GEA FK40/390 K Maintenance Manual page 14

6 I Fault diagnosis
Abnormal running noise from compressor
Problem
Fixation of compressor is loose
Liquid shock
Capacity regulator (accessory)
Electromagnetic coupling slipping - see also p. 14 „Malfunction of electromag-
V belt drive,
increased noise generation
Malfunction of the electromagnetic coupling
Problem
Coupling not switching
Coupling slipping too long, get-
ting hot, smoking and squeaking
Coupling not separating
14
Possible cause
- Screwed connections have become loose
- Securing elements for screwed connections
missing
- Vibration metals defective
- Liquid refrigerant reaching the compressor
- Oil shocks because of too much oil
- Switching on and off constantly / oscillating
- Defective
netic coupling"
- Belts vibrating excessively
- Incorrect alignment of compressor and motor
Possible cause
- No voltage applied
- Voltage too low
- Driving power too high
- Rotor rubbing at the magnetic field
- Voltage still being applied to the magnet
- Coupling is stuck
- Coupling overloaded,
Armature disc is deformed
Remedy
- Tighten the screwed connections and secure
them anew
- Replace vibrations metals
- Adjust / check expansion valve
Check refrigerant filling
Check evaporator fan
- Icing-up of the evaporator
- Check oil level
Check the dimensioning of pipes (gas velocity)
Replace worn piston rings
- Check the control
- Replace capacity regulator valve
- Checking
- Check belt tension
Use tensioning roller / guidance roller
- Check alignment and adjust anew
Remedy
- Apply voltage and check
- Keep the voltage at 12 or 24 Volts (check
vehicle network)
- Check operating conditions
- Check the seating of the magnet possibly
to high belt tension
- Check switch / relay
- Disconnect the armature disc from the rotor
mechanically
- Install new rotor ans armature disc