a/c help

[Gregory w Bender]

I am trying to recharge the a/c on my explorer. The guy who had it before me took all the refrigerant out and put plain air in it. I let all the air out and tried to put refrigerant back in it put it won't blow cold air. I did what it said on the bottle and nothing happens. I rock it from 12pm to 3pm upside down. The pump kicks on then runs for about 3 to 5 seconds with the a/c on max. It just keeps blowing warm air. The switch on the low side kicks the pump on at 35 to 45 psi and off at 20 to 25 psi. I watch the gauge on my refill can. Now does anybody know What the psi should be when off or running? Right now when off the psi goes up too 55 psi. There no leaks. Hope someone can help. Thank you for the help.

 

[poker4me007]

How much refrigerant did you put in?
There should be a label on the radiator support saying how many ounces the system holds.
Too much is just as bad as not having enough.

 

[Mbrooks420]

If there was air in the system for any amount of time, it’s probably ruined. Did you use a proper vacuum and hold it under vacuum for a period of time? Or just let thenpressure out?

 

[1998Exp]

If there was air in the system for any amount of time, it’s probably ruined. Did you use a proper vacuum and hold it under vacuum for a period of time? Or just let thenpressure out?

To my knowledge, not ruined, but the accumulator/dryer will have to be replaced. And yes, the proper way to recharge is to pull vacuum for some time first, not to mention that filling should be with the indicated amount. However, the better question is why the previous owner evacuated the system. Unless he was replacing something unrelated (radiator, for example) that required disconnecting refrigerant lines and just decided to leave it like that (unlikely), I would guess that the system was not operational to begin with.

 

[Mbrooks420]

If it’s been attempted to run for any amount of time with moisture in the system I would not expect any sort of easy fix.

 

[Gregory w Bender]

I let the pressure out then started it up with a/c on max and where the pressure switch is on the low side and unplug it and took a wire jump it cross to let the a/c pump run to circulate anything in it and then i let what pressure build up out of the low and high side. Then i plug the switch back in and started it back up with the a/c on max put the Freon in to where i read it online to the psi it should be at. The pump with kick on but for like 3 to 5 seconds then kick off. After it get back up to 35 to 45 psi the pump kicks on the after it gets down to 20 to 25 psi the pump kicks off. I get no cold air.

 

[Mbrooks420]

That’s not even close to kosher. At the very least you will need to evacuate the entire system, and hold a vacuum on it for a considerable time. After replacing the accumulator, and orifice tube for good measure. Then you need to charge it with the correct volume of Freon.