View Full Version : Heat pump auto cycling. Won't kick back on after shutdown.

01-09-2013, 01:16 AM
Hey guys, so I seem to be experiencing problems with my Heat Pump AC in my apartment. This happened all of a sudden and I really can't seem to figure out what's going on with the unit so I figured I would ask around before calling someone out to inspect.

After arriving home from work I noticed my apartment was a bit warmer than usual. About 76. Now up to 84... I usually keep the thermostat around 71. The units blower was running circulating the air but the air coming out was not cool. I immediately assumed the unit might be cycling but the strange part is I never turn off the unit when I leave home so it should have always stayed at 71 or thereabout. Now I don't recall my unit ever cycling before attempting to cool, most of the time it would run no longer that 30 or so minutes to keep the apartment at its target temperature...

So with that being said, I went over to the thermostat turned the unit off and then back on. The compressor immediately kicked back on and cool air was blowing out of the vents. About 45 minutes later the compressor kicked off and my apartment was still at 75 degrees give or take. I waited about 15 or 20 minutes but the compressor never kicked back on until I turned the unit off and on again at the thermostat.

This led me to believe my thermostat was going out so I went to Lowes and picked up a new one. They happened to have an identical one so I tried it with no luck. Same issue. Which leads me to believe the problem lies in the heat pumps controller circuitry or perhaps the ***** pressure being a bit too high or low. What I find strange is when I manually kick on the AC the compressor runs just fine but turns off shortly there after. Immediately if I turn the unit off and back on the compressor kicks back on and will run for another 45 minutes. Now correct me if I am wrong but I believe if it was a pressure switch triggering the compressor to kick off then if I would turn the unit back off and on again the compressor wouldn't start back up unless the pressures were within ranges right?

Now just to clarify when I say I turn the unit off I just flip the off switch on the thermostat not actually disconnect the power to the unit or anything. My thermostat wiring is a 5 wire: G, B, O, YW, R. I have confirmed I wired in the new thermostat correctly since the new and the old ones are identical. Does anyone have any ideas as to what the problem may be or any suggestions for me to try?

I would greatly appreciate the help!


install monkey
01-09-2013, 02:13 PM
filters clean?
temp diff range too wide on controller?
type of system and model number will help