070.250-IOM (APR 11)
Page 22
408 MM ROTARY SCREW COMPRESSOR
MAINTENANCE
TROUBLESHOOTING THE OIL PUMP AND SYSTEM
SYMPTOM
PROBABLE CAUSES and CORRECTIONS
PUMP WILL NOT PRODUCE
ENOUGH OIL PRESSURE AT
START-UP
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
OFF WHEN COMPRESSOR
STARTS
Main oil injection throttling valve too wide open or oil pressure regulating valve
improperly adjusted.
Readjust both valves.
NOISE and VIBRATION
Pump strainer blocked.
Clean.
Pump worn out.
Repair or replace.
OIL PRESSURE DROPS AS HEAD
PRESSURE INCREASES
Normal behavior. Set main oil injection and oil pressure for maximum head pressure
condition.
MAIN UNIT 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.