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  1. #1

    Default A properly running AC system question

    If an AC system has a new compressor, orifice, dryer and high pressure line, correct amount of refridgerant and the engine also has a new fan clutch, when turned on max, would it drain water? I have seen my other vehicles do that with the AC running and after the engine is shut down, but my 97 Tahoe, with all of the aforementioned items does not drain water and when it is put on max AC, it blows only cool. Does anyone know what may be the cause of an AC system described above only blowing cool and and not cold? Thanks.

  2. #2
    stephan's Avatar
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    Two possibilities on the lack of drain water. There may not be enough humidity in the air to condense, or the drain hose could be plugged.
    As for not blowing cold air providing it's properly charged, the blend door may not be closed or adjusted properly & is mixing heated air with the AC
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  3. #3


    Yea the water is kind of a by product from the air, humidity levels will determine the amount of water.
    I'd check the drain lines, sooner or later you'll find that missing water and you might not like where it turns up which'll probably be on the passengers floor board of the truck.
    Again like Stephen posted check the blend door position this determines the temperature reaching the cabin.

  4. #4


    When using Max AC, you are recirculating the cabin air rather than drawing in fresh air from the outside. The perceived temp difference may simply be due to higher airflow across the evaporator. Try Max AC with the fan on low and see how cold it feels. As for no water dripping on Max, it won't take long to dry the air in the cabin, and the water will stop dripping. Once you go back to normal and draw in fresh air it should start dripping water again.
    When you hear hoofbeats, look for horses not zebras.

  5. #5


    Well, I live in Arizona, so zero humidity. Looks like I have to look at the blend door. Does that require dismantling the dash to access? Thanks for all of the replies.

  6. #6


    What kind of pressure reading are you getting on the manifold gauges, what is the ambient temp at the time of test, also did you check superheat?

  7. #7


    system was overcharged by .6 lbs of refridgerant. seems to working much better.

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