Air Conditioner gets warm after an hour
 

This is my wife's car and she explains to me that after one hour and fifteen minutes (yes, she timed it) the A/C gets warm. It starts out nice but then warm. She found this out last week while driving from Phoenix to LA.
The car is a 2015.5 V60 which of curse is out of warranty now.
Any thoughts before I take it in?
Thank you in advance.
Sal

It could just need to be charged. There is an A/C hose towards the bottom of the front of the engine. Check that hose for leaks.

a few things come to mind - the AC charge could be too high or too low or the AC clutch could be overheating and disengaging or possibly the evaporator is icing up so air can't flow through. I had that problem on my VW CC and the dealer said my AC was overcharged slightly! Made sense to me as when I would park after a drive on a really humid day, I'd get a puddle of water under the car.

Either way, you will need a professional diagnosis. As a quick test, see what happens when you turn off the AC for say 5 minutes during the drive? does it start blowing cold again upon restart? If you turn off the car then restart, again does it start blowing cold again?

Any chance the cabin air filter is due to be changed?

My wife said that she would turn it off for about 30 minutes and then back on again and it would be cold again. Then the cycle repeats itself.

I have the car serviced regularly. I do not think they would miss the chance to change the cabin filer.

We have an S80 to compare and the A/C in that car is great.

Other cars I've owned that exhibit the same example was most always the air gap in the AC clutch.

On our Honda it was a 15 minute operation to remove a shim and that compressor will be good to go for a while.

On the Volvo's it is normally adding a shim (search bread clip fix) A/C COMPRESSOR SHIM FIX: BREAD CLIP. And it isn't a 15 minute fix. It is hard to see if the clutch is engaged but when this happens try to see if the clutch is engaged.

What is possibly happening is that your AC clutch is showing fatigue. Did you say how many miles are on the 2015?

Now if there are not a lot of miles on the car, it may be something else. If you had any refrigerant added, it may have too much in the system and the high pressure switch is shutting things down after driving for a while. If it were me I'd be hooking up my manifold gauges first and then go from there.

yep, I mentioned the clutch overheating in my post but forgot to note that the overheating is typically caused by the clutch gap being too large. the gap should be about .3mm and when it gets over .5 or .6, it starts to slip. when it warms up the solenoid loses force and it slips some more until it overheats and fails. The good news is on some models there's enough access to the AC clutch to reshim without opening the system but many shops would rather install a replacement compressor to be sure of the fix.

Had similar symptoms in our S40.

My fix was to remove the clutch (one centre bolt) and there was 2 shims at the end of the clutch shaft. I removed the thinner of the 2 and put everything back together. 9 months later, she is still enjoying cold A/C

If you're game enough, when its hot and the A/C is turned on but not running, look at the clutch pulley and see if it's engaged. If not, find something to give the clutch a love tap with and if it engages, you have the same problem that I had, Excess gap between the 2 surfaces.

Good luck and keep us posted