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Re: 1979 F150 will not cool below 60F register temps/evap partially warm*FIXED*

Posted: Mon Sep 07, 2020 7:39 pm
by jcamp2112
So today on suggestion from many, I replaced the evap and recharged. Still had the same issue, 60f outlet temps no matter the charge level. Decided to change one more time the expansion valve, vacuum and recharge. This time, I got outlet temps of 42F which is perfect. Guess the TXV I had wasn't the right one, because this one works perfect.

Also come to find on this application, the evap lines feed into the bottom in 3 pairs, and they come out the top. So having a super cold bottom, and warmer top of the evap is normal.

Really happy I fixed this, just sucked it took me the whole summer to get to the bottom of it though lol... Thanks for all the help folks. This is a great forum.

Re: 1979 F150 will not cool below 60F register temps/evap partially warm

Posted: Tue Sep 08, 2020 1:25 am
by Al9
So you basically had a nearly jammed closed TXV that starved your evap big time (hence only 10% of the evap cold).

That's why i'd use either Denso or second hand TXVs only, if OEM ones weren't available/were made of diamond.