I just returned from a work trip to a hot southern climate, and my house is struggling to cool down! I had set my thermostats to 80°F while I was away to save on energy bills. Upon my return yesterday, I noticed the temperature wouldn't drop by even 2 degrees. I tried to wait for it to cool down outside before messing with the AC, switching off the downstairs unit for a couple of hours and focusing on the upstairs, which initially seemed to be doing better. After turning the downstairs AC back on around midnight, it started to cool, but incredibly slowly, managing only to drop a couple of degrees in an hour. The upstairs cooled down to 72°F, while the downstairs barely hit 76°F before bed. My house has a large, open floorplan, so you'd think the warmth from downstairs would rise to the upstairs, but it's the opposite! I've already replaced the filters, and they're set up properly. The HVAC team is coming to diagnose it on Monday, but I'm wary since their techs haven't been great, and I've heard they might push unnecessary repairs. Should I be concerned?
4 Answers
First up, check the temperature difference between the discharge and ambient or supply air (coming out of the vents). You're aiming for about a -15°F drop. Also, look at the airflow coming out of the vents; if it's weak, turn off the AC and check for clogs in the condensate. Low refrigerant can also freeze the evaporator coil—keep an eye on that!
Sounds like you might have a refrigerant leak. I've experienced this a few times; the AC runs but just not cooling effectively. Getting it filled usually costs around $500 to $700 depending on how much is lost. You should definitely get that checked out!
I saw a trick on Instagram where someone put a permanent sun umbrella over their AC unit, and it helped save energy and money! You might want to look into some shading for your unit to see if it works.
My parents' HVAC guy installed an exhaust fan in their attic near the unit, and it made a huge difference. Might be worth considering!
It could take a while—like 24 hours—to get the humidity out before it can effectively cool down. That's a lot of work to drop the temperature a few degrees! Keep an eye on the humidity in your house, as that could be slowing things down.
I get that! If I can't cool it down at night, I'm stuck with 80°F until the next day. I'm worried it's a refrigerant issue too.
How do I find a refrigerant leak?