Just got back from a 7 day business trip and my house is a friggin’ oven. I usually set the thermostat to 68, and ‘cool’ when I’m gone. However when I got home it was 83 degrees. Reset the thermo to try to kick the air conditionar on, waited for a bit and it’s just not cooling off. So I checked the AC unit and it appears to be running, but the air that is coming out of the fan seems to be a bit cooler than ambiant outdoor temperature (if I remember correctly it was usually pretty warm when running).
The AC unit is original to the house, making it about 18 years old. I was wondering if there is anything I can check to do some initial troubleshooting and determine if I should replace the entire unit outright, or have someone take some time to fix it?
Sounds like a loss of refrigerant. Evidently the compressor and air exhanger fans are running, however, just to be sure, make sure no fuses or breakers have blown/tripped. An 18-year-old unit is well overdue for replacement, but you might as well have an HVAC tech take a look at it, since he’d do the new install anyway. If it’s a simple repair and recharge, and everything else looks mechanically sound, he may tell you it’s economical to keep the old one going, but more than likely there’s going to be considerable wear and he’ll probably tell you that you ought to replace it. Definitely get a tech to look at, since inspection is really the only way to determine if it’s economically repairable or not. Good luck!
Find the unit and check for ice buildup. You might have blockage.
Fairly common, but you should stop running the A/C til fixed.
A leak out of no where? Hmm…maybe not a leak…check for ice.
Running the unit ‘blindly’ can cause this, such as leaving it on when away, while some nights are very cool, say below 70.
Check the unit. If ice present, turn off and let it defrost. Try again, and if problem returns you’ll need a tech.
Is the fan on the outdoor part of the unit working. If it is not, you are not getting rid of the heat at the condensor. That’s what I would check first.
I agree with Q.E.D. You’ve either blown the compressor motor or you’ve sprung a leak. You are correct that you should have warm air blowing outside. There definitely is a chance that you tripped a breaker that runs the motor, and its worth checking both coils to see if they’re dirty. Even if its simple, 18 years is long past the life expectancy of your unit and replacing it could pay for itself in a few years, especially if you like to keep the temperature cool.
Well, you are going to need to call for service. Best case scenario, system just needs to be recharged with refrigerant. This is typical maintenance which should be done on an annual basis. Our house has 2 units and annual recharge/service runs me about $150. If you have leaks or other mechanical problems the costs rapidly escalate from there.
While this is a possibility, ice buildup on the cooling coils is normally accompanied by very warm or hot exhaust, IME, since the refrigerant would still be carrying heat from the cooling coils to to the air exhanger outside. The air from the inside vents, however, would be barely warmish, since ice insulates the cooling coils and prevents them from efficiently cooling the air. So, he’s got about half the typical sypmtoms of ice buildup.
The coils in our upstairs unit froze up last year. The tech said that this was due to the system being low on refrigerant. After he recharged the system, we did not have another problem with the coil freezing up.
The most common cause of AC (or refrigerator) malfunction is dirt. Check to make sure air flow is unobstructed by dirt, dust, bird nests, grass, etc. before calling an expensive repairman. If there are filters, wash or replace.