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2000 Chevy Z71 Pickup

My a/c will work for about 5 minutes and then stop blowing cold air like when a car a/c freezes over. I can turn of the a/c for about 3 or 4 minutes and then turn it back on and it will start working again usually for about 5 minutes. You can keep following the same sequence and get the same results all day.

I had a friend that does a/c work check the refrigerant and he said it was a little low. Still had the same problem, so the same guy completely evacuated the system and recharged it to specs. Still the same exact problem. Next we replaced two of the in line pressure switches. Still the same problem. I had heard from a gm repair guy that the dryers occasionally come apart on the inside and need to be replaced. So we also replaced that. I thought maybe I had a faulty control panel and so I switched out with a friend that had the same control panel and still didn’t have any luck. I don’t think it’s the compressor because there are a random times that it will work all day and not ever have a problem. Any help would be much appreciated.

I will look for S.I.'s but you are going to have to post system pressures both when working good and when these problems occur,you don’t mention orfice tube replacement,its easy,look for LOTS of metal on the screen.

Its not a dryer, its a accumulator on GM trucks.

I had a similar issue with a 1990 Ford Aerostar. The problem turned out to be the fan clutch. Apparently, the fan didn’t turn fast enough to pull sufficient air through the condenser, but did pull enough to keep the engine from overheating.

The techician pinpointed the problem by doing the following: 1) attached the gauges and watched the gauges as the air conditioning was on. When the gauge showed a higher pressure than normal, he found that the air conditioner wasn’t blowing cold air. He then directed his shop fan into the grille of the Aerostar. The gauges returned to normal pressures and the system began blowing cold air.

I don’t know whether your Chevolet Silverado has an electric radiator fan or a mechanical fan with a clutch. However, if the fan isn’t pulling sufficient air through the condenser, there will be a problem.