How to Install an Inline Duct Booster Fan

Locate where in the existing duct system the duct fan will go. Verify the size of the duct and get an inline duct fan the same size.

Remove the HVAC tape and disconnect the ventilation duct at one of its joints. Connect the intake end of the inline duct fan and connect it to the supply side of the ventilation duct. This should be so that the intake side of the fan points towards the air handler.

Connect the output side of the fan to the distribution side of the ventilation duct. This setup should have the output of the duct fan directed towards the area that needs the additional airflow.

Place HVAC sealant and HVAC tape around both ventilation duct joints. Plug the electrical cord of the duct fan into the outlet on the stand alone thermostat.

Drill two pilot holes and bolt the thermostat to the ventilation duct. Run the black and white wires from the thermostat to the junction box that will provide power to both the fan and the thermostat.

Shut off the power at the main power panel for that particular junction box. Remove the junction box cover and remove the plastic twist caps on the white and black wires. Connect the white wire of the thermostat to the white wire group of the junction box. Then connect the black wire of the thermostat to the black wire group of the junction box.

Connect the ground wires also, if the thermostat is equipped with one. Place new plastic twist caps on each of the two or three splices. Replace the junction box cover and turn the power back on.