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HVAC Forums => HVAC Help => Topic started by: rsites on July 28, 2008, 05:47:30 AM

Title: RUUD outside unit shuts down after 15 minutes of cooling
Post by: rsites on July 28, 2008, 05:47:30 AM
My outside unit comes on fine, cools great for about 15 minutes and shuts down. Won't restart till after some period of time. During this shutdown, the inside air handler keeps running just fine, but of course is blowing hot air. Any ideas on what is causing the outside to "trip" like this? Power is not lost to the unit.  As a non-HVAC professional, I've worked on this unit before, fan motor, defrost board, etc...  It's an Acheiver 13 unit.  Not afraid to get dirty, just don't know what to check in this instance?
Title: Re: RUUD outside unit shuts down after 15 minutes of cooling
Post by: Admin on July 28, 2008, 07:10:24 AM
Does everything stop running outside?  I would check to see if the contactor stays pulled in.  You should have 24V across the contactor coil.  There may also be pressure switches, low and high, in series with the 24V contactor.  Your outside coil might be plugged, and the pressure might be running too high, causing the unit to trip off on the high pressure switch.

Title: Re: RUUD outside unit shuts down after 15 minutes of cooling
Post by: rsites on July 28, 2008, 11:18:34 AM
I believe that everything stops outside.  For sure the fan, but not sure if the compressor is still trying to work?  Seems pretty quiet and dead when I had the cover off though.  I'll check to make sure all is dead.  Can you tell me where to find the Contactor?
Title: Re: RUUD outside unit shuts down after 15 minutes of cooling
Post by: Admin on August 05, 2008, 03:41:48 PM
Follow the skinny wire that enters the outside unit.  That's the low voltage wire, it connects to the contactor coil.

Take a hose and spray the outdoor coil.  This might solve the problem, if in fact the high pressure switch is causing the contactor to open.