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Heating, Air Conditioning, Fridge, HVAC/Outside compressor unit pops breaker occasionally


QUESTION: We have a Lennox unit outside for our ac system I believe 5 tons.The system as a whole works fine and then out of no where it would pop a breaker on the outside compressor line leaving the air handler inside running.The tip off is usually the increase in temp inside the house even though the handler is pushing air around.  I could reset the breaker and it would work fine after that but this seems to have been occurring more often last season and wanted to be proactive before this season starts.Lennox M/N 12 ACB60-3P SN 5897E 14459. I have a multimeter and I know how to use it,could this be a capacitor issue? Thanks in advance

ANSWER: Ralph,
the compressor breaker/condensing unit should be for the compressor/condensing unit only, the inside air handler is on another breaker.
The rating plate on the outside condensing unit should say what size the breaker should be?
sounds like the compressor or condensing fan is starting to run under some stress?

---------- FOLLOW-UP ----------

QUESTION: Yes that's how it's set up its not a breaker issue. What I want to know is how to troubleshoot the unit. I realize its under stress and therefore popping the breaker. What would be the next move to relieve this stress? A faulty component ? What to test,etc?

Get an amp probe and check the starting amps and running amps on both the condenser fan  motor and the compressor, check the rating plat and motor tags to compare what it should be, when you discover which one is causing the proublem, it could be any one of a number of proublems including a bad breaker.  

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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