Furnace blowing cold air


  #1  
Old 11-08-16, 06:42 AM
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Furnace blowing cold air

Cold air blown out and I did the following trying to troubleshoot the problem:
1. LED flashes 4 times indicating open limit switch
2. Jump limit switch and it started to have hot air
3. After a while it no longer blows out hot air
4. turn the power off, wait for 15 minutes and turn it back on, the LED flashes out 4 times again and no ignition sequence

Thanks for helping.
 
  #2  
Old 11-08-16, 08:29 AM
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Please start a new thread for your problem.
Never jump a safety like that. It can be very dangerous. Use a meter.
 
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Old 11-08-16, 05:01 PM
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The most common reason for a limit switch to open is a plugged furnace filter.


Return air vent covered over or too many warm air vents closed can cause that problem.

Collapsed ductwork, insulation inside the ductwork torn away and plugging thing up, fan wheel plugged with dust and dirt, fan motor not coming up to speed due to lack of lubrication are other causes.
 
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Old 11-08-16, 07:45 PM
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Please start a new thread for your problem.
Why roughneck77 ? .....................................................
 
  #5  
Old 11-08-16, 09:15 PM
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The OP hijacked an old thread with his question.
I reported it and a staff member moved it to its own thread.
 
 

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