Noisy air con

[Kev0607]

Hello chaps, I hope you're all keeping well & safe.

So I was out for a drive this weekend in my car (2007 S80 2.4D). The windows started to fog up slightly due to heavy rain. I didn't need to put the whole demister on, so just decided to use the auto climate. So, I set the temperature to my desired setting, pressed "auto" & the air con engaged. After doing so, all I could hear was this really weird whirring sound that seemed to get louder as I accelerated & also a rubbing bearing noise. As soon as I turned the air con off, the noise stopped.

I'm assuming this is compressor related. Do I need a whole new air con compressor, or can a defective part(s) be fixed individually? (like a bearing for example).

I haven't had the car re-gassed since ownership, but the air con does blow cold.

Any help/suggestions are appreciated. Approximate repair costs would also be helpful.

Thanks.

[Spike56]

Multiple threads in each section on this. Seems to be very common! I just live with it. It tends not to happen if I put the a/c on at good speed only from a stand still or slow speed.
Someone will explain the fixes, I'm sure. Pretty much everyone seems to know about it.

[beach]

Hi, Loads of info on this if you search. But if you turn the aircon off but leave fan on and its noisy, you have a noisy blower motor. If it only comes on with aircon switched on and varies with engine revs its the expansion valve in the dash/bulkhead.

[Kev0607]

Thanks for the replies. So, the noise is nothing too serious then? A noise that I need to live with so to speak...

[37 RUBY]

Originally Posted by Kev0607

all I could hear was this really weird whirring sound that seemed to get louder as I accelerated & also a rubbing bearing noise. As soon as I turned the air con off, the noise stopped.

Whilst not dismissing the above advice (my own car has that exact foible) have you actually had a gander under the bonnet, and with engine off grasped the air con pulleys and tensioners to check for play or used a long screwdriver as a listen stick on the aircon pump casing when it's running.?

You wouldn't want to ignore a failing bearing, which might seize and snap a belt, what with the propensity of your engine to spit its dummy when an errant belt gets behind the timing case.

[Bonefishblues]

Speed-related whine sir?

Do mind if I do (incl on the low-miles OEM replacement compressor I was urged to buy, rather than an aftermarket part).

Frustrating, but I'm not sticking a 3rd one in there!

[37 RUBY]

Originally Posted by Bonefishblues

Speed-related whine sir?!

I find either leaving Mrs 37 Ruby behind or fitting a blindfold and handing over a family size pack of Maltesers cures that speed related whine...

Originally Posted by Bonefishblues

Do mind if I do (incl on the low-miles OEM replacement compressor I was urged to buy, rather than an aftermarket part).

Frustrating, but I'm not sticking a 3rd one in there!

I take it you've got the odd whining noise behind the dash then not a rubbing noise as described Kev0607's post?

Who urged you to buy the used OEM ?
When you spun the old compressor was it noisy which encouraged you to change it?

[Bonefishblues]

It's the compressor. Diagnosed by a well-regarded Indy. Suggested on here when I was discussing aftermarket (new) replacements. Bought a low-miles OEM replacement in great nick from a well-regarded vendor, also local, and the replacement does it too!

Hey-ho, put it down to experience and all that.

[richardt1994]

Had the same issue on my V70. My local independent suggested that it might be worth re-gassing first before thinking about changing the compressor as it had not been gassed for about 3 or 4 years. The re-gassing seems to have solved the problem for me. I am certainly no expert, but perhaps the compressor has to work harder when the gas pressure is lower, hence the noise?

[Bonefishblues]

System has to be regassed when compressor is changed so no dice there I'm afraid