Frick RWF, Installation Operation & Maintenance

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RWF ROTARY SCREW COMPRESSOR UNITS
MAINTENANCE
S70-600 IOM
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TROUBLESHOOTING THE DEMAND PUMP SYSTEM
SYMPTOM PROBABLE CAUSES and CORRECTIONS
PUMP WILL NOT PRODUCE Check pump rotation.
ENOUGH OIL PRESSURE
TO START COMPRESSOR
Check that service valves are open.
Filter cartridges may be blocked. Check PSID across filters.
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 Main oil injection throttling valve too wide open or oil pressure
OFF WHEN COMPRESSOR STARTS regulating valve improperly adjusted. Readjust both valves.
RESULTS IN COMPRESSOR
DIFFERENTIAL ALARM
OIL PRESSURE FLUCTUATES Liquid injection overfeeding or refrigerant flood back from system. Make
necessary adjustments or corrections
NOISE and VIBRATION Pump strainer blocked. Clean.
Liquid refrigerant overfeed. Adjust liquid injection.
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 Normal behavior. Set main oil injection and oil pressure for maximum head
PRESSURE INCREASES 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 filter outlet is partially closed. Open valves fully.