boiler is switched off.1. Open the main gas supply.2. Unscrew the two screws located under the front panel by a quarter turn and remove the panel.3. Tilt the control panel (screwed down) to access the gas valve.4. Check the gas supply pressure at the pressure outlet Pa on the gas valve unit - Connect the manometer.5. Check the tightness of the gas connections made after the gas valve unit in the boiler.6. Check the tightness of the gas line, including the gas valves.7. Purge the gas supply pipe within the boiler by unscrewing the pressure outlet on the gas block. Tighten the measurement

point when the pipe has been sufficiently purged.

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7.2 Check the hydraulic circuitCheck that the installlation and the boiler are adequately primed with water (See section 5, chapter 6).Check that there are no leaks on the hydraulic connectionsCheck the water pressure in the heating system. The hydraulic pressure must reach a minimum of 0.8 bar. If necessary, topup the water level in the heating system (recommended hydraulic pressure between 1.5 and 2 bar).Checking the hydraulic pressure: On the mechanical pressure gauge, located under the boiler.

7.3 BleedIt is essential to vent any air found in the boiler's internal circuit and in the system's circuit:

Open the gas inlet valve,Turn the boiler on,Check that the plug in the automatic air vent located on top of the heating pump body is open,Activate the operating mode Winter ( ) using the key; Activate a heat requirement by setting the heating and DHW set point temperatures or by setting the room thermostat; Alternate the heat requirement for the heating with the domestic hot water requirement by opening a hot water tap. If, after a few attempts at ignition, the boiler goes into safety lockout, the display shows the error code E01.To reset the boiler: Press the key for at least 2 seconds.Repeat the procedure at least two more times.

After venting the boiler circuit, proceed with initial commissioning.

7.4 Check the electrical connectionsSee section 5, chapter 5, page 66.

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7.5 Parameter settings - MS 24 (FF) - MS 24 MI (FF / VMC)To access the boiler parameters:

Press the - ( ) and - ( ) keys simultaneously for at least 6 seconds.The display shows the code "F01", alternating with the value of the parameter.

To modify the value of a parameter:Press the +/- ( ) keys to scroll through the parameters,Use the + and - ( ) keys to change the parameter value.Press the key to confirm the setting: The display shows MEM.Press the key to cancel a modification and retain the previous value : Thedisplay shows ESC.

Parameter settings - MS 24 (FF) - MS 24 MI (FF / VMC)

(1)To activate the antilegionella function, programme the F16 parameter to a value of between 55 and 67°C. When the function is enabled, the boiler's electronics system heats the water in the tank to a temperature greater than the value of F16 once a week. The function is tripped only if the water has never exceeded the value of F16 in the previous 7 days.

(2) MS 24 MI VMC (for France only) : No operation on propane.(3) Caution - MS 24 (FF) versions with independent tank: The F03 parameter must be set to 03.

Parameter descriptionsFactory setting

24 MI FF 24 FF 24 MI 24 MI VMC (2) 24

F01Boiler type10 = Leak proof box20 = Atmospheric gas burner

10 10 20 20 20

F02Gas type01 = Propane02 = Natural gas (with corresponding diaphragm)

02

F03

Hydraulic system00 = Production of instantaneous domestic hot water03 = Boiler with an independent DHW tank04 = Boiler for heating only13* = Production of instantaneous domestic hot water and plate exchanger heating for 24 h (See table below)14* = Production of instantaneous domestic hot water and plate exchanger heating for 1 h

* See table below

13 04(3) 13 13 04(3)

F04-F05 Parameter settings programmable relay 1 and 200 = No associated function 00

F06 Setting the maximum set point temperature (°C)00 = 85 °C - 01 = 45 °C (Do not modify) 00

F07 Inlet configuarion for domestic hot water priority : 00= Flow switch - Turbine flux Meter BITRON01= Flow switch - Turbine flux Meter FUGAS02= Not used

00 01 00 00 01

F08 Maximum boiler output during heating (0-100%) 100F09 Maximum boiler output in DHW (0-100%) 100

F10 Minimum heating output (0-100%) 00

F11 Waiting time before another ignition00 to 10 minutes (00=10 seconds,...) 03

F12 Troubleshooting: Last error which occured. see : Description of error codes. --F13-F14-F15 Factory data - Do not modify 00

F16Antilegionella function (with F03=03) 00 = Antilegionella function not activated (1)55...67 = Antilegionella function activated (Set temperature °C)

00

F17Selection heating pressure switch type00 = hydraulic pressure switch01 = Differential hydraulic pressure switch

00

F18 Factory data 00

É

5

MS 24 MI ... Versions: Parameter F03

Description

Adjustment

F03 = 13 Preheating: 24 h

F03 = 14 Preheating: 1 h

Factory setting Factory setting = DHW function : 3-star

Preheating 40 minutes after the last heating operationor 40 minutes after the last DHW demand 20 minutes after the last DHW demand

Heating temperature setting Heating temperature setting = DHW setpoint temperature + 13 K

Duration Permanent 1 hourDisplay The symbol appears and flashes

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7.6 Parameter settings - MS 24 BIC (FF)To access the boiler parameters:

Press the - ( ) and - ( ) keys simultaneously for at least 6 seconds.The display shows the code "F01", alternating with the value of the parameter.

To modify the value of a parameter:Press the +/- ( ) keys to scroll through the parameters,Use the + and - ( ) keys to change the parameter value.Press the key to confirm the setting: The display shows MEM.Press the key to cancel a modification and retain the previous value : Thedisplay shows ESC.

(1) To activate the antilegionella function, programme the F16 parameter to a value of between 55 and 67°C. When the function is enabled, the boiler's electronics system heats the water in the tank to a temperature greater than the value of F16 once a week. The function is tripped only if the water has never exceeded the value of F16 in the previous 7 days.

Parameter descriptionsFactory setting

MS 24 BIC FF MS 24 BIC

F01Boiler type10 = Leak proof box20 = Atmospheric gas burner

10 20

F02 Gas type02 = Natural gas and Propane (with corresponding diaphragm) 02

F03 Hydraulic system (Do not modify) 15

F04 Parameter setting programmable relay 1 (Do not modify) 04

F05 Parameter setting programmable relay 2 (DHW load pump) 03

F06 Setting the maximum set point temperature (°C) 00 = 85°C - 01 = 45°C (Do not modify) 00

F07 Inlet configuarion for domestic hot water priority : 00= Flow switch - Turbine flux Meter BITRON01= Flow switch - Turbine flux Meter FUGAS02= Not used

00

F08 Maximum boiler output during heating (0-100%) 100

F09 Maximum boiler output in DHW (0-100%) 100

F10 Minimum heating output (0-100%) 00

F11 Waiting time before another ignition (00-10 minutes) - 00 = 10 seconds 03

F12 Troubleshooting: Last error which occured. see : Description of error codes. --

F13 Factory data - Do not modify 00



F16 Antilegionella function (With F03=03) 00 = Antilegionella function not activated (1)55...67 = Antilegionella function activated (Set temperature °C)

00

F17 Selection heating pressure switch type: 00 = hydraulic pressure switch, 01 = Differential hydraulic pressure switch 00

F18 Factory data 00

É

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8. Commissioning

8.1 Commissioning procedure

Turn the boiler on. The display briefly shows the verion of the regulator programand then OFF (OFF position).Open the main gas supplyOpen the gas valve on the boilerPress the key to choose one of the 4 positions: Summer ( ), Winter ( ),Heating only ( ) or Stop.- Stop (Display: OFF) / Antifreeze protection active- DHW heating only: Only domestic hot water production is ensured, the

heating is switched off.(Display: Heating flow temperature + )

- Heating only(Display: Heating flow temperature + )

- Heating and domestic hot water(Display: Heating flow temperature + + )

The boiler starts up: The main burner ignites and the symbol is displayed onthe screen.In Summer position ( ), the main burner is ignited only if there is a DHW demand.Set the set point temperatures for the heating and the domestic hot water with the + / - ( ) and + / - ( ) keys.Heating: factory setting 85 °C. When setting the heating temperature, the symbol flashes and the display shows the set point temperature for theheating(°C).DHW: factory setting 85 °C. Recommended setting: 50 °C.When setting the DHW temperature, the symbol flashes and the display shows the domestic hot water set pointtemperature (°C).

8.2 The boiler does not start upOn initial commissioning, as long as any air in the gas pipes has not been eliminated, the burner may fail to ignite immediatelyand bring about the safety lockout of the system (E01 fault). If this happens, repeat the ignition procedure until the gas supplystabilises. Reset by pressing the key for at least 2 seconds.

No information is shown on the display. - Check the mains supply voltage- Check the fuses- Check the connection of the power cordIf there is a problem, the error is displayed on the screen.

See section 4.

8.3 In the event of run-off noiseVent the air in the heating systemIf noises caused by flow in the system can be heard: First of all, vent the heating system.

See section 5, chapter 7.3.

The first start-up is to be performed by your installation/commissioning engineer.Before proceeding with commissioning, check the installation and its tightness:

See section 5, chapter 7

É

6

CONTROLS AND SETTINGS

3,8 k

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Contents

1. Information to be noted before contacting Technical Assistance . . . . . . . . . . . . . . . . . . . . 77

2. Accessing the boiler components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

3. Draining the boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

4. Maintenance - Boiler maintenaince to be scheduled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824.1 Burner, combustion chamber and ignition electrode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824.2 Cleaning the fan ( FF Versions) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 834.3 Cleaning the water filters and descaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 844.4 Checking the expansion vessel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 874.5 Checking the anode in the tank (MS 24 BIC...) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 874.6 Checking the safety valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 874.7 Checking the tightness of the flue gas evacuation and air inlet connections (FF Versions) . . . . . . . . . . . . . . . . . . . . . 884.8 Checking the hydraulic pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 884.9 Checking combustion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 884.10 Checking the domestic hot water tank (When the boiler is connected to a DHW tank) . . . . . . . . . . . . . . . . . . . . . . . . 89

5. Checking the components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925.1 Switching off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925.2 Testing the sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 925.3 Checking the flowmeter (For versions MI and BIC only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 965.4 Checking the safety thermostat (105°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975.5 Checking the ignition / ionization sensor electrode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 985.6 Checking the low water pressure switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995.7 Checking the gas valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1005.8 Checking the reversal valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1015.9 2-speed heating pump with automatic air vent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1025.10 DHW load pump (MS 24 BIC...) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1035.11 Checking the fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1035.12 Checking the downdraught thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1045.13 Air pressure switch control (FF versions only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1045.14 Replacing the main exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

6. Gas settings - Gas conversion procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1066.1 Propane conversion kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1066.2 Gas conversion procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

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1. Information to be noted before contacting TechnicalAssistance

Information on the appliance (to be found on the nameplate):Boiler modelGas typeSerial number

Other information to be noted: Information displayed when the boiler is switched on

Display Description

3.2 (For all models)The figure displayed corresponds to the version of the software (Brief display)

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2. Accessing the boiler components

Board access:

1. Remove the 2 the front panel holding screws.2. Remove the front panel.

MS 24... :3. Unscrew the screw holding the panel closed

(Right-hand side)4. Tilt the control panel to the left.

MS 24

MS 24 BIC:5. Unscrew the 2 holding screws on the top of

the panel.6. Tilt the control panel forwards

MS 24 BIC

MS 24...7. MS 24... : (all versions excepted BIC):

- Take out the 2 screws- Open the 6 plastic clips on the control panel.- Tilt the control panel cover to access the PCB.

8. MS 24 BIC:- Unscrew the 3 control panel cover holding screws, to access the PCB.

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3. Draining the boilerCaution: The water may still be hot.Switch off the boiler.Cut the gas supply to the boiler.Close the main water valve,If it is not necessary to drain the entire installation, close theboiler's isolating valves.

3.1 Boilers MS 24 (FF) - MS 24 MI (FF) - MS 24 MI VMCBoiler with hydraulic connection plate:

To drain the boiler with the valve located on the connection plate (optional), proceed as follows:- Close the boiler's stop cocks; - Open the drain valve located on the heating flow valve (5 mm spanner).- Drain the boiler; - Close the drain valve (5 mm spanner).

Boiler not fitted with hydraulic connection plate (All countries except France):

The boiler can be drained directly from the drain valve with pipe fitting, incorporated in the water unit: - On MS 24 MI, MS 24 MI VMC and MS 24 MI FF boilers, the valve with pipe fitting is located on the bottom,- On MS 24, MS 24 FF boilers, the drain valve can be found beside the pump. Proceed as follows:- Close the boiler's stop cocks (if fitted). - Open the drainage valve (using a male 8 mm hexagonal spanner)- Drain the boiler ; - Close the drain valve (using a male 8 mm hexagonal spanner).

H2O

21

G000141

MS 24 MI (FF) - MS 24 MI VMC MS 24 (FF)

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3.2 Boilers MS 24 BIC (FF)Boiler with hydraulic connection plate:

To drain the boiler with the valve located on the connection plate (optional), proceed as follows:- Close the boiler's stop cocks; - Open the drain valve located on the heating flow valve (5 mm spanner)- Drain the boiler; - Close the drain valve (5 mm spanner).

Boiler not fitted with hydraulic connection plate (All countries except France):

The boiler can be drained from the drain valve with pipe fitting, located in the bottom of the boiler: - Close the boiler's stop cocks; - Open the drainage valve (using a male 8 mm hexagonal spanner)- Drain the boiler; - Close the drain valve (using a male 8 mm hexagonal spanner).

6

Draining the domestic hot water tank (MS 24 BIC):

1. Close the main water inlet valve.2. Drain the domestic hot water circuit by opening a hot water tap.

The tank can be drained using the valve B at the water unit. 3. After draining the tank, close the valve on the connection plate.

G000394G000411

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4. Maintenance - Boiler maintenaince to be scheduledAn annual inspection is compulsory. If, on annual inspection, the combusted gas analysis is not in compliance, a combustionsetting must be carried out.

Before any operation, ensure that:- The mains supply is disconnected,- The gas supply is shut off,- The boiler is hydraulically isolated and drained (See section 5, chapter 7).

4.1 Burner, combustion chamber and ignition electrode

During inspection and maintenance operations, always replace all gaskets on the parts removed.1. Remove the front plate from the combustion chamber. Remove the burner drawer.

Check the state of the burner and its fastening.Clean the burner with a soft brushClean the combustion chamber Remove any impurities found in the combustion chamber with a vacuum cleaner

2. Check that there are no cracks and/or other tears on the surface of the dismantled burner. If this is the case, replace the burner.

3. Replace the seals.4. Check the condition of the electrode. Replace the ionization/ignition electrode in the following cases:

- Electrode worn.- Electrode or porcelain damaged (chips, cracks...) or dirty.

5. Check the position of the ignition and flame detection electrode (See following chapter: page 98)6. Reassembly: To reassemble correctly, take care to position the two tabs at the bottom of the front plate of the combustion

chamber correctly in the notches provided in the combustion chamber.

Screwdriver: Reference 96920151

Be careful when re-assembling ! (... FF Versions)

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4.2 Cleaning the fan ( FF Versions)

MS 24 FFDisconnect the electrical connections from the fanRemove the venturi. Remove the holding screw from the fan support plateClean the inside of the fan using a vacuum cleanerFit the unit together.

MS 24 BIC FFDisconnect the electrical connections from the fanRemove the venturi. Remove the 2 holding screws from the fan supportplateClean the inside of the fan using a vacuum cleanerFit the unit together.

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4.3 Cleaning the water filters and descalingBefore any operation, ensure that:- The mains supply is disconnected,- The gas supply is shut off,- The boiler is hydraulically isolated and drained (See section 6, chapter 3).

To drain the domestic hot water circuit:Close the main water inlet valve.BIC Versions: Drain the domestic hot water tankDrain the domestic hot water circuit by opening a hot water tap

Cleaning the filters and cartridges (MI... Versions )

The filters in the heating circuit and the domestic hot water circuit are housed in removable cartridges.Proceed carefully when dismantling the various parts of the water unit. Do not use pointed tools and do not exert excessive force to remove the holding clips.

DHW Filter (detail E): Remove the clip (1) and extract the cartridge (2) containing the DHW filter on the cold water inlet, taking care not to exert excessive force.Eliminate any impurities and deposits found on the filters. Put the filters back in place in the cartridge. .Heating cartridge / Reversal valve: - Detail G: Dismantle the reversal valve motor (2) held in place by the clip (1) and the valve body (3). Then rinse the valve body in clean water.- Detail F: Remove the clip (1) and extract the cartridge and the filter (2). Eliminate any impurities by rinsing the filter. Refit the filter (detail F) and the reversal valve (detail G)Also clean the housing of the DHW sensor (detail D): to do this, remove the clip (1) and dismantle the sensor (2).Bypass cartridge (detail H): Remove the clip (1) and extract the cartridge (2). Eliminate any impurities and deposits found on the cartridge.Fit the unit together.

When replacing and/or cleaning the O-rings in the hydraulic circuit, use only Molykote 111 and no other lubricant (Do not use petroleum or grease).

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Cleaning the filters and cartridges (BIC... Versions ).

Proceed carefully when dismantling the various parts of the water unit. Do not use pointed tools and do not exert excessive force to remove the holding clips.

Heating cartridge: To extract the heating filter cartridge:- Detail G: Dismantle the reversal valve motor (2) held in place by the clip (1),- Detail F: Remove the clip (1) and extract the cartridge and the filter (2), taking care not to exert excessive force. Eliminate any impurities and deposits found on the filters. Fit the unit together.

When replacing and/or cleaning the O-rings in the hydraulic circuit, use only Molykote 111 and no other lubricant (Do not use petroleum or grease).

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Descaling / Cleaning the plate exchanger (MI and BIC versions)Depending on the water quality and the operating mode, limescale deposits may form in the drinking water circuit side of the plate exchanger. Periodic descaling may therefore be necessary.

To clean the exchanger and/or the drinking water circuit, we recommend using Cillit FFW-AL or Benckiser HF-AL.

1. To dismantle the domestic hot water exchanger:Unscrew the connection pipe from the expansion vessel at the water unit,Remove the heating pressure switch (detail H), without disconnecting the wiring; Remove the two holding screws H from the water/water exchanger, which can be seen from the front, and extract the exchanger from its housing

2. Clean the plate exchanger and then put it back in place, after replacing the 4 gaskets3. Tighten the expansion vessel connection pipe at the water unit4. Put the hydraulic pressure switch back in place in its housing (Detail H).

Caution: Proceed carefully when dismantling the various parts of the water unit. Do not use pointed tools and do not exert excessive force to remove the holding clips.

G000465

Replace the 4 gaskets !

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4.4 Checking the expansion vesselCheck the expansion vessel and replace it if necessary. See section 5, chapter 2.7 Connecting the expansion vessel.Version MS... BIC: Check also the DHW expansion vessel.If the transfer capacity is noticably low (temperature too low and/or flow rate less than 6.2 l/min), clean the plate exchanger(domestic hot water side) and the water filter cartridge.

4.5 Checking the anode in the tank (MS 24 BIC...)

4.6 Checking the safety valve

1 Heating: 3-bar safety valve2 DHW (BIC Versions): 7-bar safety valve.

Check whether there is any water in the end of the flow pipe on the safety valve.If any leaks are detected, replace the safety valve.

Check the magnesium anode every year and replace it if need be:Close the cold water inletDrain the domestic hot water tank (See section 6, chapter 3.2)Dismantle the anode A by undoing the nut at its base using a flat, 27 mm spanner.If dismantling the hatch cover B, replace the gasket.

MS 24 (MI) (FF) MS 24 BIC (FF))

11 2

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4.7 Checking the tightness of the flue gas evacuation and air inletconnections (FF Versions)

The connection pipes must be serviced at least once a year.Check the tightness of the flue gases evacuation and air inlet connections. Check the concentric flue gas evacuation and combustive air inlet pipes.Check that the pipe and the terminal are empty along their entire length. On concentric flue gas discharge systems (forced flue), the C02 level in the annular space in the measurement piping can also be checked. The flue gas discharge system is considered leak-proof if the measured CO2 level is lower than 0.2% (When the boiler operates at maximum output).

4.8 Checking the hydraulic pressureThe hydraulic pressure must reach a minimum of 0.7 bar.

If necessary, top up the water level in the heating system (recommended hydraulic pressure between 0.7 and 1.5 bar).

4.9 Checking combustionMS 24 ... FF Versions:

The boiler is fitted with two specific outlets. One outlet is connected to the flue gas evacuation circuit and is used to check thecombustion products characteristics and the combustion efficiency. The other outlet is connected to the combustive air intakecircuit and is used to check whether any combustion products are put back into circulation in the coaxial ducts. In the outlet connected to the evacuation circuit, the following parameters can be checked• Temperature of the combustion products• Concentration of oxygen (O2) • Concentration of carbon dioxide (CO2) • Concentration of carbon monoxide (CO). The temperature of the combustive air must be taken by inserting a sensor to a depth of at least 3 cm inside the outlet.

If the analysis of the flue gases does not comply, review the settings of the boiler and the installation (Connection to the flue gas pipe, Gas settings, Ventilation)

MS 24 Versions (all versions excepted FF): Measure the concentration of carbon monoxide (CO) in the ambient air 50 cm from the front panel of the boiler for at least 30seconds.The maximum CO content in the ambient air is 20 ppm.

If a higher value is measured, review the settings of the boiler and the installation (Connection to the flue gas pipe, Gas settings, Ventilation).

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4.10 Checking the domestic hot water tank (When the boiler is connectedto a DHW tank)

4.10.1 Components to be checked

Magnesium anodeThe magnesium anode must be checked at least every 2 years. After the first check, determine the frequency of future checks onthe basis of anode wear. The anode can be checked by one of the two methods below:

• Inspection:Open the domestic hot water tank: the anode must be replaced if its diameter is less than 15 mm (original diameter = 33 mm).

• Checking by electrical measurement:Remove the coverdisconnect the earth wire from the anodemeasure the strength of the current between the tank and the anode. if the current is less than 0.1 µA, the anode must be replaced.

DHW tank and exchangerIn hard water regions, we recommend the annual descaling of the DHW tank in order to maintain its performance. The first checkis usually done after 2 years at the same time as the visual check on the magnesium anode when the DHW tank is open.The periodicity of the following checks will be defined according to the scaling noted.

• Descaling the exchangerDescale the exchanger in order to maintain its performance levels.

• Descaling the DHW tankRemove limescale deposits in the form of sludge or strips in the bottom of the tank (If necessary, remove the DHW tank or use a water vaccum cleaner for floor-standing tanks located under the boiler). On the other hand, do not touch limescale adhering to the walls of the tank as it provides effective protection against corrosion and improves the insulation of the DHW tank.

Safety valve or safety unitThe safety valve or unit must be operated at least once a month to ensure proper operating and to prevent from any overpressurewhich may damage the DHW tank.

CasingThe tank casing can be cleaned with a soft cloth and soapy water.

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4.10.2 Opening the SR 130 tank for maintenance

Use a new leak tight seal on the inspection trap,Turn off the domestic cold water inlet,Open the hot water taps to drop the pressure and drain the pipes to the DHW tank.

• Removing the anodeRemove the cover A using a broad-bladed screwdriver (see detail) and then remove the insulation,Remove the sensor B from its sensor tube,Remove the trap C (13 mm spanner).

• Check the condition of the anode and replace it if necessary. Check the extent of scaling in the tank and on the exchanger.

• ReassemblyTo re-assemble, perform the above actions in reverse order,Replace the leakproof seal E on the trap. Position the gasket with the retainer ring F, taking care to place the positioning lug on the gasket to the outside of the DHW tank and the retainer ring,Engage the B DHW sensor fully in the sensor tube.

• Filling and tightness checkOpen the cold water inlet,Fill the tank,Bleed the tank using the hot water taps,Close all hot water taps when the water flows normally and no more air is being flushed out,Restart the boiler,Heat the DHW tank to the operating temperature,Check the tightness of the flange on the DHW tank,Put the cover A back in place.

The operations described below shall only be performed with the boiler and power supply off.Only original spare parts must be used.Maintenance operations must be done by a qualified engineer.

The flange mounting bolts must not be excessivelytight: 8 N·m ± 1. Use a dynamometric spanner. Note: An approximate torque of 8 N·m is obtainedby hand-tightening the nut and adding ¼ of a turnwith a spanner.

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4.10.3 Opening the BMR 80 tank for maintenance

Have a lip gasket and a retainer ring on hand for the inspection trap,Turn off the domestic cold water inlet,Open a hot water tapOpen the valve on the safety unitLift the insulation Pull out the DHW sensor (A)Remove the inspection trap (13 mm spanner) Drain the domestic hot water tank.Check the condition of the anode C. Replace if necessary.Check the extent of scaling in the tank and on the exchanger. Remove limescale deposits in the form of sludge or strips in the bottom of the tank. On the other hand, do not touch limescale adhering to the walls of the tank as it provides effective protection against corrosion and improves the insulation of the DHW calorifier.Replace the D lip gasket + E retainer ring. Place the positioning lug on the gasket toward the outside of the tank.

Each time it is opened, the lip gasket + retainer ring unit must be replaced to guarantee tightness.

Then replace all the parts in reverse order.

The screws retaining the visit trap must be tightened to 6 N·m +1/-0. Use a dynamometric spanner. Approximately 6 N·m is obtained by manipulating the box spanner with the small lever and 15 N·m by manipulating it with the large lever.

• Filling and tightness checkOpen the cold water inlet,Fill the tank,Bleed the tank using the hot water taps,Close all hot water taps when the water flows normally and no more air is being flushed out,Restart the boiler,Heat the DHW tank to the operating temperature,Check the tightness of the flange on the DHW tank.

The operations described below shall only be performed with the boiler and power supply off.Only original spare parts must be used.Maintenance operations must be done by a qualified engineer.

C0

03

38

6-B

91

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5. Checking the components

5.1 Switching off

5.2 Testing the sensors

5.2.1 Ohmic values of the sensorsThe temperature/resistance correlation is shown below.

* Optional with independent DHW tank

Before any operation, ensure that:- The mains supply is disconnected,- The gas supply is shut off.Wait until the boiler cools down

- Domestic hot water sensor (AD250)*

- Boiler sensor (CTN)

- DHW sensor (CTN)

- Outside sensor (HX31)

G000462

CTN sensor, 10 kohm at 25°C CTN sensor, 10 kohm at 25°C0 °C 32014 Ω -20 °C 96124 Ω 35 °C 6536 Ω

10 °C 19691 Ω -15 °C 72334 Ω 40 °C 5332 Ω

20 °C 12474 Ω -10 °C 54931 Ω 45 °C 4374 Ω

25 °C 10000 Ω -5 °C 42080 Ω 50 °C 3607 Ω

30 °C 8080 Ω 0 °C 32504 Ω 55 °C 2990 Ω

40 °C 5372 Ω 5 °C 25307 Ω 60 °C 2491 Ω

50 °C 3661 Ω 10 °C 19853 Ω 65 °C 2085 Ω

60 °C 2535 Ω 15 °C 15688 Ω 70 °C 1753 Ω

70 °C 1794 Ω 20 °C 12483 Ω 75 °C 1481 Ω

80 °C 1290 Ω 25 °C 10000 Ω 80 °C 1256 Ω

90 °C 941 Ω 30 °C 8060 Ω 85 °C 1070 Ω

G000491

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5.2.2 Boiler sensor (CTN)

MS 24 BIC (FF)

MS 24 (FF) - MS 24 MI (FF / VMC)

Disconnect the sensor wires,Measure the resistance on the sensor terminals. If the value measured by the ohmmeter does not match the one in the table, replace the sensor.

Refer to the table of ohmic values of the sensors: page 92.

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5.2.3 Domestic hot water sensor CTN (MS 24 MI ...)

5.2.4 Tank sensor CTN (MS 24 BIC - MS 24 BIC FF)

Disconnect the sensor to check its ohmic value.Measure the resistance on the sensor terminals. If the value measured by the ohmmeter does not match the one in the table, replace the sensor.


Disconnect the sensor to check its ohmic valueIf the value measured by the ohmmeter does not match the one in the table, replace the sensor.


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5.2.5 Outside sensor (Option package HX31) Measurement of the ohmic value:

Disconnect the outside temperature sensor connected from the control panel (two RED cables). Measure the resistance on the sensor terminals: If the values measured on the ohmmeter do not correspond to those in the table, replace the sensor.Refer to the table of ohmic values of the sensors: page 92.

Heating curve setting:The +/- keys are used to modify the heating curve kt .

For a housing unit with average insulation fitted with a heatingsystem using radiators, set the heating curve kt to a value of 25.

TM = Boiler temperatureTE = Outside temperature

MS 24 (FF) - MS 24 MI (FF/VMC) MS 24 BIC (FF)

Connecting theoutside sensor

PCB

Connecting the outside sensor Connecting the outside sensor

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5.3 Checking the flowmeter (For versions MI and BIC only)

See electrical diagram in section 7.

To check the flow switch :Open a hot water tapPress button for 5 seconds, Press the (+/-) keys next to to display the parameter A08:A08 = Domestic hot water flow(l/min x 10)If the measured flow rate does not match to the actual flow rate, the flowmeter is defective.The mains supply to the flowmeter can also be measured on the PCB: 5 VDC

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5.4 Checking the safety thermostat (105°C)


MS 24 (FF) - MS 24 MI (FF/VMC) MS 24 BIC (FF)

Allow the boiler to cool down.Disconnect the two terminal pinsConnect the ohmmeter to the thermostat terminalsThe resistance should be equal to zero ohms (Normally closed contact)Otherwise, the safety thermostat is defective

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5.5 Checking the ignition / ionization sensor electrodeThe ignition electrode also acts as the ionization sensor.

To check or replace the ignition electrode:Disconnect the ignition electrode cable,Remove the front plate from the combustion chamber (4screws).MS 24 BIC (FF): Unscrew the connection under theburner drawer - 30 spanner,Remove the burner drawer (4 screws): Use the specialscrewdriver, reference 969 20 151.Unscrew the screw holding the electrode in place,Check the good general appearance (particularly, nochips, cracks, dirt on the porcelain) and the state ofwear of the electrode.Replace the electrode protection if necessary.Replace the ionization/ignition electrode in the followingcases:

- Electrode worn - Electrode or porcelain damaged (chips, cracks...)

or dirtyIf replacement is necessary, proceed as follows:

- Install the new electrode with a new protection. - Check the positioning of the electrode (gap: 3 mm)- To re-assemble, proceed in reverse order.


MS 24 BIC (FF):

All versions:

Position of the electrode:

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5.6 Checking the low water pressure switch If an extra pump is used on the heating system, it must be fitted to the boiler's return circuit in order that the hydraulic pressureswitch can operate correctly.

Low water pressure switch: MS 24 MI... - MS 24 BIC

Measure the ohmic value on the pressure switch terminalsContact open (infinite resistance): pressure less than or equal to 0.45 +/- 0.15 barContact closed (zero resistance): pressure more than 0.45 bar

Water diaphragm pressure switch.Normally open contact (N.O.)Manufacturer: BITRONModel: SIOMaximum admissible current: 10A / 250 V ACMax operating pressure: 4 barMax. admissible temperature: 90°C.


Low water pressure switch: MS 24 - MS 24 FF

Measure the ohmic value on the pressure switch terminalsContact open (infinite resistance): pressure less than or equal to 0.45 +/- 0.15 barContact closed (zero resistance): pressure more than 0.45 bar

Normally open contact (N.O.)Maximum admissible current: 10A / 250 V AC


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5.7 Checking the gas valve

Checking the gas valveConnect the manometerCheck the drop in pressure upstream when opening the gas valve.

Replacing the gas valve

Before any operation, ensure that:- The mains supply is disconnected,- The gas supply is shut off.

Specifications:- Type: SIT SIGMA 845048- Electric coils connected in parallel- Electricity supply: 230 V- Maximum admissible pressure on the gas valve: 60 mbar- Mains supply to the modulator: 42 - 310 mA DC

Check the ohmic value of the valveDisconnect the connectors:

Resistance on the electric modulator terminals:20 Ohm (at 25°C)

- Check the coil on the gas valveTerminals 1 - 3: 6,5 kohmTerminals 1 - 4: 7,4 kohm

If the ohmmeter measurement is infinite, this shows a deteriorationof the gas valve. M: Output modulator

Before any operation, ensure that:- The mains supply is disconnected,- The gas supply is shut off.

1. Close the main gas inlet valve2. Close the gas valve of the boiler.3. Cut the power supply to the boiler.4. Disconnect the connectors5. MS 24 BIC : Unscrew the fittings on the gas valve.

MS 24 (MI)... : Dismantle the top and bottom flanges, each held in place by 2 screws (Allen key 4 mm).6. Install the new gas valve with the new gaskets and connect the wiring harness.

Caution: Put the diaphragm back in place - See section 6, chapter 6.2.7. Check the leak tightness of the connections.8. Check the settings according to the gas type: See section 6, chapter 6.2.

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5.8 Checking the reversal valveMS 24 MI ... and MS 24 BIC

To check switching of the reversal valve:- Pull the pin 1 securing the valve motor to the right, and then until it stops, - Pull the valve motor 2 to extract it from its housing- To create a DHW demand, open a hot water tap or increase the DHW set point temperature.- The axis 3 in the valve motor moves to the forward position (switch to DHW mode position)- Otherwise, the valve motor axis stays in heating position and does not switch

Also check the wiring harness and the mains supply on the reversal valve.

G000418

: Valve motor axis in DHW position

: Valve motor axis in heating position

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6

5.9 2-speed heating pump with automatic air ventHigh manometric height pump suitable for the majority of heating systems.The automatic air vent incorporated in the pump enables quick venting of the heating system.

Disconnect the pump connectorCheck for the presence of the 230 V power supply on the connector terminals.See electrical diagram in section 7.

Automatic air vent

Pump GRUNDFOS UPSO 15-50

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5.10 DHW load pump (MS 24 BIC...)

5.11 Checking the fan

Pump GRUNDFOS UPSO 15-60 CIL2

Disconnect the pump connectorCheck for the presence of the 230 V power supply on the connector terminals

Disconnect the electrical connections from the fan (Red wire - Blue wire).Measure the ohmic value on the fan terminals : the resistance should be between 38 and 48 Ohm (at 20°C)The presence of the 230 V power supply can be checked between the red and blue wires on the fan.

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5.12 Checking the downdraught thermostat


5.13 Air pressure switch control (FF versions only)

Downdraught thermostat (Klixon type)(all versions excepted ... FF ):MS 24 (MI): The flue gas thermostat shuts down the boiler if theflue gas temperature reaches 70 °C.MS 24 MI VMC: The flue gas thermostat shuts down the boiler ifthe flue gas temperature reaches 57 °C.The flue gas thermostat resets automatically.The code E03 appears.

Disconnect the electrical wires. Measure the ohmic value on the flue gas thermostatterminals:

- At room temperature, the thermostat should be on-state.- If resistance infinite: Thermostat defective (when cold) or

flue gas thermostat has tripped (if the temperature ishigher than or equal to 70°C).

Switch off the mains supplyDisconnect the pressure switch wiresMeasure the ohmic value on the pressure switch terminals:

- Check on standby: If there is no pressure, the resistance is infinite.- Functional control: Blowing into the pipe causes the air pressure switch

contact to close (you will hear a click). When the contact is closed, theresistance on the pressure switch terminals is 0 Ohm.

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5.14 Replacing the main exchangerTo do this, proceed as follows:

Switch off the mains supplyDrain the boiler.Remove the front panelDisconnect the ignition electrode cable,Remove the front plate from the combustion chamber(4 screws).Remove the burner drawer (4 screws): Use the special screwdriver, reference 969 20 151.Remove the pin on either side of the main exchanger.

Reassembly: To reassemble correctly, take care toposition the two tabs at the bottom of the front plate ofthe combustion chamber correctly in the notchesprovided in the combustion chamber.


Be careful when re-assembling ! (... FF Versions ).

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6. Gas settings - Gas conversion procedure

The boilers are set for natural gas (G20, G25) and can be converted to run on propane (G31).

6.1 Propane conversion kit

6.2 Gas conversion procedure1. Replacing the nozzles:

Use the special screwdriver, reference 96920151(Available in the spare part centre) .

Nozzles:

* Except VMC model

Only a qualified engineer may carry out the following operations.

Propane conversion kitfor MS 24, MS 24 FF, MS 24 MI, MS 24 MI FF : Package HX28 Reference 100016410for MS 24 BIC, MS 24 BIC FF : Package HX29 Reference 100016412

)

- Open the casing (MS 24 FF...)- Remove the combustion chamber plate- Carefully remove the burner drawer to access the nozzles.- Replace all nozzles (see the nozzle diameter according to gas

type in the table below). - Screw the nozzles in tightly to prevent gas leaks.- Reassembly: To reassemble correctly, take care to position

the two tabs at the bottom of the front plate of the combustionchamber correctly in the notches provided in the combustionchamber.

Boiler type MS 24 FF - MS 24 MI FF MS 24, MS 24 MI - MS 24 MI VMCGas type G20 G25 G31 G20 G25 G31*

Nozzle diameter (mm) 1.28 1.28 0.77 1.18 1.18 0.77Number of nozzles 13 13 13 13 13 13

Boiler type MS 24 BIC FF MS 24 BICGas type G20 G25 G31 G20 G25 G31

Nozzle diameter(mm) 1.18 1.18 0.69 1.18 1.18 0.69Number of nozzles 18 18 18 18 18 18

MS_Q

0004

Be careful when re-assem

7

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6

2. Diaphragm:

Diaphragms

* MS 24 MI VMC : No operation on propane

3. Setting of parameter F02MS 24 (FF) - MS 24 MI (FF) : For operation on propane, set parameter F02 to 01For operation on natural gas (H or L), set parameter F02 to 02MS 24 MI VMC: No operation on propane.For operation on natural gas (H or L): It is not necessary to modify parameter F02.MS 24 BIC (FF): It is not necessary to modify parameter F02.

4. Adjusting the gas valve

To set or check the nozzle pressure according to gas type, refer to the values shown in the tables below andproceed as follows:

For operation with propane: MS 24 (FF), MS 24 MI (FF):- Remove the diaphragm located in the gas valve

unit. MS 24 BIC (FF):- Install the diaphragm for operation on propane

(See table below)

Boiler type MS 24 FF - MS 24 MI FF MS 24, MS 24 MI - MS 24 MI VMC

Gas type G20 G25 G31 G20 G25 G31*

Internal diameter of the diaphragm (mm) 4.8 4.8 - 5.5 5.5 -

Boiler type MS 24 BIC FF MS 24 BIC

Gas type G20 G25 G31 G20 G25 G31

Internal diameter of the diaphragm (mm) 4.2 4.2 3.5 4.2 4.2 3.5

Diaphragm

MS 24 (FF), MS 24 MI (FF) MS 24 BIC (FF)

Diaphragm

MS 24 (FF), MS 24 MI (FF) MS 24 BIC (FF)

G000389

a

b

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Gas pressure settings table:

* Except VMC model

Measuring the pressure: Connect the positive pressure outlet from a differential pressure gauge, preferably a water pressure gauge, to the pressure outlet (Pb) on the gas connection . For FF versions (Forced flue versions): Connect the negative outlet from the pressure gauge to a specific T-connection used to interconnect the boiler's pressure balancing outlet, the gas valve's pressure balancing outlet (Pc) and the pressure gauge itself. An equivalent measurement can be taken by connecting the pressure gauge to the pressure outlet (Pb), without the front panel of the sealed chamber; A measurement of the nozzle pressure taken without following the method described may be distorted owing to the fact that it did not take into account the vacuum created by the fan in the sealed chamber.

Setting method 1: Operation at max and min output can be directly controlled from the boiler's control panel by proceeding as follows:Press the + + keys simultaneously for approximately 6 seconds.The symbols and flashThe screen alternately displays 100 and the boiler temperature:The boiler runs at maximum output: 100 % To instantly modify the boiler's heating output from 0 % to 100 % or vice versa, press the + and - ( ) keys,To gradually modify the boiler's heating output (in intervals of 1 %), press the + and - ( ) keys.Turn the screw (a) to obtain the pressure shown at maximum output:Turn the screw (a) clockwise to inrease the nozzle pressure or anti-clockwise to reduce it.Turn the screw (b) to obtain the pressure shown at minimum output:Turn the screw (b) anti-clockwise to increase the nozzle pressure or clockwise to reduce it.To exit this function, press the keyMeasure the boiler's gas supply pressure at the pressure outlet (Pa) on the gas valve: 37 mbar for propane, 20 mbar for natural gas G20 or 25 mbar for natural gas G25. Make a note on the boiler's rating plate of the gas type and the setting made.

Setting method 2:

• Setting to nominal output:Open the gas inlet valve; Press the key and select the winter position ( + ) by successively pressing it.Open the drinking water draw-off tap so as to obtain a flow rate of at least 10 litres per minute or ensure that there is actually a demand for maximum heat; Remove the modulator cover; Adjust the brass screw (a) until you obtain the pressure shown in the table below; Measure the boiler's gas supply pressure at the pressure outlet (Pa) on the gas valve: 37 mbar for propane, 20 mbar for natural gas G20 or 25 mbar for natural gas G25.

Boiler type MS 24 FF - MS 24 MI FF MS 24, MS 24 MI - MS 24 MI VMCGas type G20 G25 G31 G20 G25 G31*

Pressure at reduced output (mbar) 2.0 2.6 5.7 2.4 3.1 5.6Gas pressure at nominal output (mbar) 11.6 14.2 32.6 13.8 16.6 31.0

Boiler type MS 24 BIC FF MS 24 BICGas type G20 G25 G31 G20 G25 G31

Pressure at reduced output (mbar) 1.7 2.1 6.9 1.6 2.1 6.6Gas pressure at nominal output (mbar) 7.8 9.5 24.7 7.5 9.2 18.1

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• Setting to reduced output: Disconnect the power cable on the valve modulator and unscrew the red screw (b) until you reach the pressure value that corresponds to reduced output (See table below); Reconnect the cable; Put the cover back on the modulator and tighten the holding screw.

5. Final checks

Make a note on the boiler's rating plate of the gas type and the setting made.

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ELECTRICAL DIAGRAMS

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Contents

1. Electrical diagram - MS 24 MI FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

2. Electrical diagram - MS 24 MI - MS 24 MI VMC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

3. Electrical diagram - MS 24 FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

4. Electrical diagram - MS 24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

5. Electrical diagram - MS 24 BIC FF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

6. Electrical diagram - MS 24 BIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

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1. Electrical diagram - MS 24 MI FF

230 V main supply Low water pressure switchIgnition/ionization electrode Safety thermostatReversal valve Boiler sensor (CTN)Boiler pump Outside sensor (Option)Gas valve Air pressure switchFanFlowmeterCTN domestic hot water sensor

Colour of the wires:

C Sky blueM BrownN BlackR Red

G/V Green / YellowB WhiteV Green

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2. Electrical diagram - MS 24 MI - MS 24 MI VMC

230 V main supply Low water pressure switchIgnition/ionization electrode Safety thermostatReversal valve Boiler sensor (CTN)Boiler pump Outside sensor (Option)Gas valve Flue gas thermostatFlowmeterCTN domestic hot water sensor




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3. Electrical diagram - MS 24 FF

230 V main supply Low water pressure switchIgnition/ionization electrode Safety thermostatReversal valve Boiler sensor (CTN)Boiler pump Outside sensor (Option)Gas valve Air pressure switchFan




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7

4. Electrical diagram - MS 24

230 V main supply Safety thermostatIgnition/ionization electrode Boiler sensor (CTN)Reversal valve Outside sensor (Option)Boiler pump Flue gas thermostatGas valveLow water pressure switch




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5. Electrical diagram - MS 24 BIC FF

230V

main

supp

lyIgn

ition/i

oniza

tion e

lectro

deRe

versa

l valv

eBo

iler p

ump

Gas v

alve

Fan

Flowm

eter

CTN

dome

stic h

ot wa

ter se

nsor

Low

water

pres

sure

switc

hSa

fety t

herm

ostat

Boile

r sen

sor (

CTN)

Outsi

de se

nsor

(Opti

on)

Air p

ress

ure s

witch

DHW

load

pump

Contr

ol re

lay

Colo

ur o

f the

wire

s:

CSk

y blue

MBr

own

NBl

ack

RRe

dG/

VGr

een /

Yell

owB

Whit

eV

Gre

en

117

7

6. Electrical diagram - MS 24 BIC

230V

main

supp

lyIgn

ition/i

oniza

tion e

lectro

deRe

versa

l valv

eBo

iler p

ump

Gas v

alve

Flowm

eter

CTN

dome

stic h

ot wa

ter se

nsor

Low

water

pres

sure

switc

hSa

fety t

herm

ostat

Boile

r sen

sor (

CTN)

Outsi

de se

nsor

Flue g

as th

ermo

stat

DHW

load

pump

Contr

ol re

lay

Colo

ur o

f the

wire

s:

CSk

y blue

MBr

own

NBl

ack

RRe

dG/

VGr

een /

Yell

owB

Whit

eV

Gre

en

118

7

119

© CopyrightIn the interest of customers, DE DIETRICH THERMIQUE are continuously endeavouring to make improvements in product quality. All thespecifications stated in this document are therefore subject to change without notice.

DE DIETRICH THERMIQUE BP30 57 Rue de la Gare F-67580 MERTZWILLERTel.: (+33) 3 88 80 27 00 Fax: (+33) 3 88 80 27 99

www.dedietrich-heating.com

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