Why You Need to Clean Your Bath Fan

I know from experience that it’s better to stay on top of home maintenance than to let stuff go. I keep a running list in my head of what needs to be done and spend my Saturdays attending to these various jobs. Anyone who owns a house can identify with this. It’s a perpetual job. Something is always breaking, wearing out, or needs some sort of attention, like a fresh coat of paint. Other things need cleaning, tightening, adjustment, or lubrication.

So I was shocked last weekend when I looked up and saw a bath fan grill covered with dust. I said to myself, “didn’t I just clean that?” The answer was yes and no. Time pressed, I had vacuumed the bath fan grills in the upstairs bathroom and the downstairs powder room, but I hadn’t removed the grills, cleaned and inspected the fan behind the grill­–like I normally do. A laundry room renovation and building a set of stairs (five stringers wide) on the back of the house had caused me to take some maintenance short cuts.

I said to myself, “I better have a look at that.” I turned off the fan, fetched a step ladder, climbed up and popped off the grill. I was shocked at what I saw, a fan motor and housing area almost clogged with dust.

Before I cleaned this bath fan, this is what it looked like.

I vacuumed the fan and surroundings clean and carefully inspected the wiring and motor for any dark-colored discoloration that could be a sign of overheating. Fortunately, everything turned out to be in good working order.

Nice and tidy. Here’s what the fan looked like after it had been brushed off and vacuumed clean.

Clean It or Regret It

The bath fan experience was sobering. It’s too easy when involved in big projects (that laundry room remodel and the stair construction project) to let other smaller maintenance jobs fall by the wayside. The maintenance on the bath fan was a small job; neglecting it was a big mistake. Although in this case there were no bad lasting effects, that’s not always the case.

Items like bath fans, dryer ducts, smoke detectors all require small amounts of maintenance administered at frequent intervals. Neglecting them for the sake of larger (and more enjoyable) projects can cost you.

Below I show the full sequence of steps to the simple job of cleaning out a bath fan. The job doesn't require anything more than the simplest of tools, a step ladder, a small shop vacuum, a nylon bristle brush, some spray degreaser, and shop towels. You may need a putty knife if the bath fan cover sticks to the ceiling by a layer of accumulated moisture and dust.

This what a typical bath fan grill looks like. It's a sure thing that the fan underneath needs to be cleaned.

Try to clean bath fans at least once a year. A telltale that the fan needs to be cleaned is an accumulation of dust on its surface.

Start by Removing the Fan's Cover

Two clips hold a bath fan grill to the metal box that houses the bath fan. Pull down on a side or on a corner, or use a putty knife to get behind the cover then pull it gently down.

Two Spring Clips Hold the Cover in Place

The bath fan grill (cover) has a pair of small plastic hooks molded into its back surface. The spring clips slip into the hook. Unhook the spring clip on one side.

With One Spring Clip Unhooked, Pivot the Cover Down

Pivoting the cover down gives you access to the second spring clip. Move it out from the plastic hook as you did at the first hook.

Use a Small Shop Vacuum to Clean the Fan

Work the nozzle of the shop vacuum over the motor, housing and wiring.

Use a Small Nylon-Bristle Brush to Complete the Cleaning

Use a small brush with non-damaging nylon bristles to gently scrub loose any remaining dust clinging to the housing, fan, motor, or wiring. Vacuum up any loosened dust.

Next, Clean the Fan Cover

Lay the fan cover (grill) on some surface that you don’t mind getting dirty and give it a thorough spraying with either a household cleaner or the same degreaser you use in the shop and garage,

Don't Forget to Clean the Back of the Fan Cover

Don’t forget to clean the back of the cover. Scrub both sides of the fan cover using the same plastic brush you used to clean the fan and its housing.

Pull the Spring Clips

Pull both spring clips and wipe off any dust or a light accumulation of rust from their surface. You’ll find that the cleaned clips will make it easier to slip under the hooks on the fan cover. Reinstall the spring clips.

Attach the Cover to the Clips

Slip the hook over the end of the spring clip and snap the clip into place. Do one side then repeat on the clip and hook on the opposite side of the cover,

Push the Cleaned Cover Into Place

With the fan and housing scrubbed clean, and the cover cleaned and dried, hook both spring clips onto the cover’s back and press the cover gently upward. Both spring clips retract into their slots on the sides of the fan housing and the cover seats flat against the ceiling. Turn on the fan and check for any rattling noises or something amiss (chances of that happening are small, but still you do want to check). The cleaned fan is ready for operation.

Roy Berendsohn

Senior Home Editor

Roy Berendsohn has worked for more than 25 years at Popular Mechanics, where he has written on carpentry, masonry, painting, plumbing, electrical, woodworking, blacksmithing, welding, lawn care, chainsaw use, and outdoor power equipment. When he’s not working on his own house, he volunteers with Sovereign Grace Church doing home repair for families in rural, suburban and urban locations throughout central and southern New Jersey.