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Wrenchbender Ret · 09-16-2010, 04:40 PM

If you are using 134A it doesn't take as much coolant as R12 & naturally has more high side pressure. You may have too much in it. There is a special low pressure switch available for changeover. In real hot weather the high side pressure is going to be very high.

09-16-2010, 04:40 PM	#2
Wrenchbender Ret Registered User Join Date: Oct 2005 Location: Overland Park, Ks. Posts: 5,229	Re: Head Pressure building up If you are using 134A it doesn't take as much coolant as R12 & naturally has more high side pressure. You may have too much in it. There is a special low pressure switch available for changeover. In real hot weather the high side pressure is going to be very high.