sab 193, 233, 283 atex screw compressor...

Op

erating

man

ual

SAB 193, 233, 283 ATEXScrew compressor units

en

Manual for SAB 193, 233 and 283 screw compressors

Unit no.

Compressor 193 233 283

Compressor type S L E X

Refrigerant R717 HFC/HCFC ____ Other: _________

Oil typeOil type: __________________ . Evap. temp. _______ . Cond. temp. _______

Control Unisab II Unisab III None Other

Oil filter Single Dual

Oil coolingRefrigerant cooled oil cooler Water cooled oil cooler

Liquid injection in compressor Single port Dual port

Discharge port Standard AC (Low Vi port)

Oil pump

Economizer system(ECO-system) Economizer connection Economizer type _________

Ex-execution (ATEX)

Supply voltage

Motor 3 x _________V / _________ Hz

Control 1 x _________V / ________ Hz

Heating elements (phasing)1 x _________V / ________ Hz

Motor

IP23 IP55

Power ________ kw Size IEC _________

Anti condensation heater

Max. rel. humidity = 85% (Std.) Max. rel. humidity = 100%

Approval PED (97/23/EC) Others ________

Coalescer element pcs.

Unisab setting valuesSeparator velocity ref. _______

Separator velocity ref. CR _______

ATEX Operating manual - SAB screw compr. 193-233-283002457 - en 2012.05. 1/63

Safety valve:Data for calculation ofdownstream line accord-ing to EN 13136

Vessel data

TypeExternal surface

[m2]Design pressure

[bar]

Condenser

Evaporator

Liquid separator

Oil separator

Oil cooler

Economizer

Other

Pressure loss, if any, from safety valve to customer connection

(based on design pressure, [bar] _____________

Safety valve type:

Back pressure dependent Back pressure independent

Contents

1. Introduction to ATEX operating manual 5

1.1.2 Safety precautions definitions used in this manual 7

2. Areas of application of screw compressor

unit 8

2.1.1 Application 8

2.1.2 Application of combustion engines 8

3. Identification 9

3.1.1 Unit/pipe system name plate 9

3.1.2 Compressor name plate Frick ATEX 11

3.1.3 Vessel name plate 13

4. Safety precautions 14

4.1.1 Signs 14

4.1.2 During operation 15

4.1.3 Maintenance safety/safety at servicing 17

4.1.4 Electrical installations 17

4.1.5 Lubricating oils 18

4.1.6 Purging a refrigeration plant 19

4.1.7 F-gas regulation (flourinated greenhouse gases) 19

5. Sound measurement and noise data 21

5.1.1 Noise data 21

5.1.2 Noise data for screw compressors 21

6. Installation 22

7. Operating instructions 23

7.1.1 Description of unit 23

7.1.2 Principle P&I diagram 25

7.1.3 Descriptions of main components and systems 30

7.1.4 Compressor 30

7.1.5 Compressor lubrication system 31

7.1.6 No pump oil system 31

7.1.7 Demand pump oil system 32

7.1.8 Compressor oil separation system 32

7.1.9 Automatic oil return valve 34

7.1.10 Cold-start system 36

7.1.11 Compressor hydraulic system 37


7.1.12 Volumizer volume ratio control 38

7.1.13 Compressor oil cooling systems 38

7.1.14 Suction check valve by-pass 40

7.1.15 Low ambient temperature operation 41

7.1.16 Start-up 42

7.1.17 Stopping routine 45

8. Troubleshooting 46

9. Maintenance instructions 50

9.1.1 Maintenance of compressor unit 50

9.1.2 Operations log 53

9.1.3 Oil 54

9.1.4 Motor 57

10. Final disposal 58

11. Appendices 59

11.1.1 Declaration of conformity 59

Index 62

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ATEX Operating manual - SAB screw compr. 193-233-283002457 - en 2012.05.

1. Introduction to ATEX operating manual

The screw compressor and the unit may be fitted with different equipment, depending ontheir functions and requirements. Part of this equipment is described in this manual althoughit may not be fitted on your particular unit.

1.1.1 The purpose of this manualThe purpose of this manual is to describe:

• Dangers resulting from failure to comply with safety precautions when operating theequipment and performing maintenance tasks.

• How to start, operate and stop the equipment safely.

• How to act when problems occur during operation.

• Scheduled maintenance tasks for the equipment and when/how to carry them outsafely.

• Identification of components with ATEX related specifications (EC directive 94/9/EC).

This manual is primarily intended for operators.

• It is important that the operating personnel familiarize themselves with the contentsof this manual in order to ensure proper and efficient operation. Johnson ControlsDenmark is not liable for damage occurring during the warranty period where this isattributable to incorrect operation.

This manual does not describe:

• Control systems. A specific operating manual is delivered with the compressor.

• Safety when handling refrigerants and oils.

• Installation.

• Service and repair including spare part lists.

For further information, see www.sabroe.com

Introduction to ATEX operating manual


This manual covers the following types of units:

EU designation US designation

RWF ІІ Model No.

SAB 193 S RWF 100

SAB 193 L RWF 134

SAB 233 S RWF 177

SAB 233 L RWF 222

SAB 233 E RWF 270

SAB 283 S RWF 316

SAB 283 L RWF 399

SAB 283 E RWF 480

SAB 283 X RWF 546

Both types of designation may occur in the description.

American standards are used in all P&I diagrams in this manual.

This manual is produced by:

Johnson Controls Denmark ApSChristian X's Vej 2018270 Højbjerg, DenmarkPhone +45 87 36 70 00Fax +45 87 36 70 05CVR No 19 05 61 71www.sabroe.com

Copyright © 2010 Johnson Controls Denmark ApS

This manual must not be copied without the written permission of Johnson Controls Denmarkand the contents must not be imparted to a third party nor be used for any unauthorized pur-poses. Contravention will be prosecuted.

The original version of this manual is the English language version. If there are any discrepan-cies or conflicts between the English and any other version that has been translated into an-other language, the English version will prevail.


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1.1.2 Safety precautions definitions used in this manual

Danger!

Indicates an imminently hazardous situation which, if not avoided, will result in death or seri-ous injury.

Warning!

Indicates a potentially hazardous situation or practice which, if not avoided, will result indeath or serious injury.

Caution!

Indicates a potentially hazardous situation or practice which, if not avoided, will result in dam-age to equipment and/or minor injury.

Note: Indicates an operating procedure, practice, etc. or portion thereof which is essential tohighlight.



2. Areas of application of screw compressor unit

2.1.1 ApplicationTo prevent unintentional application of the compressor which could injure personnel or dam-age equipment, the following must be observed:

• The compressor must only be used as a refrigeration compressor and within the oper-ating limits specified in the manuals or in a written agreement with Johnson ControlsDenmark.

• The compressor must only be used with the refrigerant(s) and number of revolutionsper minute, as shown on the compressor name plate. Other refrigerants must only beused in accordance with Johnson Controls Denmark's instructions. All other types ofgas must only be used with a written permission from Johnson Controls Denmark.

• Johnson Controls Denmark further accept no liability of any kind for damage to com-pressor unit and plant parts caused by torsional oscillation or the like which is attrib-utable to built-in VSD solutions initiated by the customer after delivery.

• The compressors are approved for application in potentially explosive atmospheres,provided they have been fitted with explosion-proof equipment. This can be seen fromthe Ex name plates fixed on each unit. Please note that specially made tools which donot cause any sparks must be used for all maintenance work on the compressor.

The compressor must NOT be used

• To evacuate the refrigeration plant of air and moisture.

• To put the refrigeration plant under air pressure in view of a pressure testing.

• As an air compressor

2.1.2 Application of combustion enginesIf combustion engines are installed in rooms containing refrigeration machinery or rooms withpipes and components containing refrigerant, make sure that in case of leakage, the air in-take for the engine comes from an area without refrigerant gas.

Failure to do so involves a risk of lubricating oil from the combustion engine mixing with re-frigerant. At worst this may lead to corrosion and damage the engine.

Warning!

Johnson Controls Denmark is not liable for injuries to personnel or damage to equipment re-sulting from using the equipment for other purposes than the ones stated above.

Areas of application of screw compressor unit

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3. Identification

3.1.1 Unit/pipe system name plate

BY JOHNSONCONTROLS

Scope

Design code

Approval No

Refrigerant

Supply voltage

Refrigerant charge

Pressure systemCategoryAllowable pressure

Test pressure

Allowable temp.

Refrigeration unit

Fluid

Type

No

Group

Control

Year

Max.

LP side HP side

V/Hz

kg

bar g

°Cbar g

2516-342

Min/Max.

The unit name plate is positioned on the frame and contains the following information:

Refrigeration unit No. Identification no. (serial no.)Year Year of manufacturing.Type Manufacturer's type designation.Scope For EC - PED approval: “Unit & Piping” means that the CE mark

covers the complete unit including the piping system.“Piping “ means that the CE mark covers the piping system onlyand it is the sole responsibility of the service engineer to ensureand declare that the complete unit is in conformity with theprovisions of all relevant directives. (See the CE Declaration ofconformity).

Design code Design code used for the unit and piping system.Approval no. If the unit/manufacture has been approved by a 3rd party/noti-

fied body.Refrigerant - Fluid Refrigerant of the unit.

Refrigerant designation (Rxxx) according to ISO 817.Refrigerant - Group For EC - PED approval:

Fluid group 1 or 2 according to PED directive.Supply voltage - Control Supply voltage and frequency of the control system.Refrigerant charge Weight of refrigerant charge of the unit.

Only stated if the unit includes an evaporator and/or a con-denser.

Pressure system Low pressure side of the unit piping is referred to as LP-side.High pressure side of the unit piping is referred to as HP-side.

Identification


Category For EC - PED approval:The maximum category of the piping system (CAT 1, 2 or 3.) orof the assembly unit and piping (CAT 3 or 4).

Allowable pressure, max. The max. pressure (pressure relative to atmospheric pressure)for which the unit/piping system has been designed in terms ofpressure strength design. Maximum practical operation pres-sure is lower than “maximum allowable pressure” depending onoperating conditions and the safety equipment settings.

Test pressure The test pressure with which the unit/piping system has beenstrength tested.

Allowable temperature,min./max.

Minimum and maximum temperatures for which the unit/pipingsystem has been designed.

CE xxxx The CE mark appears on the name plate for EC - PED approvalonly. The four digits compose the registration no. of the notifiedbody/3rd party in charge.

Ex An Ex mark appears on the name plate if the unit has beendesigned according to the EC – ATEX directive.

Note: Main supply voltage can be found on the motor and/or electrical panel name plate.

Identification

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3.1.2 Compressor name plate Frick ATEX

The compressor name plate is positioned on the compressor. The plate contains the followinginformation:

Model/serial no: Manufacturer's type designation and the compressor manufac-turing number.

Refrigerant: Shows which refrigerant is used.Volume ratio: Shows the volume ratio of the compressor.Max. driver speed: Shows the maximum number of revolutions permitted.Swept volume atmax. speed:

Shows maximum working pressure of compressor.

Max allowable pressure Shows maximum working pressure of compressor.Year of MFR: Year of manufacturing.

Ex. II 2 G T4

II: Equipment group: II indicates that the equipment is suitable for use in all areas, exceptfrom mines, liable to be endangered by explosive atmospheres.

2: Equipment category: 2 indicates that the equipment is suitable for use in areas in whichexplosive atmospheres are likely to occur

G: Character of hazardous environment: G indicates that the equipment is suitable for use inpotentially explosive gas, vapour and fog atmospheres.

T4: Temperature class: Indicates the surface temperatures which may occur on the compres-sor.

Identification


Screwcompr.

unit

Rotordia.mm

RotorL/D

Min.Speedrpm

Max.Speedrpm

Geometricalswept volumedrive shaft end

Ft3/Rev. M3/Rev.M3/H

2950 rpmSGC 1913 193 1.35 1,000 3,600 0.16653 0.004713 834SGC 1918 193 1.8 1,000 3,600 0.22204 0.006284 1,112SGC 2313 233 1.35 1,000 3,600 0.29301 0.008292 1,468SGC 2317 233 1.7 1,000 3,600 0.36897 0.010442 1,848SGC 2321 233 2.1 1,000 3,600 0.45580 0.012899 2,283SGC 2813 283 1.35 1,000 3,600 0.52501 0.014858 2,630SGC 2817 283 1.7 1,000 3,600 0.66115 0.018711 3,312SGC 2821 283 2.1 1,000 3,600 0.79546 0.022512 3,985SGC 2824 283 2.4 1,000 3,600 0.89858 0.025430 4,501SGCH/B 3511 355 1.1 1,000 3,600 0.82248 0.023276 4,120SGCH/B 3515 355 1.5 1,000 3,600 1.12154 0.031739 5,618SGCH/B 3519 355 1.9 1,000 3,600 1.42748 0.040398 7,150SGCB 3524 355 2.4 1,000 3,600 1.80328 0.051033 9,033Table 1: Geometrical swept volume

Identification

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3.1.3 Vessel name plate

The pressure vessel name plate is positioned on the shell of the vessel and contains the fol-lowing information:

Vessel no. Identification no. (serial no.)Year Year of manufacturing.Type Manufacturer's type designation.Design code Design code used for the pressure vessel.Approval no./CAT The approval no. of the vessel issued by the relevant 3rd party/

notified body.For EC - PED approval: CAT (Category 1, 2, 3 or 4) according toPED directives.

Side For heat exchangers only.Refers to the columns "Shell" side and "Tube" side of the heatexchanger.

Fluid Designation of the primary refrigerant(s) and the secondary re-frigerant(s).For EC - PED approval: Designation of the refrigerant(s) and/orthe highest fluid group (Group 1 or 2) according to PED direc-tive.

Allowable pressure, PS Min. and max. pressure (pressure relative to atmospheric pres-sure) for which the vessel or vessel part has been designed.

Allowable temperature,TS

Min. and max. temperatures for which the vessel or vessel parthas been designed.

Volume Volume of the vessel or vessel part.CE xxxx The CE mark appears on the name plate for EC - PED approval.

The four digits compose the registration no. of the notifiedbody/3rd party in charge.

Note: Depending on the supplier of the pressure vessel/heat exchanger the layout and con-tent of the name plate may differ from the Sabroe name plate above.

Identification


4. Safety precautions

4.1.1 SignsAll signs which may be found on your equipment are shown below. The number of signs, how-ever, may vary from one product to another.

Risk of electrical shockHigh voltage/

High pressure

High surface

temperature

(about 70°C)

The compressor may be

top-heavy

Internal overpressure Hazardous substance Cold surfacesDangerous noise level,

use hearing protectors

Do not step on surface No open flame Flammable gasThe unit IS filled with

refrigerant R290

Internal protection Pacemaker users keep out

Påfyldt beskytte lsesgasCharged with inert gasEnthält SchutzgasChargé du gaz prote cteu rContiene gas protector

N20,5 bar7.3 PSI

1534-169

Compressor blocks and units are

usually delivered without refrigerant

and oil. To protect the compressors

against internal corrosion, they are

delivered evacuated of all atmos-

pheric air and charged with dry

Nitrogen (N2) to an overpressure of

0.5 bar [7.3 PSI].

In such cases a yellow sign is affixed

to a visible spot on the compressor.

The magnetic field on the rotor

may affect pacemakers.

The motor rotor contains a powerful

magnetic field. This field may affect

digital devices such as watches,

mobile phones etc.

Assembly or maintenance of the

rotor must not be carried out by

people with pacemakers or any other

implanted medical electronic device.

The VSD contains capacitors capable

of storing electrical energy, ie there

is a risk of electrical shock within

15 minutes after the drive has been

turned off.

Safety precautions

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General

Use these precautions as a supplement to the safety precautions and warnings included in:

• All other manuals pertaining to the compressor/unit.

• Local, plant and shop safety rules and codes.

• National safety rules and regulations.

Read and understand all safety instructions before setting up, operating or servicing/perform-ing maintenance on the compressor. Assign only qualified personnel instructed in safety andall machine functions to operate or service this compressor.

Operators and maintenance personnel must carefully read, understand and fully comply withall warnings and instruction plates mounted on the machine.

• Observe the safety warnings on the compressor/unit.

• Use ear protection when operating the unit.

• Use safety equipment. Wear appropriate gloves as well as eye and face protectionwhen working with parts containing refrigerant and/or lubricating oil.

Note: These instructions only provide general information. The owner of the refrigerationplant is responsible for ensuring that all codes, regulations and industry standards are com-plied with.

4.1.2 During operation

Warning!

All safety features, disengagement and interlocks must be in place and function correctly be-fore the equipment is put in operation. Never by-pass or wire around any safety device.

Ventilation

Before operating the unit, always check the function of the ventilation system and refrigerantdetectors used in the area where the compressor unit is located (machine room).

Rotating parts

Warning!

Safety guards, shields, barriers, covers and protective devices must not be removed while thecompressor/unit is operating.

Vibration and noise

During operation, pay attention to the compressor unit process. Excessive vibration, unusualsounds etc. may indicate problems requiring your immediate attention.

Safety precautions


Pressure

Danger!

A compressor unit comprises a pressurized system. Never loosen threaded joints while thesystem is under pressure and never open pressurized system parts.

Note: Whenever a by-pass valve/safety valve has been activated we recommend recalibrat-ing it. This must be carried out by authorized personnel only. See also EN 378 and existingnational legislation.

Cooling water system

Warning!

The recirculation water system may contain chemicals or biological contaminants, including le-gionella, which can be harmful if inhaled or ingested. Water systems should only be operatedwith an effective biological treatment programme.

Safety precautions

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4.1.3 Maintenance safety/safety at servicing

• Personnel must be qualified according to national safety rules and regulations andperform the maintenance work according to EN 378.

• Read 4. Safety precautions before opening the compressor and other parts of the re-frigeration plant.

• It is recommended to remove all main fuses. Switch off all electric components on thecompressor/unit before starting the dismantling/servicing process and lock the mainswitch.

• Make sure that the motor cannot start up inadvertently.

• Make sure that there is no over-pressure and no refrigerant in the part to be disman-tled. Close all necessary stop valves.

• ATEX : In principle all parts should be electrically conductive to avoid sparking whenstatic electricity is build up.

• Materials should only contain a limited percentage of light metals.

• Use the prescribed tools and check that they are properly maintained and in goodworking condition. In explosion-proof areas, use tools suited for this specific purpose.

• The original parts delivered by Johnson Controls Denmark must not be changed withunspecified parts which are not ATEX approved.

• Use only Johnson Controls Denmark original spare parts; other parts may impair thesafety of the compressor/unit.

• Use gloves and protective goggles and make sure to have a gas mask close at hand.Also use electrical protection equipment and tools suited for electrical operation pur-poses.

Warning!

Use only oils with min. ignition temperature: 185°C

Warning!

Max. oil temperature for compressor: 65°C

4.1.4 Electrical installationsElectrical installations delivered with the compressor are in conformity with the ATEX direc-tive. If the installation is extended or additional equipment is mounted it must be in conformi-ty with the ATEX directive.

For equipment not delivered by Johnson Controls Denmark, it is the contractor who is respon-sible for the conformity with the provisions of the ATEX directive.

Especially, the contractor is responsible for equalizing potential differences on the compres-sor.

Safety precautions


Power supply

Danger!

HIGH VOLTAGE!

Before removing or opening any electrical enclosures, covers, plates, doors or working on anyelectrical circuits, place the main switch of the compressor/unit in the "OFF" position and lockit. Dismantle the main fuses to the compressor unit.

An electrician must analyse the electrical system to determine the possible use of power re-taining devices such as capacitors. Such power retaining devices must be disconnected, dis-charged or made safe before maintenance is performed.

4.1.5 Lubricating oilsCompressor oils include the following oil types:

Code design Oil typesM Mineral oil, naphtenic baseA Synthetic oils based on alkylated aromatics (alkyl-benzene)AP Synthetic oils blended from alkyl-benzene and poly-alfa-olefin base stocksS Semi synthetic oils (hydro-treated mineral oil on paraffinic base)

PAO Synthetic oils based on poly-alfa-olefinPOE Synthetic oils based on polyol estersPAG Synthetic oils based on polyalkylene glycols

See Sabroe oil recommendation for recommended type of oil.

Warning!

When charging oil, follow the safety instructions given by the oil supplier (MSDS: MaterialSafety Data Sheet). Always avoid direct contact with the oil as this may cause skin allergies.Always use protective equipment - goggles and gloves - when charging oil.

When changing oil on the compressor or draining oil from the vessel of the refrigeration plant,always collect the used oil in containers marked “waste oil” and send them to an approved in-cineration plant. It is not recommended to reuse oil.

Refrigerants

Be very careful when dealing with refrigerants. For safe handling please refer to the safetydata sheets etc. delivered by the refrigerant supplier.

Danger!

Pay close attention to the fact that large amounts of escaping (or released) refrigerant entailrisk of suffocation. Body contact with leaking liquid refrigerant entails high risk of injuriescaused by intense cold.

Safety precautions

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4.1.6 Purging a refrigeration plantPurging of air or other non-condensable gases is required in order to keep high system per-formance and avoid corrosion of the equipment which could endanger the safety of personsand equipment.

When purging a refrigeration system, make sure to observe the following:

• Refrigerants must not be released into the atmosphere except CO2, which can be re-leased slowly into the atmosphere.

• When purging an R717 system, use an approved air purger. The purged air must passthrough an open container or water for any remaining R717 to be absorbed. The wa-ter mixture must be sent to an authorized incineration plant.

• Halocarbon refrigerants (CFC, HCFC and HFC) cannot be absorbed by water. An ap-proved air purger must be fitted to the system. This must be checked regularly by useof a leak detector. All precautionary measures practicable must be taken to preventand minimise leakage of refrigerant from refrigeration and air conditioning systems tothe atmosphere.

Note: The occurrence of air is usually an indication of poor maintenance or lack of thorough-ness at installation.

Note: R717 systems should be purged on a regular basis to avoid atmospheric air and othernon-condensable gases.

4.1.7 F-gas regulation (flourinated greenhouse gases)Based on the Kyoto protocol regarding reduction of harmful gases in the atmosphere, the Eu-ropean Parliament (EU) has established guidelines for the regulation of certain greenhousegases in a directive named “F-gas regulation”. The following is an extract from the guidelineswhich is relevant for end users and operators.

Flourinated refrigerants are included in the category of greenhouse gases and therefore fallunder the F-gas regulation directive. The table below lists the relevant refrigerants and theirrespective GWP (Global Warming Potential) according to the F-gas regulation.

Refrigerant GWP (Global Warming Potential)R134a 1300R407C 1650R404A 3785R507 3850R410A 1975

Requirements of the F-gas regulation include:

• Labelling

• Leakage test

• Recovery of refrigerant

• Certification of personnel

• Log book

Labelling: The unit must be fitted with a label (name plate). Refrigerant type and charge inkg must be stated on the plate.

Leakage test: It is the operator’s responsibility to ensure that the unit is checked for leak-ages by a certified person. For units charged with flourinated greenhouse gases, the followingconditions apply depending on type of plant and amount of charge:

Safety precautions


• Applications containing 3 kg or more of fluorinated greenhouse gases must bechecked for leakage at least once every 12 months.



The applications must be checked for leakage within one month after a leak has been repairedto ensure that the repair has been effective.

For units containing 300 kg or more of fluorinated greenhouse gases leakage detecting sys-tems must be checked at least once every 12 months.

Recovery of refrigerant: Operators must be responsible for putting in place arrangementsfor the proper recovery of fluorinated greenhouse gases by certified personnel to ensure theirrecycling, reclamation or destruction.

Certification of personnel: By 4 July 2008 the member states must establish certificationand training programs for personnel involved in leakage inspections and the recovery, recy-cling, reclamation and destruction of fluorinated gases.

Logbook: For all units containing more than 3 kg fluorinated greenhouse gases a logbookmust be kept indicating the quantity and type of product, quantities added for recharges andthe quantity recovered during servicing, maintenance and final disposal. Other relevant infor-mation is also requested, such as identification of the servicing company or technician as wellas dates and results of the checks.

For further information please see the F-gas regulation in full.

Safety precautions

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5. Sound measurement and noise data

5.1.1 Noise dataIn the following tables the noise data of the compressors is stated in:

- A-weighted sound power level Lw(Sound Power Level)

- A-weighted sound pressure level Lp(Sound Pressure level)

The values for Lw constitute an average of a large number of measurements on various units.The measurements are carried out in accordance with ISO 9614-2.

The values are also stated as average sound pressure in a free field above a reflecting planeat a distance of 1 meter from a fictional frame around the unit.

Normally, the immediate sound pressure lies between the Lw and Lp values and can be calcu-lated, provided that the acoustic data of the machine room is known.

5.1.2 Noise data for screw compressors

Evaporating temperature TE -15°CCondensing temperature TC +35°CRefrigerant R717/HCFC/HFCSpeed 2950 rpm

Type of unit Lw(dBA)

Lp(dBA)

SAB 193 S 103 84SAB 193 L 104 84SAB 233 S 105 86SAB 233 L 106 86SAB 233 E 107 86SAB 283 S 106 88SAB 283 L 107 88SAB 283 E 108 88SAB 283 X 108 88Table 2: Noise data

Sound measurement and noise data


6. Installation

Installation in terms of mechanical work (refrigeration system and piping), electrical work andinstallation of safety equipment must be performed in accordance with local codes/rulesand/or according to EN378-3 and EN378-4 as a minimum requirement.

Make sure that all necessary documents are available including declarations, certificates,identification plates, manuals, machine card, log books etc. and/or other documentation re-quired according to local rules and/or EN378.

The main issues/check points for installation of the compressor unit are as follows:

1. Lifting the unit. Only use the lifting lugs marked with red.Warning! This screw compressor package may be top-heavy.Use caution to prevent unit from turning over.

2. Place the unit with sufficient free space for operation and maintenance.

3. Place the unit on a foundation suitable for the actual load and vibrations. With or with-out vibration dampers according to the vibration design strategy.

4. Welding on suction piping, discharge piping and other oil cooling system pipings.The piping design must include proper design considerations regarding function, vi-brations, thermal expansion and pre-stress after welding in order to avoid high loadon the compressor unit connections.

5. Leak and pressure test according to the applied/local codes and rules. Isolate thecompressor unit from the test pressure or disconnect pressure transducers and safetyvalves. Never exceed the test pressure of the unit stated on the unit name plate.

6. Connect power supply wiring (compressor motor, oil pump motor (optional) and con-trol system) according to electrical diagrams.

7. Electrical installations delivered with the compressor are in conformity with the ATEXdirective. If the installation is extended or additional equipment is mounted it must bein conformity with the ATEX directive. For equipment not delivered by Johnson Con-trols Denmark, it is the contractor who is responsible for the conformity with the pro-visions of the ATEX directive. Especially, the contractor is responsible for equalizingpotential differences on the compressor.

8. Make a final check of all relevant components, connections, electrical connections,safety functions, i.e safety valve, safety high pressure cut-out (below compressorsafety overflow valve and not above 0.9 x max. allowable pressure) and the machineroom safety equipment.

9. Evacuate the unit.

10. Charge oil (type according to Sabroe oil recommendation).

11. Charge refrigerant.

12. Connect power supply.

13. Set up the control system settings including calibration according to the control sys-tem manual.

14. Check the direction of rotation of the compressor motor and oil pump (optional).

15. Mount the coupling.

Installation

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7. Operating instructions

Read chapter 4. Safety precautions carefully before operating the unit.

7.1.1 Description of unitControl system

The compressor unit is controlled by an electronic control system (EC) Fig. 1. The control sys-tem is described in a separate manual, delivered with the unit.

Principle drawing

Fig. 1: Position of valves and components

Operating instructions


Fig. 2: Position of valves and components


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7.1.2 Principle P&I diagramPrinciple P&I diagram

4849-910-4

157

120

135156

121123

195

122

136

138

196

137

124

200

125155

118

107126

102 103

104 105

108

152

117116

160

140

161

106

139

119

193

154144

145

146

157

192

191

127

128114

115

101

129

158113

151

159

133

132

130

131

Fig. 3: Principle P&I diagram



Fig. 4: P&I diagram - optional dual oil filters and demand oil pump


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Legend (Covers all P&I diagrams in this manual)C Compressor TSH Temperature switch high alarmCV Check valve TW ThermowellDP Discharge pressure VI Vi controlFG Flow glass SB-2 Inlet bearing and balance pistonHV Hand valve SB-3 Discharge bearings and sealHTR Heater SC-1 Slide valve - unloadLG Level glass SC-2 Slide valve - loadLSLL Separator low oil level shutdown SC-3 Moveable slide stopM Motor SC-4 Moveable slide stop1MC Motor control centre SC-5 Inlet pressure2MC Motor control centre SC-6 Discharge pressureNOS No oil switch SC-7 Seal weepageOF Oil filter SC-8 Oil drain connectionOP Oil pressure SC-9 Inlet housing oil drainP Demand pump SC-13 Oil drain cylinderPAH High discharge pressure alarm SE-1 Electrical connectionPAHH High discharge pressure shutdown SE-2 Electrical connectionPAL Low pressure alarm SL-1 Liquid injection low ViPALL Low pressure shutdown SL-2 Liquid injection high ViPDAH High pressure differential alarm SM-1 Main oil injectionPDI Pressure differential indicator SV-1 Vapour injection tongue and groovePDSLL Compressor low diff. pressure cut-out SD-1 Coalescer bleed str trh O-ring port TW-1 ThermowellPE Pressure transducer Pressure transducers indicate:PI Pressure indicator PE-1 Oil pressure (manifold)PIC Pressure indicator controller PE-2 Oil pressure before filterPM Pump motor PE-3 Discharge pressurePS Pressure switch control PE-4 Suction pressurePSV High pressure safety valve Temperature probes indicate:SP Suction pressure TE-1 Suction gas temperatureSTR Strainer TE-2 Discharge gas temperatureTAH High temperature alarm TE-3 Lubricating oil temperatureTAHH High temperature shutdown TE-4 Separator oil temperatureTAL Low oil temperature alarm Solenoid valve function:TALL Low oil temperature shutdown YY-1 Energize unload slide valveTC Temperature controller YY-2 Energize increase volume rateTCV Thermal control valve YY-3 Energize increase volume ratioTE Temperature element YY-4 Energize decrease volume ratioTI Temperature indicator YY-5 Solenoid valveTS Temperature switch YY-9 Dual-port liquid injection solenoid



COMPRESSOR LOW VIECONOMIZER ORCLOSED THREAD

LIQUID REFRIGERANTFROM RECEIVER

SOLENOID VALVESTRAINER

LIQUID LINE SIGHTGLASS

MOTORIZEDEXPANSIONVALVE

TUBING LINE

5

170165

Fig. 5: P&I diagram - liquid injection, single port

Fig. 6: P&I diagram - liquid injection, dual port


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Valve position during operationPos. no. Designation In-operation position

101 Suction stop valve Open102 Stop valve after oil separator Open103 Change over valve Open to safety valve - no.1 or no.2

104 / PSV1 Safety relief valve (Closed) Fixed set point105 / PSV 1 Safety relief valve (Closed) Fixed set point

106 Service valve for oil drainage Closed107 Purging valve Closed108 Service valve - “pump out” Closed113 Service valve - pressure transducer Open114 Stop valve Open119 Stop valve before oil filter Open121 Service valve - oil filter Closed122 Service valve - pressure transducer Open123 Stop valve after oil filter Open124 Regulating valve (oil flow) Open (partly) Adjusted acc. to manual125 Service valve - pressure transducer Open126 Cold-start valve Open127 Compressor protection valve (Closed) Controlled by pilot valve128 Pilot valve for pos. 127 (Closed) Fixed set point200 Stop valves - oil return Open

Dual oil filter (optional):135 / 136 Stop valve before oil filter Oil filter 1:

Open 135 - 123Close: 136 - 138

123 / 138 Stop valve after oil filter Oil filter 2:Open 123 - 135Close: 138 - 136

137 Service valve - oil filter ClosedOil pump (optional):

149 Stop valve before oil pump Open

Liquid injection (optional):Single port

165 Liquid stop valve Open170 Stop valve Open

Dual port165 Liquid stop valve Open170 Stop valve Open172 Stop valve Open173 Stop valve Open175 Stop valve Closed

Table 3: Position during operation



7.1.3 Descriptions of main components and systemsThe screw compressor unit is an integrated system consisting of the following major subsys-tems:

• Control system

• Compressor

• Compressor lubrication system

• Compressor oil separation system

• Compressor hydraulic system

• Compressor oil cooling system

• Compressor easy-start system

The information in this section of the manual provides the logical step-by-step instructions toproperly start up and operate the screw compressor unit.

The following subsections must be read and understood before attempting to start or operatethe unit.

7.1.4 CompressorThe rotary screw compressor utilizes mating asymmetrical profile helical rotors to provide acontinuous flow of refrigerant vapour and is designed for both high-pressure and low-pressureapplications. The compressor incorporates the following features:

• Heavy-duty roller bearings to carry radial loads at both the inlet and outlet ends ofthe compressor.

• Heavy-duty, four-point angular-contact ball bearings to carry axial loads are mountedat the discharge end of compressor.

• Balance pistons located in the inlet end of the compressor to reduce axial loads on theaxial load bearings and increase bearing life.

• Movable slide valve to provide fully modulating capacity control from 100% to approx-imately 10% of full load capacity.

• VOLUMIZER® volume ratio control to allow infinitely variable volume ratio from 2.2 to5.0 during compressor operation for all models.

• A hydraulic unloader cylinder to operate the slide stop and slide valve.

• All bearing and control oil vented to closed thread in the compressor instead of suc-tion port to avoid performance penalties from superheating suction gas.

• Shaft seal design to maintain operating pressure on seal well below discharge pres-sure, for increased seal life.

• Oil injected into the rotors to maintain optimum volumetric and adiabatic efficiencyeven at very high compression ratios.

• Shaft rotation clock wise facing compressor, see Fig. 7: Shaft rotation.


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COMPRESSOR

Fig. 7: Shaft rotation

Compressor rotation is clockwise when facing the compressor drive shaft. SeeFig. 7. The compressor should never be operated in reverse rotation as bearingdamage will result.

• Integrated suction strainer on models 100-480 (193-283).

7.1.5 Compressor lubrication systemThe lubrication system on a screw compressor unit performs several functions:

• Provides lubrication to bearings and seal.

• Provides a cushion between the rotors to minimize noise and vibrations.

• Helps keep the compressor cool and prevents overheating.

• Provides an oil supply to hydraulically actuate the slide valve and slide stop.

• Provides oil pressure to the balance pistons to increase bearing life.

• Provides an oil seal between the rotors to prevent rotor contact or gas bypassing.

The compressor unit may be equipped with either a “no pump” or a “demand pump” lubrica-tion system. Additionally, either system may contain:

• Dual oil filters and liquid injection

• Water-cooled or thermosyphon oil cooler for compressor oil cooling

The rotors are constructed with an asymmetrical profile. The male rotor has four lobes andthe female rotor has six, see Fig. 8.

Female Male

Fig. 8: Female/male rotor

A shaft seal is mounted at the shaft end (driving shaft) of the male rotor. The shaft seal en-sures complete tightness between the compressor housing and the compressor shaft, thuspreventing atmospheric air from entering the compressor.

7.1.6 No pump oil systemThe screw compressor unit is designed to be self-lubricating. Oil supplied to the compressorfrom the oil separator is at system head pressure. In the compressor, oil from all lubricatingpoints is returned to a point in the compressor body where the pressure is lower than the



compressor discharge pressure. During normal compressor operation, the compressor unit es-sentially operates as its own oil pump. All oil entering the compressor is moved by the com-pressor rotors out the compressor outlet and back to the oil separator.

For normal high-stage operation an oil pump is not required.

7.1.7 Demand pump oil systemThis system is designed to provide adequate compressor lubrication when the oil differentialpressure across the compressor suction and discharge side is low. It applies to high stage andbooster applications.

On start-up, the control system calculates the differential pressure between the compressordischarge and the main oil injection port. If this differential pressure is less than 2.5 bar [35psi], the demand pump will turn on and continue to run until obtaining a 3 bar [45 psi] differ-ential pressure.

Note: For alarm descriptions and shutdown or cut-out parameters, see separate control sys-tem manual.

7.1.8 Compressor oil separation systemThe compressor is an oil flooded screw compressor. Most of the oil discharged by the com-pressor separates from the gas flow in the oil charge reservoir. Some oil, however, is dis-charged as a mist which does not separate readily from the gas flow and is carried past the oilcharge reservoir. One or more coalescer elements then coalesce the oil mist into dropletswhich fall to the bottom of the coalescer section of the oil separator. See Fig. 9. The return ofthis oil to the compressor is controlled by a throttling valve on both high stage and boosterapplications.

Note: Original: Open needle valves only enough to keep coalescer end of separator free fromoil.

The sight glass located near the bottom of the coalescer section of the oil separator should re-main empty during normal operation. If the oil level rises and remains in the sight glass,there is a problem in the oil return separation system or compressor operation. Refer to chap-ter 9. Maintenance instructions for information on how to correct the problem.

Note: Automatic: Open service valves completely to keep coalescer end of separator free ofoil.

The sight glass in the valve indicates flow variations.

Note: Normal operating oil level is halfway in the top sight glass, which is located midwayalong the oil separator shell.


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Fig. 9: Principle oil separation system



7.1.9 Automatic oil return valve

5

1

51

3

4

6

2

5

1: Inlet G1/4” 2: Filter3: Stop valve, inlet side

4: Stop valve, outlet side 5: Outlet G1/4”6: Sight glass

Fig. 10

Note: Valve inlet and outlet are marked on the valve housing with "in" and “out”.

Function

The function of the automatic oil return valve EVRB is to return the separated oil in the fineseparator to the compressor.

Oil and gas from the fine separator flow into the oil return valve at pos. 1, through the filter,pos. 2, and via the nozzles, pos. 7 and 8, and back to the compressor through the outlet, pos.5, see Fig. 11.

The gas and oil flow through the nozzles, pos. 7 and 8, is adapted to the spring force of pos. 9as well as the viscosity difference between oil and gas. Consequently, the pressure loss of thegas flow through the nozzle, pos. 7, is unable to move the piston, pos. 7.

However, the pressure loss of the oil flow through the nozzle, pos. 7, is able to move the pis-ton, pos. 7.

Thus the spring force, pos. 9, is equalized and a transverse bore, pos. 10, with a considerablylarger bore than pos. 7 will open.

Because the bore is larger, oil collections at the oil return valve inlet can quickly be removed.

When the oil has been removed, the gas flow will rise and the piston, pos. 7, will close thetransverse bore. The gas flow will be lowered to a minimum.

Through the sight glass, pos. 6, it is possible to watch the oil return. As a small amount of gaswill always pass through the nozzle, pos. 7, gas bubbles will be visible.

The valve can be serviced by closing the stop valves, pos. 3 and 4.


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6 8 10

2

79

15

InOut

34

Fig. 11

Note: The sectional view shows the valve structure. Not all internal oil channels are visible.



7.1.10 Cold-start systemThe unit is equipped with a special "cold-start" discharge valve, see Fig. 12. This valve en-sures a rapid development of oil pressure at initial start-up in order to lubricate the compres-sor without requiring an oil pump, even in cold ambient temperatures with all pressuresequalized.

High-stage units

For high-stage units, the cold-start valve is equipped with a large spring which creates a 2.0bar [30 psi] pressure in the oil separator (above suction pressure) for lubrication of the com-pressor.

Once the compressor is running it will begin to force gas to the condenser at connection P2.

As the condenser heats up, the pressure will begin to rise as the compressor suction pullsdown in pressure. As soon as a differential pressure has developed between the condenserand suction side, these pressures will act across a piston inside the cold-start valve to partial-ly overcome the spring force. When the differential pressure reaches and exceeds 2.0 bar [30psi], the piston fully overcomes the spring force and powers the valve fully open for very lowoperating pressure drop.

Booster applications

For booster applications, the valve is equipped with a light spring which produces 0.5 bar [7psi] oil pressure above suction pressure before it fully powers open. An oil pump is required toensure compressor lubrication.

The unit is also equipped with a suction check valve by-pass. The oil separator will slowlybleed down to approximate system suction pressure when the unit is stopped. This allows thecompressor drive motor to have an easier start, and the discharge check valve will seat moretightly. See section 7.1.14. Suction check valve by-pass for operation.

Note: For alarm descriptions and shutdown or cut-out parameters, see separate control sys-tem manual.

OPENCLOSED

P3 - TO SUCTION

P2 - TOCONDENSER

P1 - FROMOIL SEPARATOR

P1

P2

P3

Fig. 12: Cold-start valve


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7.1.11 Compressor hydraulic systemThe compressor hydraulic system moves the movable slide valve (MSV) to load and unloadthe compressor. It also moves the movable slide stop (MSS) to increase or decrease the com-pressor’s volume ratio (Vi).

The hydraulic cylinder located at the inlet end of the SGC compressor serves a dual purpose.It is separated by a fixed bulkhead into two sections. The movable slide valve (MSV) section isto the left of the bulkhead and the movable slide stop (MSS) to the right. Both sections areconsidered double-acting hydraulic cylinders as oil pressure moves the pistons in either direc-tion.

Both sections are controlled by double-acting, four-way solenoid valves which are actuatedwhen a signal from the appropriate microprocessor output energizes the solenoid valve.Valves V1, V2, SC1, SC3 and SC4 are always open.

Single-acting mode - High stage

• Close valve at SC2

• Open valve at BP (by-pass)

High stage compressor loading. The compressor loads when MSV solenoid YY2 is ener-gized and oil flows from the unload side of the cylinder out port SC1, through valve ports Aand T to compressor suction. Simultaneously, discharge pressure loads the slide valve.

High stage compressor unloading. The compressor unloads when MSV solenoid YY1 isenergized and oil flows from the oil manifold through valve ports P and A to cylinder port SC1and enters the unload side of the cylinder. Simultaneously, gas on the load side of the cylin-der is vented through port SC2 and valve BP to compressor suction.

Note: To control the rate of loading and unloading, change cycle time, proportional band anddead band setpoints with the control system. If additional control is needed, throttle SC2 orBP.

Double-acting mode - Booster

• Open valve at SC2

• Close valve at BP (by-pass)

Booster compressor loading. The compressor loads when MSV solenoid YY2 is energizedand oil flows from the oil manifold through valve ports P and B to cylinder port SC2 and entersthe load side of the cylinder. Simultaneously, oil contained in the unload side of the cylinderflows out cylinder port SC1 through valve ports A and T to compressor suction side.

Booster compressor unloading. The compressor unloads when MSV solenoid YY1 is ener-gized and oil flows from the oil manifold through valve ports P and A to cylinder port SC1 andenters the unload side of the cylinder. Simultaneously, oil contained in the load side of thecylinder flows out of compressor port SC2 through valve ports B and T to compressor suctionside.

Note: To control the rate of loading and unloading, change cycle time, proportional band anddead band set points with the control system. If additional control is needed, throttle SC2 orBP.

Note: To slow all valve movements - loading, unloading and Vi change - throttle valve 2.



Fig. 13: Volumizer volume ratio control

Caution!

Never open valve BP and valve SC2 at the same time during compressor operation.

7.1.12 Volumizer volume ratio controlNote: See Fig. 14: Compressor hydraulic system for port references.



Compressor Vi increase. The volume ratio Vi is increased when MSS solenoid valve YY3 isenergized and oil flows from the oil manifold through valve ports P and A to compressor portSC3, enters the increase side of the cylinder and overcomes the decrease spring tension. Si-multaneously, oil flows from SC4 port through valve ports B and T to compressor suction.

Compressor Vi decrease. The volume ratio Vi is decreased when MSS solenoid valve YY4 isenergized and oil flows from the oil manifold through valve ports P and B to compressor portSC4, enters the decrease side of the cylinder. Simultaneously, oil flows from SC3 port throughvalve ports A and T to compressor suction.

To control the rate of Vi change, throttle the needle valve at SC3 port.

7.1.13 Compressor oil cooling systemsThe unit can be equipped with one of several systems for controlling the compressor oil tem-perature. They are single or dual-port liquid injection and refrigerant cooled (thermosyphon)or water-cooled oil coolers. Each system is automatically controlled, independent of compres-sor loading or unloading.

Oil cooling systems should maintain oil temperature within the following ranges for R-717 andHCFC/HFC:


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Liquid injection

oil cooling

External*

oil cooling

55-77°C

[130-170°F]

49-71°C

[120-160°F]

* : Refrigerant cooled (Thermosyphon) oil cooling (TSOC) or water-cooled oil cooling (WCOC.)

Table 4: Oil cooling

Fig. 14: Compressor hydraulic system

Single-port liquid injection. The single-port liquid injection system is designed to permitliquid refrigerant injection into one port on the compressor at any given moment and operatesas outlined.

Solenoid valve YY5 is energized by the micro processor when the temperature sensor, instal-led in the compressor discharge, exceeds the LIOC (Liquid Injection Oil Cooling) set point.High-pressure liquid refrigerant is then supplied to the temperature control valve (TCV). Referto section 7.1.2. Principle P&I diagram .

Dual-port liquid injection. The dual-port liquid injection system is designed to obtain themost efficient compressor performance at high and low compression ratios by permitting in-jection of liquid refrigerant into one of two ports optimally located on the compressor. Thisminimizes the performance penalty incurred with liquid injection oil cooling.

The dual-port system contains all the components of the single-port system with the additionof a double-acting solenoid valve YY9 and operates as outlined.



Solenoid valve YY5 is energized by the microprocessor when the temperature sensor, installedin the oil manifold, exceeds the LIOC set point. Liquid refrigerant is then passed through thetemperature control valve (TCV) to the double-acting solenoid valve YY9. Depending on thecompressor’s operating volume ratio (Vi), the microprocessor will select the flow of the liquidrefrigerant to either compressor port SL-1 or SL-2, whichever is more efficient.

When the compressor operates below 3.5 Vi, compressor port SL-1 supplies the liquid cooling.When the (Vi) rises above 3.5 Vi, port SL-2 supplies the liquid cooling.

Liquid injection adjustment. For discharge temperature set point and PID regulator param-eters, refer to the operating manual for the control system. The discharge temperature setpoint is set to the required oil temperature, see section 7.1.13. Compressor oil cooling sys-tems .

7.1.14 Suction check valve by-passThe unit is equipped with a low-pressure-drop suction check valve bolted directly to the com-pressor housing. Units with an 8" stop valve or larger will be piped as shown in Fig. 15. Dur-ing normal operation, valve NV-1 is closed. This is a pump-out connection to allow refrigerantremoval to the system suction prior to evacuation for servicing. In most systems, valve NV-2must be open at all times. It should normally be cracked open to allow the oil separator toslowly bleed down to approximately system suction pressure when the unit is stopped (havingthis valve cracked open allows the compressor drive motor to have an easier start and thedischarge check valve will seat more tightly). If the drive coupling backspins, start closing thevalve until the backspin stops. If the separator oil level foams excessively on shutdown, NV-2should be closed slightly. If the separator takes more than 20-30 minutes to equalize to suc-tion pressure after shutdown, NV-2 can be opened slightly. See Fig. 15.

FROMSEPARATORCOLD-START

VALVE

FOR 8” AND LARGER SUCTION VALVECUSTOMER SUPPLIED LINE

COMPRESSOR END VIEW

SUC

TIO

N G

AS

TO T

HE

CO

MPR

.

Fig. 15: Suction check valve by-pass

Check valve CV-4 is installed on all units with suction pressure below atmospheric or installedwith economizer option utilized on multiple compressor plants.

On high-stage systems, check valve CV-4 should be installed with a 3.1 bar [45 psi] spring toavoid the possibility of back-feeding to a shutdown compressor from a common economizervessel.


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On booster systems, check valve CV-4 should be installed with a 1.7 bar [25 psi] spring toavoid the possibility of air ingress into the system if the system suction pressure is below at-mospheric.

NV-2 must be closed if the oil pump should run for long periods of time when the compressoris stopped. This is important in order to avoid oil being pumped up the suction line.

7.1.15 Low ambient temperature operationIt is recommended that oil separators are insulated as a minimum requirement to preservethe heat generated by the oil heaters. It is important that the coalescer end of the separatoris insulated to prevent refrigerant condensation.

On systems located outdoors or in unheated buildings where the ambient temperature maydrop below 5°C [+41°F], insulating and/or heat tracing of the compressor lubricating oil sys-tems is highly recommended.

When low ambient temperatures (below -7°C [+20°F]) may occur, it is recommended to heattrace and insulate lubricating oil lines, oil filters, oil pumps and oil coolers.

Freeze-up protection must also be provided for all water-cooled equipment.



7.1.16 Start-up

Preparations before start up

1. Turn on the power voltage and the control voltage. Check the emergency stop button.

2. Check the oil level in the oil separator. Oil level visible in the upper sight glass.

Warning!

ATEX: Max. oil temperature: 65°C

3. Check that all valves are positioned in accordance with Table 3: Position during opera-tion Position during operation, including secondary side of oil cooler.

4. Reset any alarm in accordance with the instructions for the control system.

5. Check on the control display that the compressor capacity control system is in mini-mum slide pos. 0-4%.

Initial start-up procedure

The personnel who are going to start up the plant must be well-qualified and have a thoroughknowledge of refrigeration technique. Prior to start-up, the prestart check must be accom-plished.

Having performed the checkpoints on the installation and preparation before start check list,the compressor unit is ready to start up. It is important that an adequate refrigerant load beavailable to load test the unit at normal operating conditions. The following points should bekept in mind during initial start-up.

• During the initial start-up of the unit it is imperative that the hand expansion valve onthe main oil injection line is fully open to ensure adequate oil flow.There is still an orifice installed in the compressor to control maximum oil flow. At ini-tial start-up of the compressor the hand expansion valve must be fully open. After ini-tial start-up of the unit the hand expansion valve should be adjusted.

First method.The best method to determine target discharge temperature is to run CoolWare™/Comp 1.Run CoolWare™/Comp 1 or ScrewSelect with the operating conditions of the compres-sor. The program will give you a theoretical discharge temperature of the compressor.Once this temperature is known, you may adjust the hand expansion valve. The idealdischarge temperature is within +2.7°C or -2.7°C [5°F + or –5°F] of the theoreticaldischarge temperature. Adjust the valve to achieve the theoretical discharge tempera-ture.

Second methodIf you do not have access to CoolWare™/Comp 1 or ScrewSelect, 82°C [180°F] is agood target discharge temperature for a high stage ammonia compressor. Booster ap-plications and compressors using HFC and HCFC refrigerants may run cooler. Com-pressors with high discharge pressure may run hotter.

The first method is used for compressors with external oil cooling (Refrigerantcooled (thermosyphon), water-cooled and glycol-cooled).Before the initial start-up of the compressor close the hand expansion valve complete-ly. Open the valve back up and count the turns that it takes to fully open the valve.


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After the initial start-up close the valve to achieve approximately 82°C [180°F] dis-charge temperature or the theoretical temperature from CoolWare. Do not fully closethe valve at any time while the compressor is running.

The second method is used for compressors with liquid injection oil cooling. Becausethe discharge temperature is controlled by the liquid injection thermal expansionvalve you will not be able adjust for the correct oil flow by using the discharge tem-perature.Before the initial start-up of the compressor close the hand expansion valve complete-ly. Open the valve back up and count the turns that it takes to fully open the valve.After the initial start-up close the valve ½ way. If it took 10 turns to open the valvecompletely, then turn it in 5 turns. If it took 7 turns to open, then close the valve 3½turns. Do not close the valve any further than ½ the number of turns required to fullyopen it.Failure to properly adjust this valve can lead to excessive noise and vibrationof the compressor and unit, premature failure of the bearings, liquid loadingof the rotors, liquid starvation of the rotors and catastrophic failure of thecompressor.

• For proper and safe operation, the compressor must be run at the proper speed anddischarge pressure. Exceeding design conditions creates a potential hazard.

• Rotate and lubricate motor bearings according to manufacturer’s recommendationsPRIOR to initial start-up as required.

• After running the unit for approximately three hours, adjust liquid injection oil coolingif applicable. If unit has water cooled oil cooling, adjust water control valve to cooler.

• The compressor slide valve and slide stop linear transmitters should be calibrated.

• Perform vibration analysis if equipment is available.



Normal start-up procedure

1. Check/perform the Preparations before start-up.

2. Confirm that the system conditions permit the compressor to start.

3. Press the start button.

4. Allow the compressor to start up and stabilize.

5. Observe the compressor unit for mechanical tightness of the external piping, bolts andvalves. Ensure that the unit is clean from oil and refrigerant leaks. If not satisfactory,shut down the compressor and correct the problem using good safety precautions.

Restarting compressor unit after control power interruption (plant power failure)

• Check variable set points.

• Follow normal start-up procedure.


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7.1.17 Stopping routine

Brief stop

The compressor can be stopped at any capacity setting. However, under normal conditions itis recommended to reduce the capacity to a minimum before stopping the compressor.

Leave all valves in their “in-operation positions”. Do not turn off the power to the screw com-pressor unit as the oil heater must be connected to keep the correct oil temperature.

Shutting down for a long period

Follow the Brief stop instructions and:

• Disconnect oil heater

• Close suction and discharge valve(and liquid line for ECO and liquid injection) (optional)

To perform servicing and repair work, the necessary valves must be closed.

To reduce the risk of bearing damage it is recommended to rotate (to a new position) the mo-tor and compressor on a monthly basis. If the screw compressor unit is exposed to vibrationsduring a long shutdown period, the interval should be changed to weekly.

Avoid high vibration level.



8. Troubleshooting

The tables below cover the most common problems. For detailed troubleshooting of the refrig-eration plant, please refer to the manual of the plant or common refrigeration literature.

Refrigeration plant - generalSymptom Probable cause Correction

Suction pressure- excessively low

Refrigeration load lower than com-pressor capacity.

Reduce compressor capacity.

High suction line loss. Check valves, strainers etc.

Malfunction of evaporator.

Check evaporator (fouling, accu-mulated oil etc.), liquid expansionvalve system, filter in liquid line,refrigerant charge (insufficient).

Discharge pressure- excessively high

Safety cut-out set too low.Check the setting of alarms andwarnings (control system) and theseparate safety pressure cut-out.

High discharge line loss. Check valves, check valve etc.

Malfunctioning of condenser.

Check condenser, liquid drain fromcondenser, refrigerant charge (toomuch), water/air inlet temperature(too high), water/air flow (too low).

Air/non-condensable gasses in thesystem.

Purge the air from the condenserside.

Table 5: Refrigeration plant - general

Troubleshooting

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Compressor unit - generalSymptom Probable cause Correction

Compressor cannotstart

Electrical supply.Check main switch and fuses. Re-set emergency stop switch etc.

Alarm in control system.Register the alarm, correct if nec-essary and reset (refer to the Con-trol manual).

Oil level too low. Charge oil.Compressor startsbut stops immedi-ately

Oil system failure (temperature,pressure, level)

Check oil level.Check valve positions.

Oil filter differentialpressure too high

Oil filter clogged. Replace oil filter

Oil temperature toohigh (and high dis-charge tempera-ture)

Valves in oil system are not fullyopen.

Check stop valves and opening po-sition of the oil regulation valve

3-way oil temperature controlvalve. (Water-cooled or refrigerant-cooled (Thermosyphon)).

Check function, replace the sensorelement.

Insufficient oil cooling function(water-cooled).

Check oil cooler, fouling, water in-let temperature, (too high), waterflow (too low).

Insufficient oil cooling function(refrigerant-cooled)

Check/drain accumulated oil in theoil cooler. Check that the gravityfeeded refrigerant system is fullflooded.

Insufficient oil cooling function(liquid injection).

Check the settings in control sys-tem, valves and strainer in Liquidinjection line,

Compressor protection valve isopen or leaking.

Check the discharge pressure safe-ty cut-out settings. Check the pilotand main protection valve.

Discharge tempera-ture very low. Oiltemperature lowand oil may befoaming in oil sepa-rator

Excessive liquid in suction line/ liquid slugging.

Check evaporator (and economizer(optional)) and expansion valvefunction. Decrease the rate ofevaporator temperature “pulldown”.

Liquid injection (optional) overfeed-ing.

Check the settings in control sys-tem (increase the set point). Checkthe stability of the liquid injection.

Suction pressurehigh and insufficientrefrigeration capaci-ty

Compressor protection valve isopening or leaking.

Check the discharge pressure safe-ty cut-out settings. Check the pilotand main protection valve.

Oil return valve fully open.Adjust the regulating valve accord-ing to manual.

Suction strainer clogged. Clean strainerTable 6: Compressor unit - general

Troubleshooting


Compressor unit - oil separationSymptom Probable cause Correction

Gradual oil loss withan oil level in thecoalescer sectionsight glass

Maintaining too high oil level.Lower level by opening/adjustingthe oil return valve.

Refrigerant carry-over or liquid in-jection overfeeding.

Correct operation.

Loss of suction superheat. Adjust evaporator feeds.Contaminated oil, damaged or notseated coalescer elements.

Replace oil charge and coalescers.

Coalescer return valve closed. Open return valve.Coalescing oil return line strainerblocked.

Clean strainer.

Rapid loss with nooil level in the coa-lescer section sightglass

On shutdown, compressor unit suc-tion check valve did not close.

Repair valve.

Suction check valve bypass opentoo far.

Close valve.

Coalescers loose or not seatedproperly.

Correct or replace.

On economized unit: economizercheck valve not working.

Repair or replace.

Shaft seal leakage Leakage exceeds normal allowablerate of 7 drops per minute.

Replace seal.

Table 7: Compressor unit - oil separation

Compressor blockSymptom Probable cause Correction

Excessive noise andvibration

Main oil injection valve may beclosed.

Open valve.

Main oil injection valve may beopen too far.

Adjust.

Bearing damage or excessive wear. Replace bearings.Slide valve/slide stop out of cali-bration (over or under compres-sion).

Calibrate.

Coupling loose on shaft.Tighten coupling. Replace if dam-aged.

Refrigerant flood back (Liquid slug-ging).

Correct system problem.

Capacity slide valveand/or slide stopwill not move.Cannot unload/loador both

Oil pressure is not sufficient. Check oil pressure.Solenoid coils may be burned out. Replace.Incorrect setting of valves in thehydraulic system.

Check according to hydraulic sys-tem description.

Malfunction of 4-way control valveof slide components.

Check according to description ofmain components.

Table 8: Compressor block

Troubleshooting

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Demand oil pump system (optional)Symptom Probable cause Correction

Pump will not pro-duce enough oilpressure to startcompressor

Pump rotation. Check.Service valves closed. Open valve.

Filter cartridges may be blocked.Check pressure difference acrossfilters.

Strainer may be blocked. Clean strainer.Oil pressure regulator set too lowor stuck open

Readjust or repair.

Pump worn out. Repair or replace.Hand expansion valve (pos. 124)may be opened too much.

Throttle the valve.

Oil pressure rapidlydrops off whencompressor starts.Results in compres-sor differentialalarm

Main oil injection throttling valvetoo wide open or oil pressure regu-lating valve improperly adjusted.

Readjust both valves.

Oil pressure fluctu-ates

Liquid injection overfeeding or re-frigerant flood back from system.

Make necessary adjustments orcorrections.

Noise and vibra-tions

Pump strainer blocked. Clean strainer.Liquid refrigerant overfeed. Adjust liquid injection.Pump worn out. Repair or replace.

Grease leaks fromvent port in theside of the pumpbody

Normal leakage which will cease af-ter initial operation. Black oil leak-ing from this vent indicates oil sealwear or failure.

If leakage exceeds normal allowa-ble rate of 7 drops per minute, re-place seal.

Main filter pressuredifference is toohigh

Filters clogged with dirt. Replace filters.Oil is too cold. Allow oil to warm up.Service valve on filter outlet is par-tially closed.

Open valves fully.

Table 9: Demand oil pump system (optional)

Troubleshooting


9. Maintenance instructions

9.1.1 Maintenance of compressor unitRead chapter 4. Safety precautions carefully before performing any maintenance on the com-pressor unit.

To ensure that the compressor unit operates without problems throughout a long service life,the system of maintenance presented in the following instructions must be followed.

Daily maintenance is normally performed by operating personnel. Other maintenance andservice tasks which require the refrigeration system to be opened must be performed by au-thorized personnel.

Maintenance can be divided into 3 groups:

1. Daily maintenance(minimum twice a week)Daily maintenance consists of visual inspections.

• Inspect the compressor unit and check that both noise and vibrations are nor-mal.

• To observe trends it is recommended to enter the observed operating data in-to the operations log, see section 9.1.2. Operations log. Check that all oper-ating values are within the permissible ranges. Compare them with previousvalues to detect trends.

• Check the oil level in the oil separator.

• Check the refrigerant charge.

• Observe for leaks of refrigerant (smell of R717), oil or water.

• Check mechanical seal oil draining bottle.

• Check the control system for alarms/shutdowns.

2. Periodic maintenanceMotor lubrication and other routine maintenance tasks are usually based on runningtime. Please refer to Table 10: Maintenance intervals.

3. Major overhaulFor major maintenance tasks such as compressor overhauls, contact Johnson ControlsDenmark.

Maintenance instructions

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Main

ten

an

ce in

terv

als

Main

ten

an

ce s

ched

ule

Ho

urs

op

era

tio

n (

maxim

um

)

200

1000

5000

8000

10000

15000

20000

25000

30000

35000

40000

45000

50000

55000

60000

65000

70000

75000

80000

85000

90000

95000

Chan

ge

oil

As

direc

ted b

y oil

anal

ysis

Oil

anal

ysis

x

Eve

ry 6

month

sChan

ge

filter

sx

x

x

x

x

x

x

x

x

x

x

Cle

an o

il st

rain

ers

x

x

x

x

x

x

x

x

x

x

x

Cle

an liq

uid

str

ainer

sx

x

x

x

x

x

x

x

x

x

x

Chan

ge

coal

esce

rs (

d)

x

x

x

x

x

x

Chec

k an

d c

lean

suct

ion s

cree

nx

xx

x

x

x

x

x

x

x

x

x

Chec

k al

ignm

ent

(e)

x

x

x

x

x

x

x

x

x

x

x

Chec

k co

uplin

g (

a)x

Annual

ly r

egar

dle

ss o

f oper

atin

g h

ours

Chec

k el

ectr

ical

connec

tions

(b)

x

x

xx

xx

xx

xx

xx

xx

xx

xx

xx

Chec

k se

nso

r ca

libra

tion (

c)x

xx

x

xx

xx

xx

xx

xx

xx

xx

xx

xVib

ration a

nal

ysis

(f)

xEve

ry 6

month

s, m

ore

fre

quen

tly

if lev

els

incr

ease

Rep

lace

shaf

t se

alW

hen

lea

k ra

te e

xcee

ds

7 -

8 d

rops

per

min

ute

(a)

Chec

k bolts,

shim

pac

ks,

centr

e in

sert

s, k

eys

and a

ll bolt t

orq

ue.

(b)

Chec

k an

d t

orq

ue

all te

rmin

als

in t

he

pro

cess

or

and s

tart

er p

anel

per

the

spec

ific

atio

n p

ost

ed in t

he

encl

osu

re.

(c)

Chec

k ca

libra

tion o

f sl

ide

valv

e, s

lide

stop a

nd p

ress

ure

.

(d)

Boost

er:

20,0

00 h

. H

igh s

tage/

air

conditio

nin

g:

10,0

00 h

. O

ne

stag

e: 3

0,0

00 h

.

(e)

Not

for

flan

ge

moto

rs.

(f)

Vib

ration m

easu

rem

ent

must

be

carr

ied o

ut

continuousl

y to

obta

in o

ptim

um

pre

ventive

contr

ol on b

earings.

If not

continuousl

y co

ntr

olle

d t

hen

ever

y 6 m

onth

s, m

ore

fre

quen

tly

if lev

els

incr

ease

. Alter

nat

ivel

y, m

ajor

ove

rhau

l af

ter

max

imum

30000 h

.

(g)

Ver

ify

tightn

ess

of bolts

on s

uct

ion a

nd d

isch

arge

flan

ges

on a

dai

ly b

asis

. See

Tab

le 1

1 for

torq

ue

requirem

ents

.

Leak

tes

t: A

ccord

ing t

o n

atio

nal

rule

s or

as a

min

imum

acc

ord

ing t

o E

N 3

78-2

(M

inim

um

annual

ly if le

ak r

ate

< 1

% y

ear)

Saf

ety

equip

men

t: C

hec

k of sa

fety

equip

men

t (S

afet

y sw

itch

dev

ices

, pre

ssure

rel

ief

valv

e) a

ccord

ing t

o n

atio

nal

rule

s. M

inim

um

req

uirem

ent

ac-

cord

ing t

o E

N 3

78,

annual

chec

k of

safe

ty s

witch

dev

ices

and e

very

5 y

ears

for

pre

ssure

rel

ief va

lve.

Table 10: Maintenance intervals



EUdesignation

ReferencemodelRWF II

Compressormodel

Discharge flange toseparator flange

Suction flange

Bolt size Torque(ft-lb)

Bolt size Torque(ft-lb)

SAB 193 S 100 SGC 1913 M20 x 2.5 140 M20 x 2.5 180SAB 193 L 134 SGC 1918 M20 x 2.5 140 M20 x 2.5 160SAB 233 S 177 SGC 2313 M20 x 2.5 160 M20 x 2.5 160SAB 233 L 222 SGC 2317 M20 x 2.5 160 M20 x 2.5 200SAB 233 E 270 SGC 2321 M20 x 2.5 160 M22 x 2.5 220SAB 283 S 316 SGC 2813 M22 x 2.5 230 M22 x 2.5 220SAB 283 L 399 SGC 2817 M22 x 2.5 230 M22 x 2.5 220SAB 283 E 480 SGC 2821 M22 x 2.5 230 M24 x 3.0 220SAB 355 S 496 SGC 3511 M24 x 3.0 240 M30 x 3.5 350SAB 283 X 546 SGC 2824 M22 x 2.5 240 M24 x 3.0 220SAB 355 L 676 SGC 3515 M24 x 3.0 240 M30 x 3.5 350SAB 355 E 856 SGC 3519 M24 x 3.0 240 M30 x 3.5 350SAB 355 X 1080 SGC 3524 M24 x 3.0 240 M30 x 3.5 350Table 11: Torque requirements

Note: * Based on:

a. Gaskets-Garlock® Blue-Gard® 3300

b. Bolts-class 8.8 or stronger hex head bolts, lightly oiled and clean


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9.1.2 Operations logTo ensure satisfactory operation, it is recommended to enter the following routines in a log-book. The service engineer will need this information in connection with e.g. error reports. Inaddition to the data mentioned in Table 12, all other activities of service, maintenance or re-pair work must be entered into the logbook as required by EN 378 and national laws.

Compressor type/no.: _______________Refrigerant: _______________Oil type: _______________

Check list Normal lev-el

Date and time

From ToSuction pressure (bar) Suction temperature (°C) Superheating, suction gas (K) Discharge pressure (bar) Discharge temperature (°C) Oil pressure, compressor (bar) Oil diff. pressure, filter (bar) Oil temperature (°C) Oil level (upper/lower glass) Charged oil (litre) Operation time (hours) Volume ratio Capacity load, % Other observationsRefrigerant leaks Oil leaks Oil drain bottle (shaft seal) Vibration/noise Unisab control:Alarm/Shutdown

Other serviceor repair work

Table 12: Monitoring of operation



9.1.3 OilThe oil separator in the screw compressor unit has an integrated oil reservoir. The oil is usedfor lubrication, cooling, sealing and regulation of the capacity slide.

• Only use oil according to Sabroe oil recommendation.

• Oil is added via the oil pump/oil charging valve.

• Check the oil level in the oil separator. It must not be higher than the upper sightglass. Oil must be added when the level reaches the lower sight glass. The correctlevel appears only when the unit is operating.

• If the oil level is too low, check for leaks and possible insufficient oil return from therefrigeration plant.

• The oil level will rise approx. 10 mm if the indicated amount of oil is charged, see Ta-ble 13: Oil charging.

Oil change

The oil in the unit must be changed after a specific number of operating hours or when an oilanalysis shows that the oil needs to be changed.

We advise you to let Johnson Controls Denmark’s service organization change the oil as it isrecommended to replace all filters in the unit at the same time.

Type of unit Basicoil charge

Basicoil charge

Amount of oilper 10 mm

Amount of oilper 10 mm

Litres Gal. Litres Gal.SAB 193 S 170 45 8 2SAB 193 L 170 45 8 2SAB 233 S 360 95 12 3SAB 233 L 360 95 12 3SAB 233 E 473 125 15 4SAB 283 S 492 130 15 4SAB 283 L 492 130 15 4SAB 283 E 530 140 19 5SAB 283 X 530 140 19 5Table 13: Oil charging


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Oil charging pump

Oil charging is carried out by means of a portable oil charging pump as described below. SeeFig. 16: Oil charging.

1. Connect the high-pressure hose, pos. 7, to the charge valve, pos. 24, on the unit vianon-return valve, pos. 12. Use correct reduction nipple. See Fig. 17: Oil charging dia-gram.

2. Place the free end of the suction hose from the pump, pos. 1, together with the by-pass hose, pos. 2, in the oil barrel.

3. Ball valve pos. 9, and the charge valve, pos. 24, will open and the pump, pos. 5, willstart.

4. The oil now circulates until the system is free from air bubbles after which the ballvalve, pos. 9, will close. The oil will now be charged to the unit.

5. When the desired amount of oil has been charged, the pump will stop and the chargevalve, pos. 24, will close.

6. Open the ball valve, pos. 9, carefully so that the pressure is equalized. The hoses cannow be dismounted.

7. Loosen the non-return valve carefully so that the remaining pressure is equalized. Re-member to mount the cap nut on the charge valve and to seal the oil barrel if there isany oil left.

Length: 460 mmHeight: 350 mmWidth: 340 mmWeight: 22 kgPart number: 4541.001

3/8”RG

1/4”RG

1/2”RG

7/8”RG

RG= Pipethread

20

7

9

5

1

2

12

Fig. 16: Oil charging



5

20

2

1

B

9

7

12

M

A

24

Fig. 17: Oil charging diagram


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9.1.4 Motor

Motor lubrication

In connection with electric motors, it is absolutely essential to lubricate the bearings correctlyand use the appropriate type of grease.

Please refer to the motor manual and/or the motor name plate.

Replacing motor bearings

Please contact Johnson Controls Denmark’s service organisation.



10. Final disposal

10.1.1 Safety precautions

Danger!

Before dismantling the plant, read the safety precautions carefully.

Dismantling a cooling unit to be scrapped must be carried out safely.

Authorized refrigeration personnel must participate in the first part of the dismantling processas fundamental knowledge of refrigeration systems and the risks involved is required.

Before dismantling the plant, refrigerant and oil must be drained into suitable containers. Dis-connect all electrical connections to the unit and remove fuses in the main switchboard.

During the dismantling process, the individual machine parts and components must be sortedto ensure proper disposal. All waste must be transported to receiving stations which complywith the prevailing national rules and regulations.

Danger!

Be very careful when using cutting tools such as angle grinders or flame cutters during thedismantling process as pipes and the like contain oil residue which may ignite. Refrigerantresidue also involves a great risk as HFC and HCFC refrigerants develop toxic gasses whenheated. Make sure that there are no air traps as heating results in a pressure rise.

10.1.2 Disposal of

• Machine partsWhen dismantling the plant, it is important to sort the parts to be disposed of. Com-pressor, frame, containers etc. belonging to the category of iron and metal scrap mustbe brought to an approved scrap dealer who complies with the prevailing nationalrules and regulations.

• Oil and refrigerantOil and refrigerant must be brought to a receiving station for hazardous waste for de-struction or regeneration. This also applies to used oil filters. The receiving stationmust comply with the prevailing rules and regulations of the individual country. Donot transport oil in open vessels in a closed car.

• Electrical componentsElectrical and electronic products, e.g. wiring, panels, hardware etc., must be broughtto a receiving station approved to handle electronic waste. The receiving station mustcomply with the prevailing rules and regulations of the individual country.

• BatteriesUsed batteries from e.g. the backup of the computer control must be brought to a re-ceiving station for destruction. The receiving station must comply with the prevailingrules and regulations of the individual country.

Final disposal

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11. Appendices

All relevant instructions for products supplied by sub-suppliers are collected here.

11.1.1 Declaration of conformityJohnson Controls Denmark declare on the signed declaration of conformity that the machine ismanufactured and CE-marked in accordance with relevant directives and standards.

On the next two pages you can see a declaration of conformity, however not filled in with thespecific data. It may occur that the original signed declaration of conformity is sent separate-ly. If so, it will be based on a clear written agreement between the customer and JohnsonControls Denmark.

Appendices


Appendices

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Appendices


Index

AApplication of combustion engines 8

Automatic oil return valve 34

Bbooster applications 36

Brief stop 45

CCold-start system 36

Compressor 30

compressor hydraulic system 37

Compressor lubrication system 31

Compressor oil cooling systems 38

Compressor oil separation system 32

Compressor Vi increase 38

Cooling water system 16

DDemand pump oil system 32

Description of unit 23

Descriptions of main components and systems 30

Disposal 58

Dual-port liquid injection 39

During operation 15

FF-gas regulation 19

Hhigh-stage units 36

LLiquid injection adjustment 40

Low ambient temperature operation 41

Lubricating oils 18

MMaintenance intervals 51

Maintenance of compressor unit 50

Motor lubrication 57

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NNo pump oil system 31

Noise data 21

Normal start-up procedure 44

OOil change 54

Oil charging pump 55

Operations log 53

PPower supply 18

Pressure 16

Principle P&I diagram 25

Purging 19

RRefrigerants 18

Replacing motor bearings 57

Rotating parts 15

SSafety precautions 7, 58

Shutting down for a long period 45

Single-port liquid injection 39

Stopping routine 45

Suction check valve by-pass 40

UUnit/pipe system name plate 9

VValve position during operation 29

Vessel name plate 13

Vibration and noise 15

volume ratio Vi is decreased 38

Volumizer volume ratio control 38


sab 193, 233, 283 atex screw compressor...

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