Hey guys, I am at my wits end, and I seriously need some help.

Sometime in September of last year, all at once, my A/C stopped getting cold. I took it home and began to diagnose the problem. Compressor wasn't coming on. I checked the voltage at the clutch coil connection, and I was getting battery voltage when the A/C was turned on. Since the weather was getting cooler, I decided to wait until Spring to repair it. Ok, April is here, and I just replaced the clutch coil. Well, I assumed the A/C would start working again. Again, nothing. Except now, there was no battery voltage at the coil connection with the A/C on. I ran a hotwire from the battery to the coil, and the clutch kicked in. A/C started to get cold. Hooked up a gauge set -- low side 30 psi, high side 150 psi. Hmmm. Looks low, so I added some 134a. I added 3 cans, and the pressure still won't rise! Hooked the coil connection back together, unplugged the limit switch on accumulator. When I short the connection, the compressor kicks in. It seems that if the pressure would rise, the compressor would cycle on its own, but I can't seem to get the pressure up. Am I overlooking something? Please help!

 

Your stated pressure would be good if you had an approx. 70 degree ambient. It sounds to me like you have a failed pressure cycling switch. if you had 30 pounds of suction pressure when you jump the clutch, then it should stay engaged when you plug in the switch. you now are probrobly overcharged, so don't be suprised if you see the accumlator start to turn into a ball of snow. I would recover that refridgerant, vaccum down to 1000 microns, and start over with a new low pressure switch. good luck.

 

Hey bustech81,

Thanks for your reply. That was my next step, but I wanted to make sure before I went through all of the trouble. Thanks for your confirmation!

 

your welcome. happy to help. please update with your results.