need A/C help - 90 legacy 134a - UPDATED 8/9/04 - low side warm

[Guest luffliffloaf]

UPDATED 8/9/04

 

New information. Just talked to my mechanic and we did a few things and we determined that the low side is NOT cold at all. Not sweaty. Not frosty. Just room temperature. What do you guys now think it could be? Thanks

 

Intersting about the 24PSI by the way.

 

_____________________

 

 

Hello. I posted awhile ago and here I am again with more information.

 

90 legacy being converted from r12 to r134a.

 

New condensor

New receiver / dryer

New expansion valve

New fittings

System vacuumed / oiled correctly / etc...

 

Cooling fans run

No leaks

Compressor runs correctly

200 PSI high side / 30 PSI low side

I believe he said the heater control valve was fine.

 

Blowing air that is not cold at all. Air is room temperature.

 

 

Thanks!

 

Loomis

[Legacy777]

they really didnt' need to replace the condensor

 

Did they flush the system at all when they converted it? What type of oil did they use?

 

Did it ever blow cold air?

[mbshop]

check the a/c hose coming out of the evaporater.

 

if its cold then you got a heater control problem.

 

 

 

george

 

 

 

 

 

Hello. I posted awhile ago and here I am again with more information.

 

90 legacy being converted from r12 to r134a.

 

New condensor

New receiver / dryer

New expansion valve

New fittings

System vacuumed / oiled correctly / etc...

 

Cooling fans run

No leaks

Compressor runs correctly

200 PSI high side / 30 PSI low side

 

Blowing air that is not cold at all. Air is room temperature.

 

Thoughts? Someone mentioned a flapper?

 

Vague background info: Car had been converted at some point professionally a year ago, but I think it didn't work right or worked and then stopped and then winter came and the car sat. So the conversion was basically done twice and still no luck.

 

Thanks!

 

Loomis

[MailManX]

Compressor runs correctly

200 PSI high side / 30 PSI low side

Blowing air that is not cold at all. Air is room temperature.

I had my 94 Legacy converted to 134a a couple years ago and it started blowing warm air shortly after I picked it up from the shop. Since you said your compressor is running correctly, my problem may have been different from yours. In my case, I got cold air for a short time (a few blocks), then it began blowing warm air. It turns out that my compressor didn't like anything over 24 PSI on the low side. It would start to turn, then it would kick out.

 

Since the shop had already closed by the time I turned around and went back, I played a hunch... With the engine running and the AC on, I used a small screwdriver to bleed a bit of pressure off the line. With just a couple short burst of pressure relief, the compressor kicked in again and I got cold air. It lasted that way for several miles, then cut out again. I pulled over and let out another couple short bursts and got the compressor working again. That time it held permanently. I later bought a guage and measured the low side pressure at 24 PSI.

 

As a final test, I purchased a can of 134a and put about half of it in which raised the PSI to about 28. My compressor quit running. I then bled in short burst until the compressor would run continuously, then measured again. Sure enough, it was 24 PSI. That's what it likes, so that's what it gets, and nothing more!

 

I wish you luck in finding your AC problem right away!

 

Michael