How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask AssuredElectrical Your Own Question
AssuredElectrical
AssuredElectrical, Master Electrician
Category: Electrical
Satisfied Customers: 4241
Experience:  Contractor-42+ Years in the ElectricalTrade
53189252
Type Your Electrical Question Here...
AssuredElectrical is online now
A new question is answered every 9 seconds

I have craftsman professional 240 volt 15 amp 2 strange compressor.

This answer was rated:

I have craftsman professional 240 volt 15 amp 2 strange compressor. Have black, white, and green wires. I hooked up black and white to breaker and green to ground, but compressor will not turn on. Can you help me please

AssuredElectrical :

Welcome. My name is XXXXX XXXXX would be glad to assist.

AssuredElectrical :

You have a double pole 15 or 20 amp breaker connected?

Customer:

15

AssuredElectrical :

ok, and it is a double pole, correct?

Customer:

correct

AssuredElectrical :

ok, can you turn off power, then look on the compressor. You will find a pressure switch that the power cord is connected to. Remove the cover and look at the connections.

AssuredElectrical :

The pressure
switch automatically starts the motor
when the air tank pressure drops
below the factory set "cut-in"
pressure. It stops the motor when the
air tank pressure reaches the factory
set "cut-out" pressure.

AssuredElectrical :

It could be the switch is stuck open

Customer:

ok done

AssuredElectrical :

The manual also shows an on off switch on that unit

AssuredElectrical :

actually says On-Off-Auto in the manual I have

Customer:

the unitt is urned off

AssuredElectrical :

Do you have a voltage tester?

Customer:

yes

AssuredElectrical :

how many terminals in the pressure switch? 2 or 4?

Customer:

4 2 black and 2 white

AssuredElectrical :

ok, use the tester and turn on power. Measure the white and black on the cord at the 2 terminals and read the voltage, then read the other 2 outgoing wires on their terminals, see if the voltage is 240 volts on both sets

Customer:

my voltage meter is not working

AssuredElectrical :

Ok

AssuredElectrical :

Does yours have the ON OFF AUTO switch on the compressor?

Customer:

yes

AssuredElectrical :

Ok, and you tried ON and Auto and neither works?

Customer:

yes

AssuredElectrical :

Ok, put it in Auto mode and tap on the pressure switch. Not real hard, but hit it with a screwdriver to see if it latches in

AssuredElectrical :

The are spring loaded and it may be stuck

Customer:

ok hit it nothing

AssuredElectrical :

Ok, turn off power and see if you can remove the cover on the On Off Auto switch, look for a loose wire. If nothing is loose, need a tester to troubleshoot

Customer:

k all wires are tight

AssuredElectrical :

Ok, need a tester to go any further.

Customer:

k thank you

AssuredElectrical :

Have to test the wiring, from the breaker to the switch, from the switch to the pressure switch and from the pressure switch to the motor

AssuredElectrical :

Somewhere it appears one of them is bad and not making contact or possibly wire loos in motor connections

AssuredElectrical :

see if you can open the cover where the motor is wired , should be a cover ob=ver the wiring compartment

Customer:

ok thank you for the help

AssuredElectrical :

ok, get the tester and come back and let me know, we can work from there

Customer:

ok thank you

AssuredElectrical :

you are welcome

AssuredElectrical and other Electrical Specialists are ready to help you