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The next thing I would do is disconnect the fan connection from the board. Set the voltmeter to measure ohms. You will find tons of videos on how to ohm test an electrical motor. This test will you 1. If you have a loose wire connection to the motor 2 if the windings have opened 3 if one of the windings has shorted to ground.
If it trips the breaker immediately, that you have a short to ground in the compressor or fan motor.
If it you let it sit for 30 minutes, and the fan magically comes on when you try to start it, then you are tripping the internals of that motor because the motor is running too hot. First thing to check if tripping the thermals is the capacitor.
Richard and Rhonda Entrekin
95 Newell, 390 Ex caretaker
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(06-23-2025, 11:00 AM)Richard Wrote: The next thing I would do is disconnect the fan connection from the board. Set the voltmeter to measure ohms. You will find tons of videos on how to ohm test an electrical motor. This test will you 1. If you have a loose wire connection to the motor 2 if the windings have opened 3 if one of the windings has shorted to ground.
If it trips the breaker immediately, that you have a short to ground in the compressor or fan motor.
If it you let it sit for 30 minutes, and the fan magically comes on when you try to start it, then you are tripping the internals of that motor because the motor is running too hot. First thing to check if tripping the thermals is the capacitor.
Which one is the fan??
Dennis White
1997 Newell Coach 454
Canfield OH
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There are many different ways to trouble shoot things, most of them work, my approach is a little different from Richards, I would follow the wires from the fan back to the board and see if there is 120 volts going to the fan motor, if the fan is off on thermal overload the motor will be so hot you will not be able to touch it, if you spin the motor and it starts running the capacitor is bad, if there is no power to the fan motor you could put 120 to it let it run and you will have ac until you can fix it, just let the motor run
John Kosir
712 2004 45-8
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(06-23-2025, 01:37 PM)johnkosir Wrote: There are many different ways to trouble shoot things, most of them work, my approach is a little different from Richards, I would follow the wires from the fan back to the board and see if there is 120 volts going to the fan motor, if the fan is off on thermal overload the motor will be so hot you will not be able to touch it, if you spin the motor and it starts running the capacitor is bad, if there is no power to the fan motor you could put 120 to it let it run and you will have ac until you can fix it, just let the motor run
I am going to follow the wires back to the board. There was red, white, and black. Plus 2 brown ones going to the capacitor. I had a spare new capacitor and that didn’t change anything.
When it happened it was only running for a couple minutes. It was running fine. I stepped on the entry step to walk out of the coach and it kicked off right then. Tripped the breaker and that was that.
Dennis White
1997 Newell Coach 454
Canfield OH
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That might be a 2 speed fan motor I would guess that white is common and red and black are low and high just a guess
Breakers that have tripped a lot can trip early
John Kosir
712 2004 45-8
(This post was last modified: 06-23-2025, 04:55 PM by
johnkosir.)
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(06-23-2025, 04:48 PM)johnkosir Wrote: That might be a 2 speed fan motor I would guess that white is common and red and black are low and high just a guess
Breakers that have tripped a lot can trip early
I think you’re right on the 2 speed. So I would need to check voltage at the board right?? If there is juice on the board the fan motor is bad??
Dennis White
1997 Newell Coach 454
Canfield OH
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If there is 120 volts at the board where the fan motor connects with the fan motor hooked up try to give the fan blade a quick push if the motor starts turning the cap is bad, I would put a clamp on amp meter around the wire and see if it is drawing any current, then I would try the other wire to see if the other speed worked.
John Kosir
712 2004 45-8
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(06-23-2025, 08:06 PM)johnkosir Wrote: If there is 120 volts at the board where the fan motor connects with the fan motor hooked up try to give the fan blade a quick push if the motor starts turning the cap is bad, I would put a clamp on amp meter around the wire and see if it is drawing any current, then I would try the other wire to see if the other speed worked.
I have juice 120 at the fan connection on the board. I guess that means fan motor is bad??
Dennis White
1997 Newell Coach 454
Canfield OH
Posts: 104
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If you have a clamp on amp meter see if it is drawing any current, I would try both low speed and high speed, if it is not drawing any current and you do not have a bad connection you have a bad motor
John Kosir
712 2004 45-8
