Compressor running but not fan.

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Old 10-10-17, 02:06 PM
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Compressor running but not fan.

I'll go out and spend $100 or whatever and fix this tomorrow unless there is something else I should check. Like maybe in addition to the fan there might be a problem with that switch in there or something? Although either way I should be getting some resistance right? Any combination I connect the three contacts the dial shoots to the end. That means dead right?
 
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Old 10-10-17, 02:17 PM
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It sounds like you're using an analog ohmmeter. If you are, and the needle moves significantly when you put the probes on the motor leads, you DO have resistance. If you had an open circuit, the needle wouldn't move. Can you post a picture of the meter with it connected to the motor terminals?
 
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Old 10-10-17, 04:48 PM
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Sounds like you may not have the meter set on the right range,start at the lowest and work up.
Geo
 
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Old 10-10-17, 05:03 PM
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Push the fan blade with a screwdriver and see if it starts, if it starts you need a capacitor, Be sure you have turned unit on.
 
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Old 10-11-17, 06:56 AM
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Thanks. First of all, the fan started working today so I closed it up for the time being, but this is the 2md time recently its been giving me worries so I'll keep an eye on it.

As far as the multi meter, yes, it's analog. Thus it starts at the top, or left side being 1k ohms, and when reading resistance moves right til a couple ohms depending on what I'm testing, or shoot straight up to zero. The thing I don't understand then is why it even moves to 0 if only either infinite (no movement) or some reading of resistance are what you'd expect it to return. Since it's currently working should it not have moved the dial to some number below zero ohms? Or is the actual resistance measured so small. Can that be when I've got 0 to one ohm covering the first centimeter of the bar?

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Last edited by PJmax; 10-11-17 at 09:02 AM. Reason: added pic for meter
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Old 10-11-17, 07:52 AM
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Oh really? So that's why it's been intermittent? That capacitor is dying?
 
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Old 10-11-17, 08:11 AM
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Your multimeter is set to the x1K ohms scale, meaning that all the meter readings are multiplied by 1000. So, the smallest reading you can get on that scale is about 200 ohms (first small "tick" mark). I would expect the motor winding resistance to be <50 ohms, so you would need to go to a x1 ohms scale to get an accurate reading. However, even on your current scale, you can easily tell whether you have an open winding. If the meter goes all the way to the right (or nearly there), you have resistance, meaning that you do not have an open winding.

If you're fan is intermittent, then it's very possible you have a bad capacitor as pugsl suggested. The capacitance may be much lower than the specified value and may be on the borderline of what it takes to start the fan. They are relatively inexpensive, so I would suggest that you replace it and see if that solves the problem.
 
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Old 10-15-17, 04:20 PM
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Thank you. Makes sense.
So it's doing it again. This time both fan and compressor I found off while the inside fan was blowing. An hour later I turn it back to test and it's working. What would this suggest the problem might be if not still the capacitor? seems like it turns on fine but can't hang or something.
 
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Old 10-15-17, 04:32 PM
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You might have a dual capacitor hat starts both fan and compressor. Did you try to start fan like I suggested?
 
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Old 10-15-17, 05:10 PM
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Since the fan and compressor are both not running..... you need to check whether or not you have the 24vac to the outside unit. It sounds like the fan stops running and then the compressor shuts down on overheat. This CANNOT be allowed to continue. It will damage the compressor.
 
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Old 10-15-17, 06:05 PM
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no, I guess it didn't occur to me that it would turn on at all as silent as it was anyway but I also thought the capacitor was just for getting it going, where in my case it gets going but one time the fan itself stopped, then this last time I found them both completely off, as far as I could hear. so I'll do it next time for sure. but let me know if it could be anything else. I just want to rule out as much as possible before I start breaking things as I tend to do lol. Thanks!
 
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Old 10-15-17, 06:09 PM
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thanks. okay, so next time test that while the system is on and outdoor fan/compressor halted before it cools down again or something? or is there something I can test while it's currently working? intermittent problems. my favorite. |:
 
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