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  #21  
Old 10-31-2008, 05:11 PM
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TommyA TommyA is offline
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Ok here We have some pictures to give a better description of what I have. The centrifugal switch contacts look good and ohm out correct. In picture two you can see the back side of the breaker and it ohms out correct. In order to run the motor on the run capacitor I would need to spin the shaft fast enough to spin the centrifugal out and change the contacts. That isn't going to happen.

I don't have a way of checking the start capacitor other than calling a friend over. So I'm betting that is the problem.

I went in the breaker panel to see how it was wired at the breaker. White and black both come of the breaker on separate connections on the same breaker. Each side measures 120v same as the connections to the motor. I measured the connections on the motor with the pressure switch on and off and was able to get voltage with the switch in the correct throw so the Pressure switch is working. There are three wires White to ground= 120v, black to ground = 120v and green= ground. Between the black and white there isn't a reading.

I have reset all circuit breakers at the first sign of trouble and have continued to reset each at each stage of troubleshooting. I'm not brave enough to disconnect the motor wiring with power on.

In my wiring experience I have understood that some 220 wiring is actually two 120v lines connected and combined in the actual motor or appliance. If I misunderstand this please correct me.
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  #22  
Old 10-31-2008, 05:31 PM
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From one line to ground doesn't matter in this case, it is the voltage BETWEEN the two lines that needs to be at 240. If not, you only have one line supplying power. Check the contacts at the switch, check your panel to see if there are two single breakers that one has tripped. (They should be physically connected so that one trips, the other should, but doesn't always happen.)

Like has been mentioned, it sounds as the pressure switch isn't contacting on one side.
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  #23  
Old 10-31-2008, 05:31 PM
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Quote:
Originally Posted by TommyA View Post
Between the black and white there isn't a reading.
Bingo.
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  #24  
Old 10-31-2008, 05:53 PM
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I'm going to wire the breaker direcly to the motor to check this.
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  #25  
Old 10-31-2008, 06:06 PM
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Why don't you check the voltage going into the switch at the switch ?
I would not rule out a bad wire from vibration.
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  #26  
Old 10-31-2008, 06:13 PM
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Stupid Switch!
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  #27  
Old 10-31-2008, 07:15 PM
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  #28  
Old 10-31-2008, 07:52 PM
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I now know how a compressor pressure switch works. I should because I have all the parts laid out on the work bench. Another one of those you can take it apart but you can't put it back together type lessons.

After connecting the motor direct I checked between the two power connections on the motor and read 240v. Unfortunately this is the way I learn best by digging into the problem until I see and understand every aspect of the system.

Thanks for all the directing.
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  #29  
Old 10-31-2008, 10:10 PM
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14 years is not bad duty for a pressure switch, not too bad.

Are points burnt?
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  #30  
Old 11-01-2008, 11:41 AM
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Points were burnt together on one side of one of the legs. It caused the other side to be a such an angle it wouldn't make contact when the switch closed. Power was back feeding through the motor to show power each side of the switch.
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