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Posted

Ok here's hat my ac is doing after I replaced the system compressor, condenser, hoses an expansion valve it worked good then started warming up I replaced my temp sensor an it went back to normal now it only seems to cool when the truck is up to operation temp .it's I start it from cold it will not cool under the truck is hot , but another strange thing is it seems to work better in the morning than at noon an the ac compressor is always running even when its not cooling seems like as the day gets hotter the longer it takes to work. An freon levels r good I can only check it when its actually cooling. So any help would be great im at a total loss here.

Posted

Welcome to the forum! Is it possible the system has too much freon? Over charging reduces system efficiency. I agree with sid, Put some gauges on it and make sure the fans work and are blowing in the correct direction. Come back and post the pressures along with ambient temp and rpm and we will have a better idea of what the problem may be

Posted

Two Quick checks:  The Low Pressure line from the  evaporator to the compressor   should be very  cold. If not there is  a refrigeration problem either  with the  refrigerant or the  equipment.  Also verify that you are getting a vigorous  flow of air  from the  dash vents to insure  that  that  system is  functioning  as it  should.  Good  Luck

  • 2 weeks later...
Posted

Hey guys  thanx for the help I haven't put guages on it yet with work an all but got some time off for the 4th so ill look then but the fans don't come on like they should on start up with ac on only when the truck reaches temp does the fan come on then it seems slow not as fast as I think they should

Posted

Does the ac function as designed? The fans should come on when the designed head pressure is reached. If not the compressor will shut off due to high head pressure.  

 

Flip side is the fans will turn on as stated- when the engine tells the ecm.

  • Like 1
Posted

Yes I believe it all works as it should ac compressor kicks on even when it's not cooling an during this time the fan won't run an ac pressure are jus off the charts

 

Posted

If the fans do not run you can have the proper charge and it will not cool, unless the truck grill has air flowing though it. I would say the ac pressure switch is defective,  but we have seen guys swap them out to no aval.

 

Here are my pressures for today. I used an old blower from a residential Furnace to blow air across the condenser. The truck fans came on at a low speed then medium. Never made it to high speed.Do not mind the two different gauges. The analog are my backup. Vent temp is noted on the first pic, suction line temp on the second. 

20240706_143134.jpg

20240706_143129.jpg

20240706_142940.jpg

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