RWH ROTARY SCREW COMPRESSOR UNITS
MAINTENANCE
070.620-IOM (DEC 12)
Page 37
TROUBLESHOOTING THE RWH COMPRESSOR
SYMPTOM PROBABLE CAUSES and CORRECTIONS
EXCESSIVE NOISE and VIBRATION Main oil injection valve may be closed. Open valve.
Main oil injection valve may be open too far. Adjust.
Bearing damage or excessive wear. Contact Frick Factor or Frick service.
Slide valve/slide stop out of calibration (over- or undercompression)
Coupling loose on shaft. Tighten coupling. Replace if damaged.
If motor or compressor have been reinstalled, check that installation done according to 070.660-SM
Refrigerant ood-back. Correct system problem.
SLIDE VALVE and/or SLIDE STOP
WILL NOT MOVE
4-way hydraulic control valve failed. Repair or replace.
Control or full-lube pump is not running. Repair or replace.
Slide stop indicator rod stuck. Contact Frick Factor or Frick service for assistance.
Check both S.V. and S.S. feedback devices for wiring and resistance.
Compressor must be running with sufcient oil pressure.
Unloader piston stuck. Contact Frick Factor or Frick service for assistance.
Slipper seals worn out or damaged. Contact Frick Factor or Frick service for assistance.
TROUBLESHOOTING THE PUMP SYSTEM
SYMPTOM PROBABLE CAUSES and CORRECTIONS
PUMP WILL NOT PRODUCE
ENOUGH OIL PRESSURE
TO START COMPRESSOR
Check pump rotation.
Check that service valves are open.
Filter cartridges may be blocked. Check PSID across lters.
Strainer may be blocked. Clean.
Oil pressure regulator set too low or stuck open. Readjust or repair.
Pump worn out. Repair or replace.
OIL PRESSURE RAPIDLY DROPS
OFF WHEN COMPRESSOR STARTS
RESULTS IN COMPRESSOR
DIFFERENTIAL ALARM
Main oil injection throttling valve too wide open or oil pressure
regulating valve improperly adjusted. Readjust both valves.
OIL PRESSURE FLUCTUATES Liquid injection overfeeding or refrigerant ood back from system. Make
necessary adjustments or correc tions
NOISE and VIBRATION Pump strainer blocked. Clean.
Liquid refrigerant overfeed. Adjust liquid injec tion.
Pump worn out. Repair or replace.
GREASE LEAKS FROM VENT PORT Normal leakage which will cease after initial operation. Black oil leaking
IN THE SIDE OF THE PUMP BODY from this vent indicates oil seal wear or failure. If leakage exceeds normal allowable rate of 7
drops per minute, replace seal.
OIL PRESSURE DROPS AS HEAD
PRESSURE INCREASES
Normal behavior. Set main oil injection and oil pressure for maximum head
pressure condition.
MAIN FILTER PSID IS TOO HIGH Filters clogged with dirt. Replace.
Oil is too cold. Allow oil to warm up and check again.
Service valve on lter outlet is partially closed. Open valves fully.
NOTICE
Troubleshooting the compressor is limited to identifying the probable cause. If a mechanical problem is suspected contact
the Service Department. DO NOT ATTEMPT TO DISASSEMBLE THE COMPRESSOR.
To Next Page
Loading...
Need help?
General