I found this to be quite the issue on my '90 240 wagon, but here goes:

It's been about 1 year since i've had my volvo up on the road. Since then, she's been great to me (except when her alternator failed on me 300 miles from home on I-80 in PA). All she asks of me is to change her oil and perform general maintenance issues. But one issue I have yet to figure out is my a/c. My dad and I tried to re-charge it to no evail. The compressor never engaged. This was about a year ago. Since then I never really considered doing anything about it until I had it brought to my mechanic for inspection and such. I was planning a trip to Chicago with her so I thought it would be best to get the a/c checked out. He told me that there was a green wire from behind the compressor that needed to be spliced, so he put them together and started the car. He said the compressor ran for a few seconds, but then stopped and consequently blew the connecting fuse. I told him it was no worry to get it fixed as I have never been one who hassels over a/c (I've gotten used to driving cars in my family with no a/c. The only car that has it is my moms and I always roll the windows down anyways). So I went home, opened the hood and got an idea. I re-routed that wire around into the fuse panel, but instead ran it to a 16A fuse rather then an 8A. I ran it to the fuse for the power windows, but I forget which number it was. I started the car, compressor came on for a few seconds, then blew the fuse. I wanted to run it to the 25A, but I didn't have any extra 25A fuses lying around so I scratched that idea knowing my problem lies elsehwere. I feel like a pain in the you-know-what having to ask for a solution to my problem, but with the summer bearing down... I just might need a/c. Any thoughts on what it could possibly be, or what I could possibly do? I have a pick n pull auto yard near my house, so if need be, I can always go down there and pick up a salvaged part.

Thanks for any help, it's GREATLY appreciated!