Condensation On Attic Fan Damper

The duct is not kinked but there is a 1 5 inch gap between.

Condensation on attic fan damper.

The outside damper is stuck. First inspect the damper on the outside. The damper will help prevent cold air from dumping back down into the house which may lead to condensation right at the fan itself. The duct should not be aimed at a roof vent or have any loose.

There s a damper on the fan housing too but the outside damper is much more likely to stick. Whether you use your bath fan or not some warm air will still escape into the ducting. Find the vent hood on your roof or exterior wall. If your ducts are properly insulated another potential cause of condensation is lack of use.

Attic air leak into the fan unit unitself from not being well sealed to the ceiling attic floor exhaust damper not opening properly so humid exhaust air doesn t exhaust and stays in the duct getting cold enough to condense and drip back down. Bath fans have a damper designed to keep the outside air from entering in through the fan but that valve doesn t stop warm air from escaping. It should open only under pressure from the warm air to let it out and remain closed the rest of the time. The exhaust vent in the powder room downstairs is fine this is a new thing.

The attic is now pleasant as well just a few degrees warmer than the house. Exhaust fan condensation drip.