S90, 1998 A/C isn't working properly

[RNCharlie]

Hello All,
I'm new to the site with a question. My wife's 1998 volvo S90 A/C isn't blowing cold air. Here's the story... She has had a slow leak , I assume, and last summer required a recharge which I did without a problem. She was using the A/C at the beginning of the summer with no problems. The weather has been unusually hot and this afternoon its was blowing cold and then just stopped. She says it was blowing hot, got cool and back to warm/hot and doesn't seem to blow cool now. The Compressor is running, condensation is dripping from the bottom of the car, the thin line going into the firewall, High side I think, is ice cold but there is no cold air blowing. The Low side reads about 27lbs while the compressor is on and in the 100's when I turn the A/C button off. So...where should I go from here? I appreciate any feedback. Thanks!

[Ethan Rode]

I'm raising this one from the dead...

I would recommend actually finding the leak and fixing it before doing anything else. There aren't many connections, and your accumulator is probably ready for a change by now.

Evacuate the system to a hard vaccum, add UV dye and enough R134a to make the compressor kick on.
Hopefully you'll find the leak pretty quick.

After you've fixed the leak, like the conscientious Volvo owner you are, you can go about solving your issue. It sounds like your compressor is working. My guess is that the orifice tube is blocked. You'll find it inside the connection on the hardline that is on the passenger side frame rail. If you pull it out and there is debris in the screen, then you've found the problem. Replace it with an adjustable oriface tube from your local parts store.

You'll then need to pull a vacuum again, and refill the system based on WEIGHT, NOT PRESSURE (very important!), because there is no high side service port, and something WILL break if you overfill the system. I use a fish scale to weigh out partial cans, a food scale would work too. Use plain ol' R134a with out the fancy additives.

Another thought-
A clogged orifice tube is an indicator of compressor wear. You should expect to do a condenser, compressor and accumulator in the coming years, but enjoy the cool air in the mean time.

[lindy8_man]

I don't think fixing the slow leak will fix this. Charlie says the ac line is frosty, and condensation is dripping. Is the compressor cycling on and off rapidly ( 3 - 5 sec)? This is indicative of a system that has lost its refridgerant.

I would eliminate the well documented vacuum motor leaks. or a climate control door that is broken. Is there cold air blowing on the floor?

[maframm]

Leaking air through vacuum lines, easy fix, you just have to find the leak, they are located near the fire wall, about 2 or 3 inches long 45 degree angle. With time they become bristle and air escapes.