Window fans help to cool down rooms when you do not necessarily want to turn on the air conditioner. The Holmes window fan simply sits inside the window frame using the operating window to hold it in place. When the fan is left in the window for long periods of time, dust and dirt build up on the fan blades and motor. The dirt and dust eventually cause poor performance and might even damage your fan. Cleaning a Holmes window fan helps to ensure that the fan operates at peak efficiency.
Unplug the Holmes window fan power cord from the wall outlet. Pull the window open enough allow access to one side of the fan.
Press the locking tabs on the top and bottom of each end and compress the extender panels toward the fan. The extender panels are the side panels on each side. Pull the fan completely out of the window.
Remove the screws securing the front and rear grilles to the Holmes window fan with a Phillips-head screwdriver. Pull the grilles away from the fan enough that you can access the fan blades. Do not pull the grilles off the fan, as removing them completely can cause damage to the retaining clips.
Spray compressed air over the two motors from behind the fan. This removes built-up dust on the motor and spindle.
Dampen a clean cloth with warm water and wipe the blades and the grille down with the cloth. If there is heavy dust buildup, it might be necessary to rinse the cloth and wipe the blades and grille down several times.
Press the front and rear grilles back into place and secure with the retaining screws. Fully extend both side panels and wipe them down with a damp, clean cloth. Reinstall the Holmes window fan into the window.