Central air unit shuts off each day for several hours, regardless of temp and thermostat setting

by Nora
(Oklahoma)

Why is my central air conditioner unit shutting off each evening? It cuts off and will not restart until late at night, when the outside temp cools down - with no changes to the thermostat.

The electronics portion of the AC is located in our attic. We thought that it may be overheating, so installed a temperature activated attic fan. This did not help.

The central ac unit works great during the morning and mid afternoon while it is running. Just can't figure out what is making it short-out(?) and shut off each evening.

Comments for Central air unit shuts off each day for several hours, regardless of temp and thermostat setting

Average Rating starstarstarstarstar

Click here to add your own comments

Rating
starstarstarstarstar
AC shuts off same time each day and comes on later in the evening. NEW NEW
by: Meeh

Hi Joyce, We have similar issues and have spent $$ to have different HVAC certified people to take a look (unfortunately none of the do free consultation).

My hubby who is pretty handy himself, has maintained our HVAC thoroughly. He has also replaced the capacitor, thermostat and cleaned all pipes, air handler and what not.

Most of the HVAC people that came over didn't have to do a thing but they could not figure out what is wrong. There are no leaks, the level of refrigerant is good. We are at a lost ourselves.

I'm hoping we find someone who can answer.

Rating
starstarstarstarstar
AC shuts off same time each day and comes on later in the evening. NEW
by: Joyce

Daughter has a CPI installed thermostat about a year ago. This summer the AC shits off around 2pm each day and doesn't come back on till after 8 pm. She has over $1,000 in AC service visits. No one can find any problems with her unit.

CPI came out to look at their thermostat and can verify they can't get the AC to run by adjusting their thermostat. Could it be a problem with their thermostat? They won't admit it might, won't change out their thermostat, just shake their heads and say they don't know.

She bought 2 new thermostats and is going to have them installed. If the AC works after installing the new thermostats then it's safe to say the problem has been and is CPI defective thermostats?

Rating
starstarstarstarstar
AC cycles off/on during the day but works perfectly at night NEW
by: anonymous

My central AC works perfectly during the night, but short cycles 5 seconds on, half second off on hot days. Any thoughts as to what would be causing this?

Rating
starstarstarstarstar
air condition turn off every morning then come back on hours later NEW
by: Anonymous

can anyone help me my cental aircondition unit works fine in the day then every morning around 1am it turns off then come back on around 9am in the morning.

Rating
starstarstarstarstar
comments saved money NEW
by: Anonymous

you just saved my ac guy a trip and me some money, my pan was full discharge was stopped up, now is ok !!...thanks for
the input

Rating
starstarstarstarstar
Compressor Shuts Down
by: Dadan

The compressor has a low pressure switch or internal safety switch. It would shuts off to protect the compressor from damage.

Had you have maintenance done on your central heating and air conditioning unit? It best to have local hvac tech look at it.

Rating
starstarstarstarstar
Outside Unit shuts down and then turns back on
by: Anonymous

What if it is the outside unit that shuts down about the same time every night, thermostat continues to blow air. Then later in the evening the outside unit comes back on and blows cold air?

Rating
starstarstarstarstar
Comment to NG
by: Anonymous

You are absolutely right. The overflow pan was filling up too much and causing the shut off switch to trigger. AC repairman said it would be quite expensive for him to fix the drainage issue. We've tried clearing the drain pipe ourselves - with minimal to moderate success and have now resorted to keeping an eye on it and using the shop vac when needed.
Thanks for the input!

Rating
starstarstarstarstar
To protect your ceiling
by: Ng

Without enough information. But let me suggest that the drain from the evaporator coil pan located in your attic may be plugged up. This unit set up should have a water overflow detection to shut down the operation of the AC before water run down your ceiling. Try to find and clear the drain hose from this unit and you may solve the problem.

Rating
starstarstarstarstar
Central Ac Unit Shut Off
by: Dadan

When you said the central air conditioner shut off each evening. Is it the outdoor shut off or both indoor and outdoor unit shut off?

If the outdoor unit shut off. Does the outdoor fan run and not the compressor?

Click here to add your own comments

Return to Central Air Conditioning Unit FAQs .