Repair Shop fixed my AC... now I have a noise

[wafogg]

I finally took my truck, a 2012 Ram 1500 to the repair shop the other week to get the evap core replaced after a year and a half of dealing with no AC. It was a fairly expensive job and i didn't want to fork over the money till now. They replaced and gave it back to me saying everything was working, and it has been. It blows perfectly cold but now it has a noise that happens when the compressor cycles. It sounds like wind wooshing though a window. It wasn't doing that prior the AC not working. The shop thinks its happening because compressor sat for a year and a half without running and says a new one may fix it. Anybody have any ideas for me?

 

[TJP440]

Does the noise occur when the compressor is ON of OFF ?

And does he guarantee it to resolve the issue???

 

[18CrewDually]

Are you sure you're not hearing the refrigerant going through the orifice tube? Or is it a sound in the hvac box? I'd try to isolate the noise and confirm.

 

[wafogg]

It happens when the compressor is on.

 

[Jeepwalker]

Is the sound air? Where is it coming from? The heater box? Is it the compressor making that sound? They would have had the dash apart so there could be a lot of possibilities. Could it be the compressor clutch is 'slipping'?? Making a sliding sound? Try to isolate where the sound is eminating from (exactly)...

The compressor and AC system is sealed. If your system had even a small amt of pressure on it, not much can happen inside there. And plus there's a lot of oil in a compressor which you can't hardly get out even if you tip it on end. You almost need to take the back off to get all the oil out. I just started my land rover up today after sitting at least 2yrs ...maybe 3 w/o running. Took right off. The AC works fine like it always has ...and blows cold! That's not ideal to let the AC sit, but.

It could be, if the sound is from your actual compressor ....maybe some of the friction material has fallen (rusted) off the AC clutch, or the clutch face which is normally nicely machined flat, has become rusty and is slipping. Slipping on the rust (??). That would (could) make a metal-on-metal ..some type of whirring sound. There could be rust behind the clutch too ..is it a bad bearing?? A guy could just remove the clutch and clean any rust off the clutch face with sandpaper. Or replace the clutch bearing assembly (not the whole compressor). You can do that on-car w/o touching the AC charge. That's almost a DIY (look up a video). Shouldn't be very expensive to buy a new clutch off Amazon/Ebay or wherever. I've replaced several of them over the yrs. If it's internal to the system maybe they introduced some crud into the system in the process of replacing the receiver/dryer. I would think they'd be careful...but you never know. And maybe the compressor *is* crapping out. Maybe it's air blowing past an HVAC damper door?? Hard to say. You're going to have to narrow it down for us (or have a pro narrow down the issue).

Try doing some google searches or watch some AC Noise ..videos. W/o being there it's impossible for me or anyone to say.

Maybe drive by another AC shop ...or two in your area, and get some 'free' thoughts/ideas.