Results 1 to 2 of 2
  1. #1
    Join Date
    Oct 2003
    Post Likes
    0 Post(s)
    0 Thread(s)

    condensation on supply planum and air duct, mold? what to do to fix?


    i am suspecting a mold issue with HVAC which is 3 years old. I am in DFW. It's 4 ton split system. Trane. the evac coil is in the attic.

    Recently i smelt something unusual in rooms supplied by the same duct and looked for air leak but didn't find any. Then it became musty and I have irritating throat and headache and started suspecting mold.

    My supply planum is always wet when it run below about 95 degree when attic is not very hot. Especially where it is connected to evac coil box. Also the air duct is leaning again part of the planum and other air duct and surface of the air duct and planum have moistures. The air duct with moisture is the one supplying air to the room with smell. All(5) of the ducts from the planum have dampers and 2 of them are nearly closed.

    I have complained this before when the unit was installed. However, he told it's quite normal to see some condensation even thought it drips to the pan and I have a puddle all the time unless it's above 95 outside or some

    I am not sure if I need to call original installer but not sure what I should ask him to correct if there is anything he can correct. The warranty is over for labor. I guess I could call another company but need some ideas.

    I need some advice what I should ask to look to fix condensation issue. or is it just normal?

    if there is mold, where do you look for? The smell is coming from one duct. I am not sure if that's mold or just air leak even though i looked around. where would you look?. if there is a mold what would you do to remedy it?

    Thanks for reading.

  2. #2
    Join Date
    Jun 2003
    Madison, WI/Cape Coral, FL
    Post Likes
    0 Post(s)
    0 Thread(s)
    Condensation on the outside of an attic duct requires more insulation with an exterior vapor seal is needed to raise the the temperature above the dew point in the attic.
    We assume the a/c is cooling the home and maintaining 50%RH. Measure the temp/%RH of the air in the space and and a/c supply. Report and we will comment.
    If the the air flow is very low, not enough air flow, the supply temperature may be too low. Adjust the air flow to change the supply temperature.

    Your installer is the place to start.

    Keep us posted.
    Regards Teddy Bear
    Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
    Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
    Use +Merv 10 air filter. -Don't forget the "Golden Rule"

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Contracting Business
HPAC Engineering