Product Manual
Table Of Contents
46  2022 2096 26 
Instruction book 
Condition  
Fault 
High discharge temperature 
Compressor valve assemblies defective 
Discharge pressure too high 
Inadequate ventilation or hot air recirculating 
Cooling surfaces of compressor or intercooler excessively dirty 
Ambient temperature too high 
Scored or excessively worn cylinder walls 
Compressor knocks 
Head clearance insufficient 
Piston loose in cylinder bore, cylinder bore worn, piston or piston rings worn 
Worn rods or main bearing 
Wrong pressure setting, discharge pressure excessive 
Crankcase lubrication inadequate 
Loose pulley/sheave 
Excessive oil consumption  
Compressor runs unloaded too long 
Worn piston rings 
Restricted intake system 
Compressor running too hot 
Breather valve not functioning properly 
Oil level in crankcase too high 
Oil viscosity wrong for the application 
Connecting rod out of alignment, bent or twisted 
Leaking oil seal 
Piston rings not seated (allow 100 hours for seating) 
Wrong oil (may be a detergent oil with a tendency to foam) 
Inferior grade of oil 
Excessive current draw  
(To determine maximum 
amperage allowed, multiply 
the FLA on the motor 
nameplate by the service 
factor.) 
CAUTION !  
Motor surface temperature 
normally exceeds 170° F.
Low voltage (must be within 10% of nameplate voltage) 
Loose electrical connection 
Wire size too small 
Incorrect oil 
Discharge pressure too high 
Intercooler plugging 
Bearings tight or seizing 
No crankshaft endplay 
Motor sized incorrectly 
Motor defective 
Drive belts too tight 
Failure to start  
CAUTION! 
Overload relays are 
designed to protect the 
motor from damage due to 
motor overload. If the 
overload relay trips 
persistently, DO NOT 
CONTINUE TO PUSH THE 
RESET BUTTON! Contact 
your local Quincy 
distributor for assistance. 
Power not on 
Blown circuit fuse 
Overload relay tripped 
Low voltage 
Faulty start switch 
Power failure 
Pressure switch incorrectly adjusted or faulty 
Loose or broken wire 
Motor defective 
Compressor seized 
Motor stalls  
Motor overloaded  










