Probable Cause
Power cord not plugged in.
Motor/Pressure switch in
Motor thermal overload switch has tripped.
Fuse blown or circuit breaker has tripped.
Wrong gauge wire or length of extension cord.
Air tank pressure exceeds motor/pressure switch
"cut-in" pressure.
Pressure release valve on motor/pressure switch
has not unloaded pump head pressure.
Defective motor, motor capacitor, motor/pressure
switch, or check valve.
Symptom 2. When in the ON (1) position, motor runs continuously.
Probable Cause
Motor/Pressure switch does not shut off motor
when air compressor reaches "cut-out" pressure
and safety relief valve activates.
Air compressor is incorrectly sized.
Symptom 3. Air continues to leak at motor/pressure switch release valve after motor stops.
Probable Cause
The check valve is stuck open.
Symptom 4. Air continues to leak at motor/pressure switch release valve after motor is running.
Probable Cause
Defective motor/pressure switch.
Probable Cause
Possible defective safety relief valve.
Excessive air tank pressure.
Troubleshooting
Symptom 1. Motor will not run or restart.
OFF (0)
position.
Symptom 5. Air leaks from safety relief valve.
12
Remedy
Plug cord into grounded outlet.
Move switch to
ON (1)
Turn air compressor off, wait until motor is cool,
then check motor circuit breaker.
Replace fuse or reset circuit breaker.
Check for proper fuse amperage.
Check for low voltage conditions.
Disconnect any other electrical appliances from
circuit or operate air compressor on its own
branch circuit.
Check chart on page 10 for proper gauge wire
and cord length.
Motor will start automatically when air tank
pressure drops below "cut-in" pressure of
motor/pressure switch.
Bleed the line by moving the switch to the
OFF (0)
position.
Contact Senco Customer Service.
Remedy
Move the motor/pressure switch to the
position. If the motor doesn't shut off, unplug the
air compressor. If the electrical contacts are
welded together, replace the pressure switch.
Limit the air pressure to the capacity of the air
compressor. Either use a smaller tool or a larger
air compressor.
Remedy
Remove, clean, or replace.
Remedy
Replace.
Remedy
Operate safety relief valve manually by pulling on
ring. If it still leaks, it should be replaced.
Defective motor/pressure switch. Replace.
position.
OFF (0)