Possible Fan Motor failure?


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Old 07-15-18, 03:01 PM
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Possible Fan Motor failure?

Right on queue for the hot weather, my moms A/C has gone out at her home.

After researching, it sounded like it was a capacitor issue so I ordered a new one and installed it. Turned everything back on and there is absolutely no noise coming from the fan or compressor or condenser? outside. I have tried turning the blades of the fan with a stick and nothing helps.

I opened the contactor and pushed in on it and again no noise or sounds. The thermostat clicks inside, and says it is cooling, the blower fan inside is also working but nothing is kicking the a/c on.

My next job is replacing the contactor switch but that will not be here until Tuesday and it is so miserable in the house!

Googling this issue brought me to this post which sounds similar to what I am experiencing.

New contactor and capacitor a/c not working.

With no updates at the end, I assume that ended up working? Do you guys have anything else to try?
 
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Old 07-15-18, 03:20 PM
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Hi, do you have a voltmeter? before you replace the contractor you must get 24 volts to the contactor coil , also check to be sure you have 240 volts at the disconnect by the condenser, if nothing started when you pushed the contactor in (not a really good idea) sounds like you do not have 240 volts, top terminals on the disconnect should have 240 volts then work your way to the contactor.
Geo
 
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Old 07-15-18, 04:03 PM
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I have a very cheap multimeter, my fluke one is at home but i will bring it out next time.

When i touch the input, i am getting voltage but only on the right side of the contactor. The left side with the "switch" does not have any voltage going through it.
 
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Old 07-15-18, 04:45 PM
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You need 24vac present when measured to both sides of the contactor coil.
It is very possible that your condensate system has caused an interruption in condenser power.
 
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Old 07-15-18, 05:18 PM
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Pete , good point on the float switch inside the air handler,but he said nothing happened when he pushed the contactor in by hand.
What voltage did have on the contactor, did you check at the disconnect?
Geo
 
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Old 07-15-18, 05:40 PM
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If the disconnect you're talking about is the one on the side of the condenser, no I was not able to check that today.

The multimeter was set to V, and 300 AC. The voltage was only measuring around 75 so either I was on the wrong setting or I need to bring my fluke out there.

The soonest I can get back out there is Tuesday and the contactor should be there by then. Would really love to either order a part or get this figured out to beat this heat. I would hate to go back out again on tuesday and not have it solved. Hvac companies are a month out with appointments
 
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Old 07-15-18, 06:08 PM
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That setting should be fine, start at the service panel and be sure there are no breakers tripped, then check the top terminals in the disconnect on the condenser, are there fuses in there?
Geo
 
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Old 07-17-18, 07:26 PM
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No breakers tripped.

Installed new contactor, and same thing, no noise, nothing. dead silence.

Checked the Condenser where the wires run into it and i cant see much, it does not have a fuse though.

Took some pictures with the multimeter
 
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Old 07-17-18, 10:31 PM
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When measuring across L1 and L2 (red and black incoming line wires) you should measure 240vac. You are measuring about 70vac. You will need to check next at the disconnect for the condenser. You need to measure 240vac across the two hot wires. If it's still low..... you will need to go to the panel and check the two terminals on the breaker.

Have you tried PUSHING the breaker to off and then turning back on. Many breakers must be pushed hard to the off position to reset it. A breakers handle may not always move if the breaker has tripped.
 
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Old 07-18-18, 04:32 AM
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That meter appears to be rated for 100 VAC, you need something rated at at least 300 VAC.
Geo
 
 

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