a/c has me stumped

[thanatos9]

I push the a/c switch and only hot air blows from the vents. The compressor doesn't engage. When I short the pressure switch connector the compressor kicks into action but still no cold air. With my pressure gauge on the low pressure side with the compressor running it shows a vacuum and with the compressor off it shows about 31 psi. A receipt from the previous owner shows the compressor as new but it notes that a new a/c cycle switch will be needed soon. Whats an "a/c cycle switch" and would that be the cause of my symptoms?

 

[thanatos9]

never mind. I got it. There was almost no refrigerant in the system. It cycles on and off just fine now that the right pressure is in the system and the air cools nicely. This was the first time i used a refill kit with a pressure gauge on it so i didn't know the low pressure side should have been much higher with the compressor off. Hopefully i didn't partly burn up my compressor having it run a minute or so with the refrigerant as low as it was. If i did.. oh well. I'm not going to put hundreds into a 92 especially when I'm used to 2-60 a/c anyway.

 

[ld50]

I did that before and was thinking I was pretty handy.
Then my 40 bucks in refill gas was all leaked out again within a week.
You should check for leaks while it has pressure with some soapy spray water or something. I could never find mine though, probably too far gone now.

I have considered using that sealant and pressuring it all up again but would hate for it not to work.

 

[Maniak]

Just for future reference. Static pressure of r-134 should be about the same as the ambient temperature. e.g. If it was 80F out, you should have had close to 80 psi on the low side when you checked...

Good job on fixing it though..

~Mark