Senco PC0968N - Troubleshooting

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