The sizes of my AC high and low pressure ports reversed
#1
Van
Thread Starter
The sizes of my AC high and low pressure ports reversed
I have a 89 f150 that has been converted to 134a. Anyone else find the port sizes reversed. Hooking up mt AC guages the red high hose will only conn to the low side and visa versa.
#2
Senior Member
Ports were installed wrong, IIRC the former R12 fittings were the same size, so likely just wasn't paying attention when the R134 fittings were installed on top of the R12 fittings. If the gauge set has the same scaling range, probably would never notice.
Brings up a question of whether the guy who did the conversion knew what he was doing, or are there other surprises in store...? This could be a serious issue if trying to add freon, and one is not aware of this error!
Brings up a question of whether the guy who did the conversion knew what he was doing, or are there other surprises in store...? This could be a serious issue if trying to add freon, and one is not aware of this error!
#3
Van
Thread Starter
The aftermarket 134a high and low ports can't be reversed to correct this as the threads are different diameters and will only install one way. With the larger on the low side and smaller on the high side. I would like to correct this. Are the valve diameters an industry standard or do they vary by brand or make? Do the adapters come in different sizes? If so I can't find them.
#4
Van
Thread Starter
I have a answer.
The larger thread 7/16 is the low side the smaller is 3/8 and is the high side. The wrong adapters were installed. I found the correct ones online