Here’s a challenge, well it is for me and my A/C man,
A few months ago I noticed a whirling sound (appears to be from engine bay) very faint to start with
When the a/c is ON, switching a/c OFF the sound immediately goes,
Switching a/c back on it returns again,
This only happened once engine has warmed up and above 1600 RPM rising and falling
With the engine revolutions,
it’s inaudible at idle and with engine rev’s increased whilst Stationary!!
Now this has progressed and the sound has increased in volume (even passengers can hear it now)
It only happens in connection with a/c being switched on,
I had the condenser replace earlier this summer with a complete change of gas/oil
It has since been rechecked, it’s running at correct pressure and achieving -8 at the dash vent (ambient was 30deg)
The obvious culprit would be the compressor, but my a/c man with 19 years trading has not
Had this situation before.
Also NO fault codes are showing.
Dave DAVE.

I have a similar noise, I'm 99% sure it's the cabin blower fan.

Try running the HVAC in econ mode at different fan speeds. That might help rule out the compressor.

I'll probably replace my fan when I get time eventually but it hasn't gotten any worse so just annoying. Can mitigate the noise by playing the radio or turning the fan speed down manually.

I had similar
In my case it was the bearing in the ac clutch 2008 xs
Snorkel
raised axle/gearbox breathers
Mantec tank guard
Cb radio
Blanked EGR
Sump guard
Scratches
Snolkle

Thanks for the input guys,
Merlin, definitely not the cabin blower,
cqr, a bearing in the clutch! I'm seeing my a/c man on Monday so I'll mention it,
to be honest I didn't think it had a clutch as such,
I'll let you know the outcome, I feel a large bill will be coming,
although in his favour he doesn't
want to change it until he's 100% sure it is the compressor.
Dave DAVE.

cqr wrote:

I had similar
In my case it was the bearing in the ac clutch

Not saying this the same problem, but my AC pump seemed to get very noisy , but would quieten down after a couple of minutes driving. I tried a few things to isolate exactly where the noise was coming from and it definitely sounded like a dry clutch pulley bearing on the compressor.It would go away for a few days if WD40 or the like was used. It was suggested that the air con needed re-gassing as that could be the cause. Had it re-gassed 3 days before going on holiday and the noise did seem to quieten down. However, the noise came back with a vengeance on holiday until there was an almighty squeal and loss of power steering. Turns out the aux drive pulley was the culprit. It seized and destroyed itself and the auxiliary belt. Strange thing was, every attempt I made at quietening what I thought was the culprit, the ac compressor pulley bearings, seemed to work - although only briefly. The WD 40 and whatever else I used must have been getting into the aux pulley.

The sound is now noticeable around the 1000RPM so it's improving
motors being pick up on Monday,
so maybe we'll make a decision on whether changing the compressor,

my a/c man has been in the trade for 19 years and very rarely had a Freelander 2 in, generally just for condensers
and re-gas,
he's had only one other Freelander which had a compressor fail, but that was making a totally different noise!!
Dave DAVE.

Last edited by Dave47 on 4th Sep 2019 7:49 pm. Edited 1 time in total

If its any consolation, according to the workshop manual (TD4) it doesnt look like its a huge job to get the AC compressor off and on:
Recover refrigerant from system.
Remove undertray
Remove aux drive belt
Remove AC compressor
Nothing else needs to come off.

Install in reverse order and re-gas. Jules

Well, just to update this tread,
the compressor has now been replaced and all is quite now.
so it was the compressor the sound had got louder and noticeable at below 1000rpm,
bit of a big bill, but haven't had that much go wrong.
Dave DAVE.