Airconditioning Compressor Cycles

[raffi]

I have a 1995 GMC and the air conditioning compressor cycles when i turn it on. I have a cheap gauge and freon mixture. I bought at wall mart. Any way when i plug it into the the high side the pressure reads between 25 and 45 psi. As i run the ac and the compressor truns on the psi gos down to the 25 and kicks out. Once the compressor turns off the pressure rebuilds and the compressor turns on again.The air temp is cold but not as cold as it use to be. What do yoou think i need to do.

 

Thanks

[Jsdirt]

If your talking about those single gauges that come with the cans of 134a at Wal-Mart, be very glad you did not hook that to the high-side. You'd be in the E.R. rather than on this forum!

 

Sounds like it's thankfully hooked to the low side ... and if it drops to 25 psi when the compressor kicks on, that's good. But you cannot diagnose a problem without both HI & LOW side gauges connected to their respective lines.

 

If you want it to cool better, first check for debris between the radiator & condenser. Then make 100% sure the fan clutch is good to go. If it's never been changed, change it anyway. Genuine GM - no aftermarket stuff in this case. Then with the appropriate double gauge set you can get your high & low side readings to determine if your low on charge, also taking ambient temperature into account. Short cycling usually indicates a low charge. Low charge usually means leaks ....

[Zembonez]

Reading between the lines a bit here... If the compressor cycles rapidly, it typically means that there is not enough charge in the system and the low side is dropping low enough to trigger the low pressure switch, which turns off the compressor to avoid damaging it. I agree that the only way to really know what the system is doing is to hook it up to a proper high / low gauge set.

[raffi]

Thanks for the quick reply's. I think hats the best i can do. I'm going to have to take it to an AC shop and have them check it out. By the way i did change the clutch many years back. Is there any way to test the clutch before it gos to the AC shop. Those guys usual start at $150.00.

 

thanks

[Zembonez]

Thanks for the quick reply's. I think hats the best i can do. I'm going to have to take it to an AC shop and have them check it out. By the way i did change the clutch many years back. Is there any way to test the clutch before it gos to the AC shop. Those guys usual start at $150.00.

 

thanks

TYPICALLY if a clutch goes out, it just won't engage at all. What you describe sounds like a system with a small leak somewhere. Hopefully it doesn't turn out to be anything expensive.

[minibike132]

Thanks for the quick reply's. I think hats the best i can do. I'm going to have to take it to an AC shop and have them check it out. By the way i did change the clutch many years back. Is there any way to test the clutch before it gos to the AC shop. Those guys usual start at $150.00.

 

thanks

TYPICALLY if a clutch goes out, it just won't engage at all. What you describe sounds like a system with a small leak somewhere. Hopefully it doesn't turn out to be anything expensive.

 

 

 

+1 It's most likely a little low.

 

DO NOT ADD R-134 THAT HAS LEAK SEALER IN IT!!!!!!!

 

Find the leak and fix it right or add every so often but do not add leak sealer.