How To Replace a Bathroom Fan
"Panasonic's Flex-Z Fast™ bracket makes installing a new fan surprisingly simple."
Materials
Today, we’re replacing an old, noisy bathroom fan with a newer, quieter fan that will last for years to come.
Our old fan was an inexpensive, contractor-grade bathroom fan that has worked fine over the years, but clocks in at 81 on the decibel scale, which is pretty loud. We’re going to swap it out for Panasonic’s WhisperFit fan. After running a test, we found the WhisperFit provided a noticeable improvement in sound—when we measured with a decibel meter, the WhisperFit registered around 13 decibels lower than the old fan on the highest setting.
Gather your materials and let’s get started!
Step 1: Disconnect power
Before you begin, make sure you’ve disconnected power to the existing fan by shutting off the circuit breaker. This may cut power to the lighting in your bathroom, so you might need to grab a flashlight, work light, or headlamp.
Then, remove the tape placed on the damper and adapter before beginning the installation process.
Note: Please wear gloves during the installation process. As you can see, we forgot this step, which is a safety hazard. You'll also want to keep the installation instructions handy—we reference them throughout the following steps.
Step 2: Remove existing fan
Once the power is off, start by removing the grille of the existing fan, which is likely held in place with a spring clip. Gently pull the grille down from the ceiling and reach into the hole to unfasten the clips. This will expose the fan housing, which is likely attached to a separate perimeter frame.
Unplug the fan housing from the ceiling and use pliers or a small pry bar to separate the fan from the frame. Before disconnecting the wires, be sure to mark the white, black, and green ends that extend from the housing—you’ll need these to connect the new fan.
Find the fan's exterior exhaust fan duct, disconnect it, and put it aside (you'll reuse this).
Step 3: Install Flex-Z Fast™ bracket
Next, install the bracket onto the framing above the ceiling. The hole for this new fan will need to be a bit bigger than the old one. Our Panasonic fan includes a cardboard template that allows you to mark the new fan’s size on your ceiling, so you can easily adjust the size of the hole.
Align the template against the side of the existing hole directly below the rafter. Double-check your placement, tape the template in place, and then draw through the slots in the template to mark the perimeter of the new hole. Take your time here and make sure the placement is right before making any cuts; when you’re happy with the placement, use a drywall saw to cut the new hole to size.
The cuts for the new hole don't have to be perfectly smooth or exact because the grille will overlap the hole by an inch all the way around and cover the edges of the hole you make.
Panasonic’s bracket folds, so you can easily insert it through the hole in the ceiling and then open it up again for mounting.
Clear away any loose insulation from the top of the drywall and position the bracket with the screws against the rafter at the hole’s edge. Extend the bracket to the neighboring rafter and secure with two pre-threaded screws.
Step 4: Connect exhaust duct and wires
With this Panasonic fan, the wiring box and duct outlet are separate from the fan body, which makes this step easy.
Take the flexible exhaust fan duct pipe and connect it to the 4" outlet on the fan. If you have a 3" pipe, use the adapter included to size it down.
Now connect the wires from the fan body to the box. Refer to the wiring diagram in the installation instructions, and be sure to match up white to white, black to black, and green to green (or, in our case, copper to green) wires. Then, secure with wire nuts.
Fasten the exhaust fan duct to the fan’s outlet and secure with tape or clamps. Then, place the connected exhaust duct up into the hole above the ceiling and secure it to the bracket using two screws, which are provided.
Drive the screws vertically up through the exhaust duct and into the holes in the bracket.
Step 5: Install fan body
Find and align the guides on the exhaust duct and push the fan body straight up into the hole. The body will click into place where it meets the mounted duct and wiring assembly.
Included with the fan is a short screw. The spot to place it is clearly marked on the fan body, and it’s easy to drive into place making an electrical ground between the fan body and the exhaust duct.
On the side opposite the exhaust assembly, find the holes in the Flex-Z Fast™ bracket. Grab your driver and drive two more screws vertically through the holes in the fan body up into the bracket. Now your fan is securely mounted.
Step 6: Attach fan grille
Switch the circuit breaker back on to restore power to the fan. Turn on the wall switch and check to make sure you can see the fan’s squirrel cage spin—this will indicate that the fan is working correctly.
Lastly, attach the grille using the spring-wire clips on either side. The new grille fits easily into place with a spring wire clip on two sides. These clips will hold the grille securely against the ceiling.
And that’s it! Six simple steps to a quiet, high-quality fan that will last for years to come.
For more home improvement tutorials, check out how to rain-proof outdoor stairs and seal up drafty doors.
