12
TROUBLESHOOTING
Symptom 1. Motor will not run or restart.
Symptom 2. When in the "ON" position, motor runs continuously.
Symptom 3. Air continues to leak at motor/pressure switch release valve after motor stops.
Power cord not plugged in.
Motor/Pressure switch in "OFF" position.
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.
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.
PROBABLE CAUSE
Defective pilot valve, the check valve is stuck open.
REMEDY
Move the motor/pressure switch to the "OFF" 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.
Plug cord into grounded outlet.
Move switch to "ON" position.
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" position.
Contact Senco Customer Service.
