Q&A help diagnose why the outdoor compressor/condenser unit shuts off or won't keep running when it should .
Photo at page top: a 3 decades old outdoor compressor/condenser unit that was still working properly - evidence that some HVAC equipment can work well for decades.
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These questions and answers about troubleshooting and fixing air conditioner or heat pump compressor/condenser units were posted originally
at COMPRESSOR / CONDENSER DIAGNOSTICS - be sure to check out the diagnostic suggestions on that page.
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My AC unit during the hot and humid months here in FL, will not run without some help from me. Lets say it is 80 degrees and you set the thermostat at 75, it will run until temp drops about 3 degrees, then shuts off.
You then need to shut the unit off via the thermostat, for approximately 20-30 mins turn it back on in order for the air to start blowing again. I tried changing out the thermostat but this has not helped. What could be the problem? - (June 8, 2012) Renee
Reply by (mod) -
Renee, often when shutting off the A/C returns the delivery of cool air we trace that problem to frost formation on the cooling coil.
Click on FROST BUILD-UP on AIR CONDITIONER COILS check for, diagnose, & repair that problem. But first, make sure that your air filter is not debris clogged.
A/C turns off during the hottest part of the day for two+ hours. On 2020-06-28 by Christine -
by (mod) -
Christine
Some AC systems include safety controls that will shut the system off to prevent more-costly damage from, for example, overheated components or excessive refrigerant pressure.
So I suspect your system, when it's working hardest, has a component that's overheating or otherwise causing a condition that shuts the system down.
An experienced A/C service tech can track down the failing part.
heat pump compressor turns off randomly but fan keeps running On 2020-05-22 by fred -
by (mod) -
If not one of the causes above on this page, perhaps a bad relay, control, or even a loose or bad electrical connection.
What will make your fan on a heat pump cut on and off On 2018-11-14 by Terry -
by (mod) - check the defrost cycle first
Possibly a problem with the defrost cycle.
My A/C compressor broke about two weeks ago, we got a new one but when the fan starts the compressor works for a while and then it shuts down, and its turning on and off and I dont know whats wrong - Help.
Reply:
Help: if your new A/C won't keep running after it has just been installed, surely you should call the installer and expect it to be repaired under warranty - it's just been two weeks.
Even if all of the new equipment is in good condition, an example of a problem that could occur during compressor replacement is that contamination, moisture, dirt in the refrigeration system (which is made worse if a compressor burns up) can interfere with proper system operation.See our diagnostic procedure
at SHORT CYCLING AC COMPRESSOR
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Compressor / Condenser Unit Won't Stop Running
Moved to COMPRESSOR / CONDENSER UNIT WON'T STOP RUNNING FAQs
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HVAC Compressor/Condenser Fan Won't Start
Moved to COMPRESSOR / CONDENSER UNIT FAN WON'T START, WON'T RUN FAQs
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A/C or Heat Pump Outdoor Compressor/Condenser Unit Won't Start / Won't Run FAQs
Moved to COMPRESSOR / CONDENSER UNIT WON'T START or WON'T RUN FAQs
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