3 amp fuse blown


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Old 06-23-15, 05:44 PM
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3 amp fuse blown

I have an ac Model EN15B. 3 amp fuse blows when call for ac. Have removed the lv wires from the contacter and it still blows. I can't see any visible signs of a short. Fuse did not blow on call for heat. How should I isolate wires and ohm them out?
Thanks
 
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Old 06-23-15, 05:55 PM
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A. I would inspect for damage to the control wires outside near the condenser



B. then look for any damaged wiring to the pressure switches in the condenser.



C. Isolate the 2 condenser wires from the system at the furnace.

D. Isolate the 2 condenser wires where they enter the condenser outside.

A 24VAC LED light can be used instead of popping fuses for testing if you have one.
 
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Old 06-23-15, 05:57 PM
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If nothing else has changed,and the fuse is on a control board remove the wire from the Y on the control board and see if that clears the problem, if so that wire must be shorted somewhere between there and the condenser.
Geo
 
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Old 06-24-15, 02:42 PM
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Ok I removed Y well the same two wires going to the contractor but inside this time. The fuse did not blow. I can't seem to find the short with them so I will try and pull some new wire and replace them.
Thank you very much Houston and Geo.
 
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Old 06-24-15, 10:10 PM
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You have proven it isn't the contactor and you have proven that it is somewhere between the contactor and the furnace.

Have you proven that it isn't between the contactor and the low voltage connections to the outdoor unit? You could be pulling wire only to find the problem still present if you haven't tried removing the 2 wire connectors to the outdoor unit.

 
 

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