GEA FK50/460 N User manual

GEA Compressor FK50
Assembly instructions
09704-06.2016-Gb
Translation of the original instructions
FK50/460 N FK50/555 N FK50/660 N FK50/775 N FK50/830 N FK50/980 N
FK50/460 K FK50/555 K FK50/660 K FK50/775 K FK50/830 K FK50/980 K
FK50/460 TK FK50/555 TK FK50/660 TK FK50/775 TK
FKX50/460 N FKX50/555 N FKX50/660 N FKX50/775 N FKX50/830 N FKX50/980 N
FKX50/460 K FKX50/555 K FKX50/660 K FKX50/775 K FKX50/830 K FKX50/980 K
FKX50/460 TK FKX50/555 TK FKX50/660 TK FKX50/775 TK

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About these instructions
Read these instructions before assembly and before using the compressor. This will avoid
misunderstandings and prevent damage. Improper assembly and use of the compressor can lead to
serious or fatal injury.
Observe the safety instructions contained in these instructions.
These instructions must be passed onto the end customer along with the unit in which the
compressor is installed.
GEA Bock GmbH
72636 Frickenhausen
GEA Bock GmbH
Benzstraße 7
72636 Frickenhausen
Germany
Telephone [phone]
Fax [phone]
[email protected]
www.gea.com
Manufacturer
Contact

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Contents Page
1 Safety 4
  1.1 Identicationofsafetyinstructions
  1.2 Qualicationsrequiredofpersonnel
1.3 General safety instructions
1.4 Intended use
2 Product description 6
2.1 Brief description
2.2 Name plate
2.3 Type key
3 Areas of application 8
3.1 Refrigerants
3.2 Oil charge
3.3 Limits of application
3.4 N and K versions
3.4.1 Limits of application R134a
3.4.2 Limits of application R407C
3.5 TK version
3.5.1 Limits of application R404A/R507
3.5.2 Limits of application R22
4Compressor assembly 11
4.1 Setting up
4.2 Maximum permissible inclination
4.3 V-belt drive
4.4 Main bearing load
4.5 Electromagnetic clutch assembly
4.6 Pipe connections
4.7 Pipes
4.8 Operating the shut-off valves
4.9 Operating mode of the lockable service connections
5 Commissioning 15
5.1 Preparations for start-up
5.2 Pressure strength test
5.3 Leak test
5.4 Evacuation
5.5 Refrigerant charge
5.6 Oil level check
5.7 Shaft seal
5.8 Shaft seal, emptying the oil reservoir
  5.9 Avoidingliquidshocks
6 Maintenance 18
6.1 Preparation
6.2 Work to be carried out
6.3 Recommended spare parts
6.4 Integrated decompression valves
6.5 Extract from the lubricants table
6.6 Decommissioning
7 Accessories 20
7.1 Capacity regulator
7.2 Thermi protection thermostat
8 Technical Data 21
9 Dimensions and Connections 22
 10 Installationcerticate 24
11 Service 25

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1.1 Identicationofsafetyinstructions:
DANGER! Indicates a dangerous situation which, if not avoided, will cause
immediate fatal or serious injury.
WARNING!
Indicates a dangerous situation which, if not
avoided, may cause fatal or serious injury.
CAUTION!
Indicates a dangerous situation which, if not
avoided, may cause fairly severe or minor injury.
ATTENTION! Indicates a situation which, if not
avoided, may cause property damage.
INFO! Important information or tips on simplifying work.
1|Safety
1.2 Qualicationsrequiredofpersonnel
WARNING! Inadequatelyqualiedpersonnelposestheriskofaccidents,the
 consequencebeingseriousorfatalinjury.Workoncompressorsis
 thereforereservedforpersonnelwiththequalicationslisted
 below:
• For example, a refrigeration technician, refrigeration mechatronic
engineer.
As well as professions with comparable training, which enables
personnel to assemble, install, maintain and repair refrigeration and
air-conditioning systems. Personnel must be capable of assessing the
work to be carried out and recognising any potential dangers.

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1|Safety
These assembly instructions describe the standard version of the FK50 manufactured by GEA. The
compressor is intended for use in refrigeration systems in compliance with the limits of application.
Onlytherefrigerantspeciedintheseinstructionsmaybeused.
Any other use of the compressor is prohibited!
The GEA refrigerating compressor named in the title is intended for installation in a machine
(within the EU according to the EU Directives 2006/42/EC Machinery Directive, 97/23/EC Pressure
EquipmentDirective).
Commissioning is permissible only if the compressor has been installed in accordance with these
assembly instructions and the entire system into which it is integrated has been inspected and
approved in accordance with legal regulations.
1.4 Intended use
1.3 General safety instructions
DANGER! • Refrigerating compressors are pressurised machines and as
such call for heightened caution and care in handling.
The maximum permissible overpressure must not be exceeded,
even for testing purposes.
WARNING! • Risk of burns! Depending on the operating conditions, surface
temperatures of over 60 °C on the discharge side or below 0 °C
on the suction side can be reached.

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2|Product description
Three different designs are available for various ranges of application:
> for air-conditioning the K Design
> for air-conditioning or normal cooling the N Design
> for deep freezing the TK Design
The differences lie mainly in the valve plate tooling which is adapted to each applica-
tion range where operational safety and efficiency are concerned.
Compact six cylinder compressor in W design.
Six capacity ranges.
Lightweight aluminum design.
Lubricating oil pump with oil pressure relief valve independent of rotational direction.
Variable arrangement of the shut-off valves.
Fig. 1
2.1 Brief description
Fig. 2
Valve plate
Cylinder cover
Shaft end
Shaft seal
Suction shut-off valve
Suction line valve
Oil pump
Dimension and connection values can be found in Chapter 9
Eyebolt
Leak oil trapping
device with oil
reservoir
Name plate
Eyebolt
Oil sight glass
Oil sightglass
Discharge shut-off valve
Leak oil drain hose

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2|Product description
/
FK 05 775 NX
1 Type designation
2 Displacement at 1450 rpm
3 LP: Max. permissible operating pressure
  (g)Lowpressureside
HP: Max. permissible operating pressure
  (g)Highpressureside
4 Machine number
5 Factory-lledoiltype
Fig. 3
2.2 Name plate (example)
2.3 Type key (example)
¹)K - specially for air-conditioning
N - specially for air-conditioning or normal cooling
TK - specially for deep freezing
²)X- Esteroilcharging(HFCrefrigerant,e.g.R134a,R407C)
Designs ¹)
Swept volume
Size
Ester oil charging ²)
Series
1
2
3
4
5
AT12345A029
19/28bar
Observe the limits of application
diagrams!
}
FKX50/775N
67,4
GEA Bock GmbH
72636 Frickenhausen, Germany

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3|Areas of application
ATTENTION! Compressor operation is possible within the limits of application
    showninthediagrams.Pleasenotethesignicanceofthe
shaded areas. The limits of application must be observed.
Thresholds should not be selected as design or continuous
operating points.
    -Max.permissibledischargeendtemperature:140°C
    -Max.permissibleambienttemperature:100°C
    -Max.permissibleswitchingfrequency:12x/h
    -Aminimumrunningtimeof2min.atequilibrium
(continuous operation) must be achieved.
Avoid continuous operation near the threshold. Should the
compressor happen to be used near the thresholds, we
recommend the use of a thermal protection thermostat
(Accessories, Chap. 7).
   Foroperationwithcapacityregulator:
- Continuous operation, when the capacity regulator is activated, is
not permissible and can cause damage to the compressor.
- The suction gas superheat temperature may need to be reduced or
set individually when operating near to the threshold.
- When the capacity regulator is activated, the gas velocity in the
systemcannotundercertaincircumstancesensurethatsufci-
ent oil is transported back to the compressor.
When operating in the vacuum range, there is a danger of air
entering on the suction side. This can cause chemical reactions,
a pressure rise in the condenser and an elevated compressed-
gas temperature. Prevent the ingress of air at all costs!
 Thecompressorsarefactory-lledwiththefollowingoiltype:
- for R134a, R404A/R507, R407C FUCHS Reniso Triton SE 55
- for R22 FUCHS Reniso SP 46
Compressorswithesteroilcharge(FUCHSRenisoTritonSE55)aremarkedwithanXinthetype
designation (e.g. FKX50/775N).
3.1 Refrigerants
• HFKW / HFC: R134a, R404A/R507, R407C
• (H)FCKW/(H)CFC: R22
3.2 Oil charge
3.3 Limits of application
INFO! Forrecharging,werecommendtheaboveoiltypes.Alternativesare:
see lubricants table, Chapter 6.5.

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3|Areas of application
Designforotherrangesonrequest
Max. permissible
operating pressure (g) high-
pressureside(HP):28bar
Max. permissible
operating pressure (g) high-
pressureside(HP):28bar
Unrestricted
application range
Unrestricted
application range
Reduced suction
gas temperature
Reduced suction
gas temperature
Evaporationtemperature(°C)
Evaporationtemperature(°C)
Condensingtemperature(°C)
Condensingtemperature(°C)
Suctiongassuperheat(K)
Suctiongassuperheat(K)
Suctiongastemperature(°C)
Suctiongastemperature(°C)
Fig. 4
Fig. 5
20
30
50
70
80
-20 -10 10
020 30 t (°C)
o
t (°C)
c
82
-30
40
60
90
t + 25 °C
oh
<
?
t
oh
20 K
R134a
20
30
50
-20 -10 10
020 t (°C)
o
t (°C)
c
61
-30
40
60
-25
<
?
toh 20 K
t + 25 °C
oh
R407C
3.4.1 Limits of application R134a (N and K versions)
3.4 N and K versions
Models available:
• FKX50/460 N • FKX50/555 N • FKX50/660 N • FKX50/775 N
• FKX50/460 K • FKX50/555 K • FKX50/660 K • FKX50/775 K
• FKX50/830 N • FKX50/980 N
• FKX50/830 K • FKX50/980 K
Permissible rotation speeds:
N Design: 500 – 3000 rpm (maxrotationspeed3500rpm)
K Design: 500 – 3500 rpm
3.4.2 Limits of application R407C (N and K versions)
Permissible rotation speeds:
N Design: 500 – 2600 rpm
K Design: 500 – 3500 rpm

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3|Areas of application
3.5 TK version
Models available:
•FK50/460 TK •FK50/555 TK •FK50/660 TK •FK50/775 TK
•FKX50/460 TK •FKX50/555 TK •FKX50/660 TK •FKX50/775 TK
3.5.1 Limits of application R404A/R507 (TK version)
3.5.2 Limits of application R22 (TK version)
Permissible rotation speeds:
TK design: 500 – 2600 rpm
Permissible rotation speeds:
TK design: 500 – 2600 rpm
FK
10
0
-10
-20
-30
-40
-50
20
30
40
50
60
70
t (°C)
o
t (°C)
c
Dtoh<20K
t +20°C
oh
58
-45
R404A/R507
R404A/R507 TK
t
c
t
0
toh
Dt
oh
Verdampfungstemperatur (°C)
Verflüssigungstemperatur (°C)
Sauggasüberhitzung (K)
Sauggastemperatur (°C)
Uneingeschränkter
Anwendungsbereich
reduzierte Sauggastemperatur
FK
R22
t
c
t
0
toh
Dt
oh
Verdampfungstemperatur (°C)
Verflüssigungstemperatur (°C)
Sauggasüberhitzung (K)
Sauggastemperatur (°C)
Uneingeschränkter
Anwendungsbereich
reduzierte Sauggastemperatur
R22 TK
10
0
-10
-20
-30
-40
-50
20
30
40
50
60
70
t (°C)
o
t (°C)
c
Dtoh<20K
t +25°C
oh
66
-45
Max. permissible
operating pressure (g) high-
pressureside(HP):28bar
Unrestricted
application range
Reduced suction gas tempera-
ture
Evaporationtemperature(°C)
Condensingtemperature(°C)
Suctiongassuperheat(K)
Suctiongastemperature(°C)
Fig. 6
R404A/R507
R22
Max. permissible
operating pressure (g) high-
pressureside(HP):28bar
Unrestricted
application range
Reduced suction gas tempera-
ture
Evaporationtemperature(°C)
Condensingtemperature(°C)
Suctiongassuperheat(K)
Suctiongastemperature(°C)
Designforotherrangesonrequest
Fig. 7

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4|Compressor assembly
4.1 Setting up
4.2 Maximum permissible inclination
Amax. 30°,
max. 2 minutes
amax. 15°,
continuous
operation
ATTENTION! Poor lubrication can damage the compressor. Respect the stated
values.
INFO! Newcompressorsarefactory-lledwithinertgas(3barnitrogen).
Leave this service charge in the compressor for as long as possible
and prevent the ingress of air.
Check the compressor for transport damage before
starting any work.
Fig. 8
 Transportandsuspensionunitonbotheyebolts(Fig.8).
 Fittings(e.g.pipeholders,additionalunitsetc.)onthecompressorarepermissibleonly
following consultation with GEA.
 Setuponanevensurfaceorframewithsufcientload-bearingcapacity.Useall4fastening
points.
Correct setup of the compressor and mounting of the belt drive are decisive for running comfort,
operating safety and the service life of the compressor.
WARNING! Movecompressorsonlywithhoiststhathaveadequateload-bearing
capacity.
AA
aa
AA
aa
Fig. 9

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4|Compressor assembly
 During operation with capacity controllers (Accessories, Chap. 7), the changing load can cause
increased running noises and belt drive vibrations.
4.3 V-belt drive
4.5 Electromagnetic clutch assembly
ATTENTION! Inappropriately designed belt drives, especially belt knocking or
excessive tensioning forces can cause compressor damage!
Make sure that the drive belt is designed correctly, e.g. by using
 tensionersandselectingthebeltproleandthebeltlength.
The following description applies for an electromagnetic clutch secured to a shaft.
To absorb the magnetic eld of the electromagnetic clutch, the front bearing ange has
asnugt148h8(seeFig.11).
Toconnectthemagneticeld,loosenthe4cheeseheadscrewsM8onthebearingange
(seeFig.11).
Slidethemagneticeldtoasnugtandre-attachusingthefourcheeseheadscrewsM8
(Fig.12).Screwtorque=34Nm.
Further assembly of the electromagnetic clutch according to the clutch manufacturer.
Fig. 11
Bearingange,front
Magneticeld
Fig. 12
148 h8
4.4 Main bearing load
To prevent the belt drive overloading the compressor main bearing,
ensure that:
The engagement force applied by the belt tension (centre of
shafttaper,seeFig.10)mustnotexceedFmax per.=2750N.
If the force engagement point shifts to the right (see Fig.10,
smallpoint),theforceFmax per. reduces as per the following
formula:
Fmax per.= 245 kNmm
(90 mm + L1[mm])
Fmax= 2750 N
Mbmax= 245kNmm
L
1
(mm)
Fig. 10

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4|Compressor assembly
4.7 Pipes
Pipes and system components must be clean and dry inside and free of scale, swarf and layers of
rust and phosphate. Only use air-tight parts.
Lay pipes correctly. Suitable vibration compensators must be provided to prevent pipes being
cracked and broken by severe vibrations.
Ensure a proper oil return.
Keep pressure losses to an absolute minimum.
The discharge and suction line valves have stepped internal
diameters, enabling the use of pipes with standard millimetre and
inch dimensions. The depth of pipe insertion will depend on the
dimension.
The connection diameters of the shut-off valves are designed for
maximum compressor output. Therequiredpipecross-section
must be matched to the capacity. The same applies for
non-return valves.
Fig. 13: Stepped
internal diameters
4.6 Pipe connections
4.8 Operating the shut-off valves
Before opening or closing the shut-off valve, release the valve spindle seal by approx. ¼ of a turn
counter-clockwise.
After activating the shut-off valve, re-tighten the adjustable valve spindle seal clockwise.
Fig. 14 Fig. 15
ATTENTION! Overheating can damage the valve.
Therefore, remove the pipe supports from the valve before
soldering.
Solder only using inert gas to inhibit oxidation products.
 Therequiredtighteningtorquefortheangeconnectionis60Nm.
Valve spindle seal
Release
Tighten

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4|Compressor assembly
4.9 Operating mode of the lockable service connections
Fig. 16
Fig. 17
Opening the shut-off valve
Spindle 1: turn to the left (counter-
clockwise)asfarasitwillgo.
—> Shut-off valve fully opened /
service connection 2 closed.
Openingtheserviceconnection(2):
Spindle 1: 1/2- 1 rotation to the right
—> Service connection 2 opened /
shut-off valve opened.
Connection 3 is provided for safety devices
and is not lockable.
1
1
3
3
2
2
Afteractivatingthespindle,generallytthespindleprotectioncapagainandtightenwith14-16Nm.
This serves as a second sealing feature during operation.

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5|Commissioning
5.1 Preparations for start-up
5.4 Evacuation
First evacuate the system and then includethe compressor in the evacuation process.
Relieve the compressor pressure.
Open the suction and discharge line valves.
Evacuate the suction and discharge pressure sides using the vacuum pump.
At the end of the evacuation process, the vacuum should be < 1.5 mbar when the pump is switched off.
 Repeattheprocessasoftenasisrequired.
INFO! To protect the compressor against inadmissible operating conditions,
high-pressure and low-pressure pressostats are mandatory on the
installation side.
The compressor has undergone trials in the factory and all functions have been tested. There are
therefore no special running-in instructions.
Check the compressor for transport damage!
5.3 Leak test
Carry out the leak test on the refrigerating plant in accordance with EN 378-2 or a corresponding
safety standard, while always observing the maximum permissible overpressure for the compressor.
DANGER Risk of bursting!
The compressor must only be pressurised using nitrogen (N2).
Never pressurise with oxygen or other gases!
The maximum permissible overpressure of the compressor must
not be exceeded at any time during the testing process (see name
plate data)! Do not mix any refrigerant with the nitrogen as this
could cause the ignition limit to shift into the critical range.
5.2 Pressure strength test
The compressor has been tested in the factory for pressure integrity. If however the entire system is
to be subjected to a pressure integrity test, this should be carried out in accordance with EN 378-2
or a corresponding safety standard without the inclusion of the compressor.

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5|Commissioning
CAUTION! Wear personal protective clothing such as goggles and protective
gloves!
Make sure that the suction and discharge line valves are open.
 Withthecompressorswitchedoff,addtheliquidrefrigerantdirectlytothecondenserorreceiver,
breaking the vacuum.
If the refrigerant needs topping up after starting the compressor, it can be topped up in vapour
formonthesuctionside,or,takingsuitableprecautions,alsoinliquidformattheinlettothe
evaporator.
After starting, check the compressor's oil level.
Drive motor in operating condition "High idle".
Compressor run time min. 10 minutes.
The system should have reached operating points.
 Checkoillevel.Astheinstallationlocationofthecompressorcandifferinpractice(inclinations),
it is recommended that the oil level is checked in both sightglasses. The oil level must be visible
in at least one sightglass.
ATTENTION! Avoidoverllingthesystemwithrefrigerant!
To avoid shifts in concentration, zeotropic refrigerant blends
(e.g. R407C) must always be added to the refrigerating plant in
     liquidform.
 Donotpourliquidrefrigerantthroughthesuctionlinevalveon
the compressor.
It is not permissible to mix additives with the oil and refrigerant.
5.5 Refrigerant charge
5.6 Oil level check
5.7 Shaft seal
ATTENTION! Failure to observe the following instructions can cause loss of
refrigerant and damage to the shaft seal!
INFO! The shaft seal seals and lubricates with oil. An oil leakage
of 0.05 ml per operating hour is therefore normal. This applies
particularly during the run-in phase (200 – 300 h).
Totrapandcollectleakedoil,theFK50isttedwithan
integrated leak oil trapping device with oil reservoir (P.6, Fig. 1).
ATTENTION! After a compressor is replaced, the oil level must be checked
again. If the level is too high, oil must be drained off (risk of oil
impact, reduced performance of the air-conditioning system).

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5|Commissioning
As changing the shaft seal involves opening the refrigerant
circuit, this is recommended only if the seal is losing
refrigerant. Replacing the shaft seal is described in the spare
part kit concerned.
Emptyingtheoilreservoir: The oil reservoir can be emptied
very simple without having to dismantle the clutch and/or
belt drive. It is recommended that this is done at the same
time as the air-conditioning maintenance and motor service.
To proceed, detach the oil hose from the bracket, remove the
sealing plug and drain the oil into a collecting vessel. After
emptying, reseal the oil hose and clamp it into the bracket.
Dispose of the used oil in accordance with national
regulations.
The compressor shaft is sealed to outside using a shaft seal. The sealing element rotates with the
shaft.
The following is especially important to ensuring fault-free operation:
The complete refrigerant circuit must be correctly executed and clean inside.
Heavy shocks and vibrations to the shaft as well as continuous cyclic operation are to be
avoided.
 Thesealingsurfacescansticktogetherduringprolongeddowntimes(e.g.winter).Therefore,run
the system every 4 weeks for 10 minutes.
5.8 Shaft seal, emptying the oil reservoir
5.9 Avoidingliquidshocks
ATTENTION! Slugging can damage the compressor and cause refrigerant
to leak.
Topreventliquidshocks:
The complete refrigeration plant must be correctly designed and executed.
The capacities of all components must be compatible (particularly evaporator and expansion
 valve).
Suction gas superheating at the evaporator output should be at least 7 – 10 K (check setting
 oftheexpansionvalve).
 Thesystemmustreachastateofequilibrium.
 Particularlyincriticalsystems(e.g.severalevaporatorpoints),suitablemeasures,e.g.
 useofliquidtraps,solenoidvalveintheliquidline,etc.arerecommended.
Fig. 18

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6.1 Preparation
6.2 Work to be carried out
6|Maintenance
FK50 / ... 460 N, TK
555 N, TK
660 N, TK
775 N, TK
830 N
980 N
460 K, 555 K
660 K, 775 K
830 K, 980 K
Designation Art. No. Art. No. Art. No.
Set of gaskets 80231 80089
Valve plate kit 80243 80244 08926
Set of shaft seals 80023
Oil SP 46, 1 litre 02279
Oil SE 55, 1 litre 02282
Oilchange:In principle, an oil change is not mandatory if the system is correctly manufactured
and operated. However, based on decades of experience we recommend that the following oil
change/service work is carried out:
 - Firstoilchangeduringtherstmaintenanceofthevehicle.
- Then after every 5,000 operating hours, though no more than 3 years, clean the oil strainer
at the same time. If necessary, also empty the oil reservoir at the shaft seal.
Annualchecks: Oil level, tightness of the compressor, running noise, pressures, temperatures,
function of auxiliary devices such as checking the capacity control.
The valves are fundamentally maintenance-free.
However, constant leakage can occur after repeated blowing off due to abnormal operating conditions.
This leads to reduced performance and increases the compressed gas temperature. In this case check
the valves and replace as necessary.
6.4 Integrated decompression valves
Only use genuine GEA spare parts!
6.3 Recommended spare parts
WARNING! Beforestartinganyworkonthecompressor:
Switch off the compressor and secure it to prevent a restart.
Relieve compressor of system pressure.
Preventairfrominltratingthesystem!
  Aftermaintenancehasbeenperformed:
Connect safety switch.
Evacuate compressor.
Release switch lock.

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6.6 Decommissioning
Close the shut-off valve on the compressor. Drain the refrigerant (it must not be discharged directly
into the environment) and dispose of it according to the regulations. When the compressor is
depressurised, undo the fastening screws of the shut-off valves. Remove the compressor using an
appropriate hoist. Dispose of the oil inside in accordance with the valid national regulations.
6|Maintenance
6.5 Extract from the lubricants table
The oil type charged as standard in the factory is marked on the name plate. This oil type should be
used as a preference. Alternatives are stated in the extract from our lubricants table below.
Refrigerants GEA standard oil types Recommended alternatives
HFC
(e.g. R134a, R407,
R404A)
Fuchs Reniso Triton SE 55
(seealsochap.6.3)
Fuchs SEZ 32/68/80
Esso/Mobil EAL Arctic 46
HCFC(e.g.R22) Fuchs Reniso SP 46
(seealsochap.6.3)
BP Energol LPT 46
Sunoco Suniso 3.5GS
Texaco Capella WF 46

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7|Accessories
7.1 Capacity regulation
FK50 / ... ... N + TK ... K
Designation Item No. Item No.
Special accessory 12 V 08703 08708
Special accessory 24 V 08704 08709
Foradescription,seetechnicalinformation"Capacityregulation"(ItemNo.09900)
Ifthecapacityregulatorisfactory-tted,itisintegratedintoanextra,dedicatedcylindercover.For
retrots,itissuppliedwiththecylindercover.Theregulatorclosesonecylinderbankatatime(capacity
regulationapprox.33%).Tworetrotkitsarerequiredforacapacityregulationofapprox.66%.
A screw-in option is provided for the sensor element on the hot gas side of the compressor
housing(seeChap.9).Connectthethermalprotectionthermostatinserieswiththecontrolline.
Technical Data:
Switching voltage max. : 24 V DC
Switching current max. : 2.5 A at 24 V DC
Switch-off temperature : 145 °C ± 5 K
Switch-on temperature : approx. 115 °C
7.2 Thermal protection thermostat (Item No. 07595)
ATTENTION! Capacity-regulated operation alters the gas speeds and pressure
ratiosoftherefrigeratingplant:Adjustthesuctionlineroutingand
dimensioning accordingly, do not set the control intervals too close and
do not let the system switch more than 12 times per hour (refriger-
atingplantmusthavereachedastateofequilibrium).Continuous
operation in the control stage is not recommended as the gas
velocity in the plant system under certain circumstances does not
guaranteesufcientoil return tothecompressorwith activated
capacity regulator for a compressor speed below 1200 - 1500 rpm.
We recommend switching to unregulated operation (100% capacity)
for at least 5 minutes per capacity-regulated operating hour. An
  assuredoilreturncanalsoberealisedbya100%capacityrequire-
ment after each compressor restart as otherwise the compressor
can also be shut down in the regulated operating time by the
thermostat.
 Electricalactuationofthesolenoidvalve:Normallyopen,(corre-
sponds to 100 % compressor capacity).
Cylinder covers for capacity regulation are marked with the
designation "CR" (Capacity Regulator).