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2012 Ford F-150 AC not cooling


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2012 Ford F150 ac not cooling. Pressure reads 15 on the low and 150 on the high. Takes about 30 to 40 minutes to equalize after shutdown. Expansion valve maybe? 

Clarification: what is the ambient temperature for those readings?

About 75 to 80 degrees.

2 Answers

On the face of it seems like it's undercharged. Have you checked for leaks?

No leaks


Looking at pressure charts for the temperature range you gave, I agree with @chucktobias, it seems to be undercharged. 35-50 PSI low side and 150-210 PSI high side is are the pressure in ranges in that ambient temperature. That wouldn't be unexpected. It's a 10 year old Ford and if the A/C has never been serviced, it's probably low. They all leak very slowly over time. Scotty's mentioned that several times.  

If you're familiar with using manifold gauges to add refrigerant, you could add some R-134a to the system. Bring the pressure to roughly the middle of the range for the ambient temperature to see if the cooling capability improves. There's no real way to tell how much refrigerant is in a partially loaded system unless you have pressure/ temp charts for an exact system. Make sure your can of R-134a is straight R-134a, no stop leak. Those can destroy the system. Properly recovering, pulling vacuum and refilling with the exact weight on the hood sticker should restore the cooling capacity, providing it's not open anywhere.