A/C system just keeps blowing hot air

RHOADES21

MEMBER
2004 CHEVROLET TAHOE
5.3L
V8
4WD
AUTOMATIC
234,000 MILES

I have the vehicle listed above z71. The tensor pully was replaced and we just recently replaced the compressor then recharged the system and it is still blowing hot air. We let pressure out and then recharged it and it is still not blowing any cold air, nor is the compressor kicking in now. It has the front and rear A/C and the 3 control units. Not sure what else to do with it.

1 Reply

JIS001

MECHANIC
3,408 POSTS

Anytime you have the system open you will want to do a vacuum for at least 30 minutes to get any moisture out. Here is a link on the procedure:

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Try to vacuum the system out first and then recharge the system.

Also this guide shows how to check the system pressure which we should do after you evacuate it and pull it into a vacuum then recharge it.

The chart below shows what proper pressures are when the compressor is engaged.

So I would suggest if the compressor is not coming on, jump the relay to get it on and check the pressure. Once the pressures are correct and the compressor is still not coming on, we can figure out the electrical side of it.

However, there is a chance that you are never getting enough freon in it to get the compressor to kick on.

Once you jump the relay it will pull the freon in and fill the system properly based on pressures.

Let us know what you find with this. Thanks

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