A dusty bathroom exhaust fan can still turn, but the clogged grille makes it move less air and leaves moisture hanging in the room. Cleaning the cover is a small maintenance job that can improve airflow without disturbing the fan housing.
Turn off power and remove the grille
Switch the fan off and use the bathroom switch only as a first step; for a removable grille, also turn off the circuit at the panel if you will reach near the motor. Pull the grille down gently, squeeze the spring clips, and support it with both hands.
Clean the cover and housing
Vacuum loose dust before washing the grille. Clean it with warm water and mild detergent, then let it dry fully. Use a soft brush or vacuum nozzle around the fan housing without bending the blades or pushing debris deeper into the duct.
Reinstall and check airflow
Replace the dry grille, restore power, and listen for rubbing or rattling. Hold a square of toilet tissue near the grille; it should draw upward while the fan runs. If airflow remains weak, the duct, exterior flap, or motor may need professional attention.
Keep it manageable
Inspect the grille every few months, especially in a frequently used bathroom. A quick vacuum prevents a thick dust layer from becoming a larger airflow problem.