A/C pressure switch question (already searched, no luck)
AintGotNoSol
Wagonist
I'm having this really weird problem with my air conditioning.
First some info: When I bought the car a few months ago, A/C did not work (the compressor would not engage). The previous owner said it needed to be recharged, but the system had not been opened. That guy was full of shit on many other issues, so who knows...
Anyway, I started to fill it with a 10 oz. can of R134 (it already had the updated adapters on the hoses) with UV dye to detect leaks. The compressor started to come on almost immediately. Just a few minutes into it, I found a leak, where one of the hoses connect to the condenser. It seemed to be a loose fitting, so I tightened down the hose, and the leak appeared to stop. I have no idea how much refrigerant leaked out, or how much was left in the system.
The compressor would still come on, but the air was not very cold at all. I bought a big 19 oz. can of super arctic chill 134a the next day and started to add it.
About halfway through, the compressor shut off, and then every 3 seconds or so, it would engage, and immediately shut off. I added the remaining contents of the 19oz can, and the problem still persists. The can had a pressure gauge on it, and it still says its below normal range.
I have been trying to work my way through the service manual to check all the relays and connectors and such.
When I unplug the pressure switch, and jump the terminals on the plug, the compressor stays on, but the air still doesn't get very cold.
I'm wondering if I need more refrigerant in the system. BUT if the low refrigerant is causing the intermittent shutoff, why did it not do it from the beginning, when it had no pressure at all in it?
I'm going to try to add more refrigerant, but if anyone has any advice in the meantime, I would appreciate it.
Thanks!
First some info: When I bought the car a few months ago, A/C did not work (the compressor would not engage). The previous owner said it needed to be recharged, but the system had not been opened. That guy was full of shit on many other issues, so who knows...
Anyway, I started to fill it with a 10 oz. can of R134 (it already had the updated adapters on the hoses) with UV dye to detect leaks. The compressor started to come on almost immediately. Just a few minutes into it, I found a leak, where one of the hoses connect to the condenser. It seemed to be a loose fitting, so I tightened down the hose, and the leak appeared to stop. I have no idea how much refrigerant leaked out, or how much was left in the system.
The compressor would still come on, but the air was not very cold at all. I bought a big 19 oz. can of super arctic chill 134a the next day and started to add it.
About halfway through, the compressor shut off, and then every 3 seconds or so, it would engage, and immediately shut off. I added the remaining contents of the 19oz can, and the problem still persists. The can had a pressure gauge on it, and it still says its below normal range.
I have been trying to work my way through the service manual to check all the relays and connectors and such.
When I unplug the pressure switch, and jump the terminals on the plug, the compressor stays on, but the air still doesn't get very cold.
I'm wondering if I need more refrigerant in the system. BUT if the low refrigerant is causing the intermittent shutoff, why did it not do it from the beginning, when it had no pressure at all in it?
I'm going to try to add more refrigerant, but if anyone has any advice in the meantime, I would appreciate it.
Thanks!
Comments
You're right, most cars were R12 until '93ish. The problem is that 12 is now prohibitively expensive IF you can even find any. I haven't even heard of any R12 for sale lately.
So it's pretty much 134a or bake. Even 134 has gone way up (like everything else except my pay :x ) a couple years ago I paid $69 for a 30# tank. Now it's $259.
You need a license to legally purchase R12.
The high pressure line would get cold enough to freeze up, but low pressure side wasn't cold at all, and the air from the vents wasn't cold either.