My central air won't stop running!

[repair]

I'd suggest that THIS unit is low on coolant...

Our HVAC unit is 25 years old or so. On it's last legs.

Finding the money to replace it won't be fun...

While it's so hot, I turn it to 80. After it cools off at night, down to 78 to sleep. Yes, it does shut off...

78 + ceiling fan + pedestal fan blowing on me = win

We had it looked at and they say it's fine.....kids had the thermostat turned down to 60.....mr duck tape has put a stop to that practice!

 

[Benny]

Might be ****in hot outside.

LOL, it worries me that this was THIRD on the list of possible problems.

 

[jkaetz]

I occasionally spray my outside coils down with a sprinkler. It helps reduce head pressure and promotes cooling. Our a/c unit at work had this done as well and the building cooled amazingly quick.

I've always debated about something like this. Their system even takes it a step further and adds a shutoff for the mist.

 

[bman1962]

We have a winner! If it's like my home, the builders put in the bare minimum. Works fine most of the time but when the weather is over 90 it'll come on around noon and run until 10 or 11 at night. Only good thing is that it's so small it can't run the electric bill up that far.

This is exactly what it should do. A unit that is running constantly in this weather is wringing the moisture out of the air all day long. It is actually better to have a unit that is slightly undersized than over sized. Your comfort will be better with the smaller unit.

 

[BDBHoover]

May need the sequencer changed out in your air handler as it is probably not communicating with the outside unit properly

 

[GodFearinGunTotin]

I have my CENTRAL A/C set at 80*

My wife would divorce me if I tried to set our thermostat that high

 

[RobbyMaQ]

yeah I had a problem with mine a few days ago....

Ouch! Very Dirty Air Filter perhaps?

 

[churchmouse]

We run ours at 75 during the day and it will hold that temp unless there is a lot of activity and the wife decides to bake. The oven knocks the h%$# out of it if it is above 90 outside. We keep it 72 at night.
Mine is sized correctly. It is what I do for a living.
The A/c systems sold in this part of the country are designed to run at 100% up to 90 deg. if the filter is clean and the unit is maintained ie. clean coil and proper charge level. Above 90 deg. the eff. drops off. At 100 they are all struggling.
Use the hose and clean off the condenser coil. Keep a clean filter in the unit especially during the high heat. Keep un-needed lights off and do not fan the doors.

 

[LtScott14]

We use to put a sprinkler on Supermarket condensors when it hit 95 degrees. Roofs were only 110 or so, it helped. Even after cleaning, the heat from the black rubber roof would be a killer. Put a slight mist on my a/c, staying 76 deg today in my house.
102 is what the bank said, my Fluke digital thermometer said 99.6 in a shaded spot.
Running all day.( I have 30 yrs Com Refrig experience) 2 more days till temp breaks.

 

[U.S. Patriot]

The AC in my apartment is strugling to keep up. Can't wait to see my $150 electric bill. Have been wanting to reload, but it's to hot in the kitchen.

 

[IndySSD]

Yeah my AC has been running 18-20 hours a day, but that's mostly because my wife has a couple medical conditions that are severely inflamed by heat and we keep the house between 68-71 degrees and our MBR is between 64-66 degrees for when she gets hot flashes.

We have a small (1260 sq ft) ranch that's ~ 7 years old with a normal sized unit for that sq footage ( I don't know the exact capacity) and we generally got 16-18 degrees below outside temperatures due to some windows that need to be replaced and an attic that was horribly insulated.

In order to get down 30 degrees from outside temp (we were @ 71 when it was 101 yesterday) we added a window unit in the MBR that we run from ~1100-2100 every day during this heat.

The electric bill may skyrocket but my wife and son's physical comfort come first.
A trip to the ER for my wife will cost me 150-250$ out of pocket whereas the added electricity might cost me 45-75$ and I'll have a happy, healthy wife.

I highly recommend making sure you THOROUGHLY clean your coils (both the outside and the inside coils) if you're familiar with your system. If you're not familiar with HVAC (I'm no expert but I have to deal with this @ work and have done my own as well) the biggest thing to be careful of is not to use high pressure water on your coils, don't use any non HVAC cleaners, generally going slow and smoothly with a garden hose and your thumb, blowing the gunk out from between the fins is enough to improve the effectiveness of your unit if you haven't had it maintained by a service.

Also, with systems running nearly all the time like they do in this weather, it can take as little as 1-2 weeks for a system to build up more material in the condenser coil affecting the performance/efficiency of the system. We've had units where I work start alarming for high head pressure as quick as 5 days after a cleaning and when we went back to clean it you couldn't even tell it was cleaned recently.

Any "REAL" HVAC pros feel free to correct what I've said here, these are just the observations of someone who calls contractors and facilitates/explains the resolution of HVAC alarms, not an actual certified HVAC tech.

 

[williamsjr22]

My A/C used to run all day without turning off. I replaced the all the windows with a Low E 366 glass and added a lot of insulation in the attic. I have 3 bay windows that are over 100" wide within 20 feet of the thermostat. My house is a 2800 sq ft. ranch and my air has been running about 6 hours a day set on 70. It used to run over 20 hours on hot days.

 

[skydelta34]

Before you try anything else, check your filter. I have seen alot of situations like the op described fixed by changing a dirty filter.

 

[miguel]

I feel your pain. Well, I used to...

We replaced our 30+ year old HVAC system with a new 95% Carrier furnace and 3-ton AC in March and while writing the check nearly caused me to have a combination of heart attack, stroke and St. Vitus dance, it was the right thing to do.

Our old one used to freeze up like the photo above...now the only thing cold is Mrs. Miguel. We've had the thing on 73 or 74 for about three weeks now and are quite comfortable. The side benefit is the new refrigerant is Yeti, puppy and polar bear friendly.

Before you try anything else, check your filter. I have seen alot of situations like the op described fixed by changing a dirty filter.

And also hose the thing outside off. You'd be surprised how nasty they can get sucking air all day.