A/C cools for about 20 minutes, then slowly warms up to 70 degrees coming out the vent. We shut off the truck for 5 to 10 minutes, and restart and A/C cools again. It has been working intermittently for years and we would like to get it fixed. Need some help, summer coming!!

 

Sounds like it is freezing up. Whens the last time you had it checked or refilled?

 

Also check the AC drain off of the HVAC box. The drain is visible after crawling under the van and looking up just behind the fan side of the box. Use something thin and round to gently push up the hole and see if water drains out.

Low freon can cause the system to freeze up and act intermittently.

 

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