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vent condensation

Not saying that it could not happen it just, I have not seen

It possible that you have some leakage from the attic around
the return pleum.Hot humid air hitting a cold metal surface.Thats possible.

Other then not really knowing where your system is install
and how well its performing all we can do is guest at best
at what the problem could be.

Maybe a pro with good testing equipment and psychrometric
chart could point you in the right direction.


  • earl the pearlearl the pearl Member Posts: 2

    i have a ceiling register that drips condensation when the cooling system is running. what is causing the problem and whats the best fix?
  • don_192don_192 Member Posts: 45
    Not in order

    Pour airflow,not enough duct wrap on your ducts.Ducts not sealed.Condensate blowing off the coil.High inside humidity.

  • Brad White_9Brad White_9 Member Posts: 2,440
    What Don Said

    All of those factors can contribute.

    One factor to expand upon is the "poor airflow". If the volume moving across your coil is too low (think: clogged filters,where is the cat...?) the air coming off the coil will be sub-cooled too far below the dewpoint of the ambient air. Instead of supplying 52-55 degree air you might be introducing 35 to 40 degree air. Thus the surface of your grille will be down there in temperature, like a cold glass of beer on a humid day.

    The low airflow prevents good turn-over to condition and dry the space. I would hazard a guess that this occurs mostly during start-up when you are trying to pull down the temperature from a warm set-up unoccupied temperature.

    Random Drive-By Thinking,

  • earl the pearlearl the pearl Member Posts: 2

    this is a return register. does that make a difference?
  • Brad White_9Brad White_9 Member Posts: 2,440
    What I am thinking now is

    that your condensate pan is overflowing back down your return duct. Don is right again, that is odd. Return air is, by definition, room temperature so if that is humid enough to condense, you have bigger problems!

    I would check the ductwork, drain pan, area below the air handler... I cannot believe the grille moisture is primarily condensing on the grille itself.
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