Quincy Compressor QR-25 Series, Instruction Manual

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QR-25 Series Quincy Compressor
52201-105, May 2003 29 3501 Wismann Lane, Quincy IL - 62305-3116
Trouble Probable Cause
Excessive Vibration •Piping inadequately supported or tightened into a bind
(cont.) •Excessive discharge pressure
•Compressor feet may need to be leveled with shims
Excessive drive belt wear •Pulley/sheave out of alignment
•Belt too loose or too tight
•Belt slipping
•Pulley/sheave wobbling
•Pulley/sheave groove damaged or rough
•Incorrect belts
Low oil pressure •Oil pump direction reversed
•Oil sump strainer plugged
•Excessive leakage at crankshaft seals
•Low oil level
•Oil pump incorrectly assembled to the bearing carrier (“o”ring not
properly located between oil pump body & bearing carrier)
•Oil pressure adjusting screw not set properly
•Defective oil pressure gauge
•Plugged oil filter
Compressor loads •Air receiver too small
and unloads excessively •Compressor valves or unloaders defective
•Excessive system leakage
•Compressor operating at incorrect speed
•Unloader pilot differential set too close
•Pressure switch defective
Defective pressure switch •Moisture &/or oil buildup on the pressure switch diaphragm
•Ruptured diaphragm
•Burned contact points
•Plugged air passage from the receiver to the pressure switch
•Loose electrical connection
Excessive air pressure •Air pressure gauge inaccurate
in air receiver •Leaks in unloader piping system
•Defective compressor valve unloader
•Pilot valve or pressure switch set incorrectly or defective
•Pressure switch wired incorrectly
•Hydraulic valve or three way valve not functioning properly
•Tube to compressor unloader valve plugged
Excessive •Intercooler restricted or plugged
intercooler pressure •Compressor valves in second stage broken or not functioning properly
(Two stage models only) •Pilot valve or pressure switch set incorrectly or defective
•Pressure gauge defective
*Obsolete models