When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
2002, F-450, 7.3 Diesel. A/C gas is R-134a. System is charged. After the A/C has been running for about an hour (max) and A/C air temp at the dash is about 40 degrees---the A/C output air slowly rises to about 60 degrees. Shut down the A/C for about 10 minutes--restart the A/C and output is back to 40 degrees. Live in Arizona--without A/C life is tough!!! What might be my problem and what might be the fix. I hate going to the repair shop without knowing what my problem might be and getting hosed for the fix!!!
How are the fins on your condensor? Take off the front grille shroud (actually easier than you might think) take a comb to the fins ( I can't remember, want to say it's 20 or 22 tpi) and get them all separated, maybe a thin flat screwdriver for areas of bird strikes
There will be a crap ton of sand pebbles in there as well. Then spray on a degreaser and rinse it out head on with water hose, a pressure washer can bend the fins back over if not directly straight dead on
Plus the obvious part of correct charge @ the correct ambient temp Ambient temp charge chart
Also check the air gap on the compressor clutch. It may just be starting to get worn enough that it starts to slip/disengage only after an hour. In fact, before you shut the AC off the next time this happens, pop the hood and look to see what the compressor clutch is doing.
I live in AZ and my A/C manifold hose had a crack in it, also the switch in the picture had a loose connection that would kick the compressor on/off randomly depending on how the plug was wiggled so I replaced the plug pigtail and it solved the problem.
Wes444
Learned something new from your post---all these years I thought the "radiator" directly behind the grille was part of the engine radiator--now I see it is part of the A/C system. Thinking this was part of the engine cooling, I cleaned it several time a year (with water hose) of bugs and dirt and straightened any bent fins on a regular basis. I see there were four (4) screws on the top of the grille, but there were four (4) clips on the bottom, a little hard to see and a little hard to get to. Since the condenser is clean----I saw no need to push my luck and break some plastic thing on the grille. Thanks for the info.
No problem
Not sure how the auto transmission setup is but on my ZF6 the order of cooling is the power steering cooler up front although at the very bottom, AC condenser, intercooler, followed by the radiator dead last to recieve fresh cool air.
I assume the auto transmission cooler is in front of the condensor
