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Discussion Starter · #1 ·
hey i have a problem, my ac is blowing only hot air. the compressor cycles and everything, the glass peice that you can see the freon through is clear and not bubbles, but you can see the freon moving. i checked the fuse and it good.

have anyone ever experienced this before??
 

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It's possible you might have a leak somewhere in the system. The system has to be evacuated and recharge with dye. Once this is done, you have to use the ac for a few days. If it start to blow hot air again, then the system has a leak and the dye will pin point where the leak is by using a special light. If it blows cold air then you're ok...system probably just needs to be charge.
 

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Discussion Starter · #4 ·
Gray Rider said:
It's possible you might have a leak somewhere in the system. The system has to be evacuated and recharge with dye. Once this is done, you have to use the ac for a few days. If it start to blow hot air again, then the system has a leak and the dye will pin point where the leak is by using a special light. If it blows cold air then you're ok...system probably just needs to be charge.
i understand what you are saying, but i can see the freon moving and there is no bubbles in it, that means the system is charged, so i dont think i have a leak.
 

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2pac, it's no longer freon :) ......it's R134 now. You might see the gas moving thru the sight glass but it might not be enough to make it blow cold air. The system usually holds about 2lbs of R134.
 

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you could have just lost pressure if there isnt a "minimum pressure" in the system the compressor doesnt come on.

Does the A/C clutch engage ? IF your car is 3-4yrs old and u used it often you may be just running low. I seen that happen on Lifeas0ne car. He recharged R134 and he's good to go.
 

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can you actually hear the pressure switch turn on the compressor?

refrigerant r12/ r134. grayrider is right r134 is ozone friendly or cfc safe and that is waht is used on our cars.
 

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Discussion Starter · #10 ·
BigDaddyRich said:
you could have just lost pressure if there isnt a "minimum pressure" in the system the compressor doesnt come on.

Does the A/C clutch engage ? IF your car is 3-4yrs old and u used it often you may be just running low. I seen that happen on Lifeas0ne car. He recharged R134 and he's good to go.
BDR, the clutch does engage, the revs on the car drops like usuall and the fans come on. it would run for a while then go off then come back on again.
 

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Discussion Starter · #11 ·
2TGEU said:
can you actually hear the pressure switch turn on the compressor?

refrigerant r12/ r134. grayrider is right r134 is ozone friendly or cfc safe and that is waht is used on our cars.
i know that it is R134, i am just use to calling it freon. but you all knew what i meant
 

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if your comp still turns on then, you do have a leak somewhere in the system whether the cooling coil, condenser or piping do a leak test whatever residual refrigerant you have left is insufficient to cool the evaporator. btw deter from switching on the compressor to avoid wearing it down too, since it will continue to turn on as the stat will keep on wanting to reach the temp setting but to no avail.
 

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OK there is a pressure switch on the line.

Now if your only getting HOT air. check the blend door to see if it is stuck. Now another key thing to look for is to see if there is any moisture comming from the drain hole.

Given your saying the compressor cycles on and off usually thats a sign of something else wrong. To be honest you cannot really diagnose the problem here online. You will need to get some pressure readings to see whats going on there. And PLEASE do not get the R134A from the store with SEALER.. IF your local hit me Up I have everythign needed. to work on it.
 

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2pac said:
, the glass peice that you can see the freon through is clear and not bubbles, but you can see the freon moving.
Sounds to me your low. On a full system you will see a constant white could.
 

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Discussion Starter · #15 ·
i took it to the dealer this morning, will post an update as soon as i get one.

thx for all the replies.
 

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Just bought an 04 2 days ago and this exact thing happened to me. checked the system for leaks, purged it, refilled with r134, still blowing hot air. Its not even just not cold air, its full on heat. I dropped it off at lexus and will report back with what they find. Compressor works, clutch works, and full of refrigerant so im leaning towards some type of sensor. I dont know enough about these cars yet to pinpoint it.

(bump from the dead i know but figure someone else may end up here from google)
 

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If everything is working and it's charged up to the proper amount sounds like you have a stuck blend door. It's a door that shifts the area in the direction it needs. If it's stuck in one position it'll blow the air through the heater box instead and give you hot air. If you're not even getting warm or cool air but straight up hot that's the most logical explanation. I can't tell you if they're electrical (I believe they are) or vacuum operated. It's also not uncommon for something to be lodged in there. A pen, lighter, pencil, twig etc. I've thought the blend door motor was bad on a few occasions and pulled out a pencil.
 

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yeah, most logical explanation is air mix door or air mix servo. air mix sensor is electric and can be heard when changing temp from low to high.
 
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