Long Runs Need a Dryer Vent Booster Fan
Booster fans are specially designed to solve the problems caused by long dryer vent runs. A pressure sensitive switch automatically starts the dryer vent booster fan only when the dryer is running. Hot air from the dryer is then pushed out the exit. Booster fans should be added to any dryer duct exceeding 25 feet in length. When calculating the length of your vent every 90 degree turn is equal to five feet in length. Example: a 15 foot long vent with two 90 degree bends = 25 feet according to FL building code 504.6
According to the booster fan owner’s manual the fan should be removed and cleaned every six months. Unfortunately this can be a big job depending on where your fan is located. We go to homes all the time that has a non working fan due to neglect. The most common dryer vent booster fan we see is a Fantech priced from $175 and up not including installation.