Condensation on Ductwork
If your ducts are in the crawl space or unfinished basement you probably have some condensation on them when your air conditioner is running. This is not indicative of an equipment problem, but rather, a problem with the building envelope.
Whenever the surrounding air is warmer and more humid than the air within the duct system, condensation may occur. A typical example would be a glass filled with ice water that will sweat on the outside when sitting on a counter. A psychrometric chart can actually pinpoint when condensation will occur.
If your ducts show any condensation, try some of the following tips:
- Seal and insulate all crawl spaces from outside air.
- Make sure your A/C is not oversized.
- Insulate the duct.
- Install a professional grade dehumidifier which would be the best solution.