AC blows hot air
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On The Tree
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AC blows hot air Hey guys my ac blows warm air. I was about to put some r134 in, but I read that r134 with the leakage blocking addictives aren't good for the system. I was wondering if I should just try to run some dye and see where it's leaking from? I also read if I had to replace a line or whatever is leaking I have to flush all the oil and r134 that's in the system now. How would I go about doing that? Should I just test my luck and fill some r134 without the leakage blocking additives?
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From: Maricopa, AZ
AC blows hot air Trending Topics
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From: Maricopa, AZ
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If the A/C isn't working it's one of the following things.
Fuse
Relay
not getting power/ground to the A/C compressor due to a wiring problem
A/C clutch is toast
A/C compressor is toast but the clutch will still engage
orfice tube is full of trash due to the compressor coming apart or the descent bag in the accumulator
pressure switch has failed
no/low freon in the system and the l/p switch is preventing the compressor from coming on.
Thread Starter
On The Tree
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I found the ac clutch in front of the compressor and it's rotating so I'm guessing it's working right? It's not making any unusual noise either. I couldn't find the air bend where under the dash is it? Passenger or drivers side?
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AC blows hot air It's buried, you need to remove panels to find it. Best to just adjust the control **** and see if the temperature changes.
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On The Tree
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So if I wanted to check the orifice tube I would need to drain whatever freon is left right? Should I just add freon in and see what it does? How do I tell if the compressor is bad? I went to auto zone and the guy told me the gauges wouldn't be to accurate if there was oxygen in the system.
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On The Tree
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Ok so I officially gave up on trying to fix it. This is the first time I haven't been able to fix something, but then again I have no clue about ac stuff. So I'm going to have it diagnosed and try to fix it again.
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AC blows hot air Put a proper manifold gauge set on it with the car off, note the pressures on both gauges (they should match or be very close to matching), also note the outside temp. Start the car and rev the engine to 1500ish rpms, note both gauge pressures. Post up the results of you can. Don't worry about air in the system at this point.
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On The Tree
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Put a proper manifold gauge set on it with the car off, note the pressures on both gauges (they should match or be very close to matching), also note the outside temp. Start the car and rev the engine to 1500ish rpms, note both gauge pressures. Post up the results of you can. Don't worry about air in the system at this point.
On The Tree
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From: Mesa, AZ
If your compressor is working properly after a few minutes that silver can looking thing on the passenger side of the engine bay will get icy cold and frosty, even if your blend door in the car in not working. A properly working Ac will read 30-45 psi on the low side depending on the outside temperature WITH THE CAR RUNNING and AC ON MAX. After you shut it off and wait a few minutes the pressure will equalize between low and high side so if you shut your engine off and the reading jumps up to 60-75 psi for example and it drops down again with the engine running it means your compressor is doing what it is suppose to. The vent temperature on MAX AC should be roughly 30 degrees colder then the outside temperature, AC will be less effective in high humidity environments then it will be in dryer climates as it removes heat and moisture from the air. If for some reason you got air or moisture in your AC lines a reputable shop will have to draw a vacuum on your system and recharge it properly which usually runs around $100. I would personally buy those AC recharge cans for $25-30 with the pressure gauge and check it yourself first. If it is just a little low I would give it a few shots of R134a and let it run a few minutes and then recheck the pressure. If that doesn't work I would take it to a shop for a proper diagnosis. AND DON'T OVERCHARGE OR FILL IT TO HIGH!!! It's better to be a little low then to high on pressure, if you severely overcharge it you can wreck your compressor and cause major problems. So be patient and wait and check pressure carefully before adding more refrigerant into the system 
Last edited by McGinnis; Aug 22, 2015 at 01:53 AM.