AC making loud noise again after repair
The air conditioning unit is repeating a loud noise even after a recent repair, requiring the entire system to be switched off to stop it. This ongoing malfunction prevents the unit from operating normally and leaves the home without reliable cooling.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Fully turn off the AC switch to stop the noise
- 2Turning off the thermostat
- 3Spraying debris off the unit
- 4Digging old oscillating fans out of the garage
- 5Ensure the unit has a slight fall to the outside
- 6Make sure any drain ports are clear
- 7Accepting the technician's assurance that the noise is normal
- 8Listening for refrigerant sloshing to check if the unit is running
- 9Waiting for the installer to return and inspect the system
- 10Turn off the air conditioner unit
- 11Go find a replacement at Home Depot
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“I recently noticed that there is a constant noise coming from Evaporator and/or refrigerant line.”source ↗
“It seems to constantly cycle, and change its tone, almost how a shaving cream can would sound different as it gets close to empty.”source ↗
“My Rheem certified tech says it's normal, but I can hear this a floor away, and this noise was not there when the system was new.”source ↗
“It has been a month since the repair in the same noise as happening again, but louder.”source ↗
“The only way to get the noise to stop is to fully turn off the AC switch.”source ↗
“Just got home and noticed the AC unit making an insane amount of noise.”source ↗
“Air was blowing in the house but the unit wasn’t kicking on at all — usually it kicks on right away so I’m assuming that’s a bad sign.”source ↗
“It’s not full of water, I drained it. Is it hitting something?”source ↗
“It’s one of those U-shaped ones. The weird thing is, it is tilted back enough, but the outside is bone dry. Meanwhile the front of it is just POURING water.”source ↗
“Very odd. Can hear it throughout the condo. Cannot be normal for a system that is supposed to be very quiet.”source ↗
Where this came up
People with this problem also raised
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- 7Why is my AC making a weird noise when it turns on?