by Don
(Spokane, WA)
It’s a CENTRAL PNEUMATIC AIR COMPRESSOR 2 HP-8 GALLON model 40400
I need to know what to do when the compressor doesn’t start?
Hello Don. Nice to hear from you.
A few questions and observations:
-are you sure you are getting power?
-if you have an on/off button, is it set to on?
-do you have a re-set button on your motor? If so, push it.
-is the pressure in the tank below the cut-in pressure of your pressure switch?
These are just a few of the things to check.

Won’t start
I have power with and without an extension cord. On switch is on. The reset button won’t start the motor.
I drained the tank from the screw below to make sure there is no humidity inside. Last use I had to drain the tank just to get it to start.
In order for the compressor to start, electricity must flow through the pressure switch to the motor.
If all conditions are “calling for power”, and the compressor motor doesn’t start, and you have made all the checks to make sure there isn’t another issue preventing the start, then the next check is to be sure that power is actually getting through the switch to the motor, and you need to look at the pressure switch at this point.
If power isn’t flowing across the switch with the tank empty of air, it’s likely the switch.
If power is flowing across the switch, and the compressor is cold, make sure power is getting across the reset switch. They sometimes fail.
Let us know what you’ve found, will you?
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