- Joined
- Aug 14, 2014
- Messages
- 4,446
- Reaction score
- 1,489
- Location
- Madison, WI
- My Car
- 1971 Mach 1 w/408C stroker
So here I am again having A/C issues. Over the winter I installed a Classic Auto Air system using the Sanden compressor I had. After the install I took it to a shop where they pulled vacuum for 30 minutes. It held vacuum, they charged it and I had very cold A/C for about 3 weeks. I last tested it last weekend and it was blowing cold. This weekend I took the car for a ride and had only warm air. When I checked under the hood I could see the compressor clutch was activated, the pressure line out of the compressor was hot, the line out of the condenser was at about ambient temperature, and the expansion valve at about ambient as well. This was weird and made me think that the expansion valve was clogged or something. Then today when I tried to diagnose with the manifold dials, the compressor was not activating. Now the pressure switch was cutting the compressor off because the pressure was low. I jumped the switch for a couple seconds and the compressor clutch activated. I connected the manifold gauges and confirmed that the pressure was low. These are the dial readings with the compressor activated and not:
Compressor off: low side @ 20+ psi; hi side @ 25ish psi
Compressor on: low side @ -10 psi; hi side @ 50-60 psi
So it appears that I lost refrigerant pressure, which may indicate a leak. What it is strange, why was the compressor activating the day before but blowing warm air and then the next day I had a low pressure issue? Also, if I have a refrigerant leak, should I be able to see an oily area to indicate where the leak is? All looked clean along the A/C system.
Thank you.
Compressor off: low side @ 20+ psi; hi side @ 25ish psi
Compressor on: low side @ -10 psi; hi side @ 50-60 psi
So it appears that I lost refrigerant pressure, which may indicate a leak. What it is strange, why was the compressor activating the day before but blowing warm air and then the next day I had a low pressure issue? Also, if I have a refrigerant leak, should I be able to see an oily area to indicate where the leak is? All looked clean along the A/C system.
Thank you.