16
17
TROUBLESHOOTING
Problem
Possible Cause
Solution
Compressor will not run
Loss of power or overheating
No electrical power
Blown shop/house fuse
Shop/house breaker open
Thermal overload open
Pressure switch bad
Tank is full of air
Check for proper use of extension
cord
Check to be sure unit is plugged in
Check fuse/breaker or motor over-
load
Replace shop/house blown fuse
Reset shop/house breaker, determin-
ing why problem happened
Motor will restart when cool
Replace pressure switch
Compressor will turn on when tank
pressure drops to cut-in pressure
Motor hums but cannot run or runs
slowly
Low voltage
Wrong gauge wire or length of exten-
sion cord
Shorted or open motor winding
Defective check valve or unloader
Check with voltmeter
Check for proper gauge wire and
cord length
Take compressor to service center
Take compressor to service center
Fuses blow/circuit breaker trips
repeatedly
Incorrect size fuse, circuit overload
Wrong gauge wire or length of exten-
sion cord
Defective check valve or under loader
Check for proper fuse, use time-
delay fuse, disconnect other electri-
cal appliances from circuit or operate
compressor on its own branch circuit
Check for proper gauge wire and
cord length
Take compressor to service center
Thermal overload protector cuts out
repeatedly
Low voltage
Lack of proper ventilation/room tem-
perature too high
Wrong gauge wire or length of exten-
sion cord
Check with voltmeter
Move compressor to well-ventilated
area
Check for proper gauge wire and
cord length
Air receiver pressure drops when
compressor shuts off
Loose connections (fittings, tubing,
etc.)
Loose drain valve
Check valve leaking
Check all connections with soap and
water solution and tighten
Tighten drain valve
Take compressor to service center
DANGER:
Do not disassemble check valve
with air in tank — bleed tank.
Excessive moisture in discharge air
Excessive water in air tank
High humidity
Drain tank
Move to area of less humidity; use air
line filter
Compressor runs continuously
Defective pressure switch
Excessive air usage
Take compressor to service center
Decrease air usage; compressor not
large enough for tool’s requirement
Compressor vibrates
Loose mounting bolts
Tighten mounting bolts
Air output lower than normal
Broken inlet valves
Connections leaking
Take compressor to service center
Tighten connections
