I'm going to try the bread tag repair. I haven't measured the clutch gap yet but I have the symptoms. The A/C cools well until it heats up. Then it quits. When I drive it 15 miles to and from work, it's fine. When my wife runs errands around town, she says it's not cool enough. Some of this may be from driving a black car for short trips in 98 degrees. Anyway, I'm going to measure the gap Saturday and add bread tags if needed.

I've considered painting the roof white or carrying a heat shield on my luggage rack like the safari vehicles, but that would be weird.

Any other advice?
TIA!

David, after playing around with my AC, I found that you might be a little low on R143a. Drive the car a little with the AC doing its thing and then check the 2 pipes going to the firewall. The one on the left should always be very cold. The one on the right should also get cold when the blower speed is reduced slightly.

If the pipe doesn't get cold, add 1/2 can (6oz) to the system and see if the vent temperatures get a lot colder. At idle, the AC system doesn't work as well, try 2000 rpm for best cooling. There is an 'optimal' amount of regrigerant for hot weather Vs cold weather because of the gas expanding with heat. If you put in much to much, the system could blow the pressure relief valve - I did that once and no harm done, it just scared the heck out of me with a big BANG and fluid on the ground under the engine.

Klaus
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Always willing to listen, just not able to take direction.

Thanks, Klaus.

I remember your post about adding too much R-134 and then blowing it out as you drove along.

I put the gauges on last weekend and it held an even 45psi so I didn't add any. The temperature was running in the high 90s last week, maybe the A/C just couldn't keep up. Is it safe to run it up to 50ps1?

I had a leak last year and I worried it was the evaporator. An indy added some new kind of stopleak that's supposed to be okay. I know that stuff is iffy, but it's worked so far.

Thanks again,

David

One of the suggestions given by an indie (non-Volvo) shop was to check the clutch clearance. Large PITA to do, since it means pulling the compressor.

Been fussing with the a/c (ACC system) on my 1997 965 for several years. Same symptoms as yours: Cools to icy cold, does OK for a while, then kicks out and needs 5 to 20 minutes to return. Meantime the cabin and occupants are heated to too-F-hot in Houston's high humidity 95F summer climate. Bought the wife a S/90 with a working ACC system.

Last month I had my indie Volvo shop do a full ACC check, and a drain and refill of the R-134a. No leaks found, and now I know the refrigerant is at the proper charge amount. Same symptoms. So, thinks I, maybe I have set the temp too cold enough and it is icing up.

With all three knobs on horizontal (Auto fan speed, air directed everywhere, and 72F temp) and the recirc button OFF, the system works much much better.

Not long after start-up in a hot car, the system gets the cabin comfortable and the recirc indicator, which turns on automatically, turns off and the fan speed drops from max to about #3.

Any chance you are experiencing such an icing problem?

Give it a try - less expensive than any other suggestions I have gotten som far.

Good Luck

Bob

:>)

PS That system of open doors and letting the super-heated cabin air out before getting in to depart is an excellent idea. I am always amazed that such a small breeze will blow a such large charge of hot air out.

I had about 90psi, a bit much! My problem was the temp was about 65F when I left the house and drove to Ohio where it was 85F. Sitting in the sun, packing up my daughter's dorm stuff cause the gas to expand to probably well over 150psi.

You will be good at 60psi, without any real problems. When the car has been run for a while, the engine stopped and very hot will raise the pressure to well over 100psi. As soon as the engine is restarted with the AC on, the pressure will drop back to normal levels.

Close the fresh air vent in the center dash and check the temperature. It should be at least 20-25 degrees coolder than the outside air. I have never seen 45F on my car, best I have ever gotten was 55F on a cool day (under 80F).

If it leaked last year, add 6 oz and see if it gets better. I don't trust leak stop stuff.

I am going to bring my car in for a new schrader valve and a vacuum test. If it holds a vacuum then the evaporator should be OK? Hopefully the pressure will last longer than 3-4 days.


Klaus
--
Always willing to listen, just not able to take direction.

This is not an American AC system which is on full time and one needs heat to regulate the temp. I suspect your clutch gap to be OK.

What is probably happening is the compressor is running full time to reach the desired cabin temp. This is what I do - after parking in the sun, my V70 is black, I open all 4 doors, the hatch and pop up the sun roof, rool down all 4 windows. Then I turn the blower off before starting the car, set the temps to 78F and start the car. A second trip around the car to close all of the doors and hatch, leave the SR open. After about a mile, turn the blower to automatic and recirc off, if the ECC turns on the recirc. Make sure the center dash vent is not letting in fresh air.

Then close the windows. At least the cabin won't be at 150F.

If the compressor shuts off because of over heating, turn the blower off, wait 5 minutes with the window open, and turn the blower back on. At no time should you turn the temps below 78F to get colder air, it just won't work.

Some have disabled the fail safe switch on the compressor so the compressor keeps running. I don't like that idea, even if it works. New compressors are expensive to replace.

Klaus
--
Always willing to listen, just not able to take direction.