Whining AC

[Kev0607]

It could be the a/c compressor clutch that’s making a racket (I mentioned that in my post earlier in this thread).

I’ve read messages on other forums where people have changed the whole compressor with a view to getting rid of the annoying whine noise and it didn’t make a bit of difference.

The way I see it is you’ve had the new muffled a/c pipe fitted. So the only things that can make it noise is the compressor itself, low refrigerant or the compressor clutch.

Get it properly checked out. An a/c compressor isn’t cheap. It could be something small.

[Auldgit]

Originally Posted by GrahamBrown1

My S80 has suffered noisy AC for a while. It has always whined a little and at certain outside temperatures usually between 10 and 15 degrees it used to make a honking noise on then off on then off constantly. The whining went up and down with the engine revs. Really is quite intrusive inside the car. No noise from the engine bay however.

Thanks to info on here I had my local Volvo specialist change a pipe from
The compressor that Volvo updated with silencer baffles. It’s sorted the honking noise but the whining is still the same if not worse at times.

Noisy AC is a common issue on these cars, anyone sorted it once and for all? Thinking now is the compressor could be bad as well but it’s only done 45,000 miles. Our 2012 XC70 has a silent AC system and has never been touched to my knowledge.

Thanks

What is the part number of the replacement pipe??

[GrahamBrown1]

The whine noise is internal to the car in my case although the engine Revs vary the noise and it is much quieter at cruising speed. I’ve listened to the engine and there is no noise from the compressor externally other than the clutch clicking in.

My other thinking is the TXV valve or thermo expansion valve that sits on the end of the evaporator inside the car right behind the dash. Doesn’t look an easy job to change. I’m fairly certain the whine is due to noise in the system pipe work which a blocked or restricted valve could create.


One thing I have noticed is since the pipe was fitted the Fan clicks in as soon as the AC is turned on. It runs for some time. It never did this before. Anyone shed any light on why that would be the case?

The part number of the pipe I had fitted is 31407976. If you have means of degassing the system and re gassing yourself it isn’t a difficult pipe to replace and could be done at home.

It took some time for the pipe to come in as it was on back order with Volvo

[Andmurph]

Thanks guys!
I’ll have a look at the clutch as the AC is turned on and off. It’s an intermittent fault rather than regular for me but if the clutch or compressor do need replacing I’ll be sure to update that pipe as well.
It’s going in for trailing arm bushes next week so I’ll ask them to take a look as well.

[Auldgit]

Originally Posted by GrahamBrown1

The whine noise is internal to the car in my case although the engine Revs vary the noise and it is much quieter at cruising speed. I’ve listened to the engine and there is no noise from the compressor externally other than the clutch clicking in.

My other thinking is the TXV valve or thermo expansion valve that sits on the end of the evaporator inside the car right behind the dash. Doesn’t look an easy job to change. I’m fairly certain the whine is due to noise in the system pipe work which a blocked or restricted valve could create.


One thing I have noticed is since the pipe was fitted the Fan clicks in as soon as the AC is turned on. It runs for some time. It never did this before. Anyone shed any light on why that would be the case?

The part number of the pipe I had fitted is 31407976. If you have means of degassing the system and re gassing yourself it isn’t a difficult pipe to replace and could be done at home.

It took some time for the pipe to come in as it was on back order with Volvo

Well that's the same one that I used. Very strange...

[GrahamBrown1]

Bit of an update to this issue,

So today I had use of an air con machine. The constant whine was getting worse. I recovered 600 grams of gas out of the system. There are some charts including the machines data base that states the car should have 650 grams but the sticker in the engine bay and the Volvo website state 720. I also recovered from what I could see very little oil from the system.

So I have Re gassed the car at the 720 grams and added 100 grams of oil as per the Volvo website. Volvo state 110ml but went with a 100 as you never get it all out rightly or wrongly.

The result is a silent car. For now anyhow. Tho I performed vacuume tests and vacced the system for 45 mins and couldn’t see any obvious issues. Time will tell.

Another thing I also noticed was before the Rad fan would run straight away when AC was switched on. At this time of year that shouldn’t be needed. That has now stopped as well.

All of this for the cost of a few beers for loan of a machine. I hope it stays whine free. The compressor and other components are hopefully still good.

[bananarama]

Originally Posted by GrahamBrown1

The result is a silent car.

Excellent! Mine was also noisy, and then also quiet when it had its coolant/lubricant replaced.