Compressor Fan works sometimes and does not work sometimes

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  #1  
Old 06-04-11, 02:39 PM
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Compressor Fan does not work sometimes

The AC works perfectly most of the time, however, sometimes when the AC is on, the compressor fan is not running, in which case the AC keeps working for several hours.
What should I do about that?
Thanks.
 
  #2  
Old 06-04-11, 03:16 PM
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Use a stick push the fan to see if you can start the fan. If not then turn the unit off, do not let the compressor run without the fan. If you can push it to start, replace capacitor.
 
  #3  
Old 06-05-11, 10:50 AM
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thanks

thank you so much.
I will definitely try when that happens next time.
 
  #4  
Old 06-05-11, 12:54 PM
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That situation is extremely hard on the compressor.

The head pressure will skyrocket, & the compressor & its oil will get extremely hot.
That could cause the oil to breakdown!

That could cause premature compressor failure.

Every condenser should have a high pressure switch installed,to protect the compressor.
 
  #5  
Old 06-05-11, 08:37 PM
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It looks like the inside fan ( the air blower) is ocassionally on and on after the temperature reaching the set point.But mos of the time, the air blower turned off when the set point reached.
 
  #6  
Old 06-06-11, 01:33 PM
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When you say compressor fan, you mean the fan on the top (usually) of the outdoor unit, right? This is actually the condensor fan that helps remove heat from the condensor coils. You definitely need this running to cool the refrigerant the compressor is passing to it.

Is it still humming? Is it trying to spin?

***DANGEROUS! BE CAREFUL!***

what you could try and do is take the cover off of it and when it's on, but not spinning, take a broom handle and see if you can push start it...

***I HOPE YOU WERE CAREFUL***

If it is humming, and you can push start it then something in the motor is seizing up and you've probably gotta replace the fan motor... you may find it runs pretty good after doing this though as well... not something you want to keep doing.

Otherwise, if it's not humming or trying to spin then you may have a short in the wiring, kill power to the unit and look for a break in the insulation of the wiring, or a loose connection.


Best of luck,
Sam
 
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Old 06-06-11, 01:36 PM
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Somehow I missed those previous replies... sorry about that, but now I'm confused... is it the air blower inside your house or the condensor fan outside your house... or you have 2 seperate problems?

Sam
 
  #8  
Old 06-06-11, 09:27 PM
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Sorry about the confusion. Here is the situation: sometimes when AC is on(by which I mean the inside fans are on), the outside fan is not on, and it looks like(I am not sure) the compressor is not working either because I cannot hear any noise from it. In that case, the inside fans cannot stop working.
Hopefully I made myself clear.
Thanks for your replies.
 
  #9  
Old 06-06-11, 09:33 PM
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2 fans in the system....outside unit fan and indoor blower outside unit also contains a compressor.

SO.........What is your thermostat set on? fan Auto or ON? If the outdoor unit is not coming on at all during a call for cooling then you need to check for 24V to contactor on the coil circuit.
 
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Old 06-06-11, 09:43 PM
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fan is 'auto'.
most of the time it works perfectly, the house is cooled and AC(both of the inside fan and outside unit) works every several minutes to keep the house cool. however, sometimes only indoor blower is on and it does not stop even the temp is reached.
 
  #11  
Old 06-07-11, 04:22 AM
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relay in indoor unit may be sticking; Hard to say.... you would have to do some voltage checks to verify while acting up
 
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Old 06-08-11, 09:11 PM
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Can anybody tell me how do I know if the compressor is working or not? Then I can know the compressor is working without fan running or only inside fans are working.
Thanks.
 
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Old 06-08-11, 09:39 PM
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measure the amp draw on the common wire of the compressor to verify if compressor is working or not.
 
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Old 06-09-11, 07:09 AM
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If U don't have an amp-probe, feel the refrigerant lines; also listen, as U should be able to hear the compressor running.

U said U couldn't hear the compressor running...
 
  #15  
Old 06-10-11, 11:59 AM
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pushing the outside fan by a stick did not work.
I think I made mistake in previous message, the compressor is making noise.
Is it a bad news if the compressor is working without outside fan running?
Thanks.
 

Last edited by shuangseyun; 06-10-11 at 12:36 PM.
  #16  
Old 06-10-11, 02:11 PM
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change your capacitor. if the fan and compressor are not running and your contactor is pulled in providing power to the unit, its your cap.
 
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Old 06-10-11, 04:19 PM
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DO NOT run the condenser with the fan NOT running!

That is extremely hard on the compressor!
 
  #18  
Old 06-13-11, 11:01 PM
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It seems the situation is this: the compressor and compressor fan work during a call for cooling, then when the temperature is reached, compressor fan stop working, but the air blower keep working; and when the temperature goes up and the house needs to be cooled, the compressor fan works again.
So during a call for cooling, the compressor fan always works. However, when the temperature is reached, the compressor fan always stops working, sometimes the air blower stops working too, but sometimes it does not(I do not know if the compressor is working or not though).
Thanks in advance.
 
  #19  
Old 06-14-11, 04:33 AM
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sound like a relay is sticking for the indoor blower.
 
  #20  
Old 06-14-11, 10:40 PM
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Is there any easy way to fix it then?
Thank you.
 
  #21  
Old 06-15-11, 05:40 AM
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replace the control board in furnace if there is one or they may be a fan relay in the furnace that can be replaced.
 
  #22  
Old 06-15-11, 10:04 PM
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Thank you so much.
It is really helpful.
 
 

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