BOCK FK40 Seroes - Compressor Cutoff

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Compressor cutoff
Cutoff though low-
pressure switch
Compressor starts and stops again
Symptom
Suction pressure too low:
- Check the setting of the low pressure
switch
- Suction valve of the compressor closed
- Capacity of compressor too large
- Refrigerant deficiency
- Filter / dryer in the liquid line blocked
- Expansion valve not functioning properly
- Solenoid valve on the liquid line not
opening
Possible cause
- Adjust the switching points or replace
switch
- Open shut-off valve
- Check operating conditions
- Leak test / Add refrigerant
- Replace filter / dryer
- Check the setting of the valve
- Check the control / function
Remedy
Cutoff through high-
pressure switch
Condensing pressure too high
- Check the setting of the high-pressure
switch
- Pressure valve of the compressor closed
- Condenser fan not functioning
- Condenser dirty
- Excessive refrigerant filling
- Non-condensible gases in refrigerant
- Adjust the switching points or replace
switch
- Open shut-off valve
- Check the control / replace motor
- Cleaning of condenser
- Extract refrigerant to normal filling
- Extract refrigerant and evacuate the
refrigeration plant / refill refrigerant
Cutoff through heat-
protection thermostat
(accessory)
Discharge end temperatures is too high
- Operating limits of compressor
exceeded
- Suction gas overheating
- Cooling of the condenser insufficient
- Valve plate damage
- Internal safety valve has opened
- Adapt the operating conditions to the
operating range
- Check expansion valve / Check
insulation on the suction side
- Check fan motors / Clean the condenser
- Replace valve plate
- Replace safety valve
Check compressor and refrigeration
plant Determine and remove the
cause for the inadmissible high
pressure in the high-pressure side
®
Cutoff through control
thermostat
- Temperature over / below the desired
range
- Check operating points
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09608-09-03-DGbFEI