Condensation On Attic Fan Damper

The exhaust vent in the powder room downstairs is fine this is a new thing.

Condensation on attic fan damper.

The duct should not be aimed at a roof vent or have any loose. Just as we were ready to move back in we discovered both bathroom fan exhaust ducts as well as the gas dryer duct all upstairs have been filling with condensation. If water drips from the bathroom exhaust fan the damper that normally controls the flow of air through the pipe may not be working correctly. The attic is now pleasant as well just a few degrees warmer than the house.

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. Whether you use your bath fan or not some warm air will still escape into the ducting. The outside damper is stuck. If the damper won t open the fan may drive enough air through the duct to cause condensation but not enough to warm the duct and dry it out.

There s a damper on the fan housing too but the outside damper is much more likely to stick. If your ducts are properly insulated another potential cause of condensation is lack of use. The duct is not kinked but there is a 1 5 inch gap between. Exhaust fan condensation drip.

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. First inspect the damper on the outside.