Let's face the facts: Panasonic makes some of the highest quality exhaust fans on the market. And the Panasonic WhisperFit is no exception.
Not only is the WhisperFit extremely quiet, it is also very easy to install since it comes with a bracket that fits 16-inch or 24-inch joist spans.
It even comes with a tiny switch on the housing so homeowners can choose their own fan speed (50, 80, or 110-cfm) for it's efficient variable speed motor!
I decided to actually install the WhisperFit and provide original pictures and my thoughts on buying it. Let's get cracking!
When you open the WhisperFit shipping box, the instructions will be on the very top, along with the masking template and Flex-Z Fast Bracket. You will be able to see the 4 screws pre-installed into the bracket.
Once you remove the bracket and instructions, you can remove the white grille.
The bath fan housing itself is encased in foam inserts to protect it during shipping. There is some plastic on the center hub of the blower wheel which needs to be removed.
The two small machine screws are taped to the corner of the housing with blue tape. Likewise, the four longer screws are taped to the adapter with blue tape.
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50, 80, or 110
4-inch or 3-inch
0.3 for 50-cfm to 0.8 for 110-cfm
Masking & Cut Out Template
The Panasonic WhisperFit comes with a masking and cutting template for homeowners to use. The first function of this cardboard template is to trace the correct ceiling hole size during the installation.
Simply push out the cardboard along the perforated edges. Then put the template up onto the ceiling and use a pencil to draw out the hole perimeter.
Don't trace around the 'tabs' because those are only used for when painting. The cardboard template can also be used as a masking template to cover the ceiling hole if you desire to paint the ceiling.
Just put the cardboard over the housing (after you have removed the cover) and then fold in the two cardboard tabs into the housing so it will stay in place.
Flex-Z Fast installation bracket
The installation bracket that is provided by Panasonic (called Flex-Z Fast) makes installation pretty simple. This bracket has hinged sides so it will fit into the ceiling hole otherwise you won't be able to fit it into the ceiling.
Once the installation bracket is folded and inserted into the ceiling, simply line up the ends with the edge of the joists and screw it in place. The bracket has four pre-installed screws so you don't even have to look for the screws.
Adaptor (for duct and junction box)
The adaptor assembly is installed onto the installation bracket first before the housing. The adaptor is where the duct connects to and includes the wiring junction box.
Panasonic recommends connecting the duct to the adaptor with foil tape (or mastic) as well as the wiring before installing the adaptor. After connecting the wiring (using a stress relief) and securing the duct — you can proceed to install the adaptor with two screws. Homeowners will have to supply their own wiring stress relief or clamp.
The fan body is installed onto the installation bracket by sliding it into the adaptor while lining up the slots. Just make sure that the exhaust port is in the right direction.
It is secured by installing two machine screws on the opposite side of where the duct is located.
The motor and blower wheel can be removed from the housing in the future if you want to do a deep clean. You read our step-by-step guide on cleaning bath fans here.
4 self-drilling screws
The WhisperFit comes with 4 long self-tapping screws. Two screws are for installing the fan body to the installation bracket. The other two screws are for installing the adaptor assembly which is where the duct and wiring are connected.
1 machine screw (and 1 already on junction box)
There is one tiny machine screw which is used for 'grounding continuity' and basically creates a connection between the motor and housing. There is one other tiny machine screw that is pre-installed onto the junction box cover. This little screw will need to be removed in order to access the wiring.
4-inch to 3-inch Duct Reducer
The WhisperFit has a default 4-inch exhaust port. If it is possible, I recommend installing a 4-inch duct to get the most performance out of the WhisperFit.
Panasonic includes a 4-inch to 3-inch duct reducer so you can install a 3-inch duct if you desire.
The white grille is the part of the bath fan that goes over the fan body and covers up the bathroom fan.
It is installed by squeezing together the two mounting springs and inserting them into the plastic slots on the fan body.
Read Also >> What Are The Quietest Bath Fans On The Market?
Pick Your Own CFM (Speed Controller)
One of the most unique features of the WhisperFit is the speed controller that allows homeowners to pick their CFM or fan speed.
The speed controller is a small black box located on the top of the fan body and connects with it's own wire connection to the motor. The switch will be on the front near the top.
Variable Speed Motor
The motor is a variable speed (ECM) motor that can speed up or slow down to reach your desired fan speed (50, 80, or 110-cfm). This makes the motor very high quality and energy efficient as well as Energy Star certified. Read our guide on how much electricity bathroom fans use here.
Since all duct installations will be different depending on length, number of turns, and type of duct — having a variable speed motor ensures that you get the right fan speed.
Things To Know Before You Buy
The WhisperFit is designed for ceilings with 2-inch by 6-inch joists or larger. If you have a 2x4 ceiling (or 2x4 vertical wall), it won't fit due to the housing thickness.
Fortunately, almost all homes will have 2x6 or 2x8 ceiling joists, but you may want to check before buying the fan.
What You'll Need To Install It
- Electric or manual screwdriver
- Wire nuts or quick connects (connecting existing wiring to fan wiring)
- Wiring stress relief (to secure to junction box)
- Drywall saw (if you need to widen or make a new hole)
- Stress relief clamps
The white grille is installed by squeezing the mounting springs on each side. Once you squeeze the mounting spring, insert it into the plastic slot on the housing.
After completing the first spring, squeeze and insert the adjoining one.
Install Directly On Joist (Optional)
Another option is for homeowners to install the WhisperFit directly onto the joist.
I recommend using the installation bracket provided by Panasonic but installing it directly to the joist is an option if needed. There are holes on all four sides of the housing flange so it can be screwed directly into the joist.
The downside of this installation method is that there is no way to secure the other side so it will have to be free floating.
Wiring (Red, Black, Green)
Since there isn't a light, heater, or any other extras with the WhisperFit, wiring is pretty simple. Just connect white to white (neutral), black to black (hot), and the green for grounding.
Plug In Motor
Don't forget to plug in the motor. The wire connector will have to snap in place.
The plastic hook allows homeowners to slide in the bath fan onto the adaptor assembly without it falling down.
The plastic hook will give you an audible 'click' and hold it in place while the two housing screws are installed.
Ground Continuity Screw
Homeowners also need to verify that the ground continuity screw is in place on the bottom of the fan body. It will say "Secure screw tightly for ground continuity" on the sticker. This tiny screw connects the fan body to the adaptor assembly.
Should You Buy It?
What I Like
What I like most about the Panasonic WhisperFit is that it is an ECM variable speed motor. This means that it is ultra efficient and extremely quiet.
It also allows Panasonic to add a speed controller to the bath fan so you can choose the fan speed (50, 80, or 110-cfm). And since it is a variable speed motor, the WhisperFit will speed up or slow down to reach your desired CFM.
The retractable or hinged installation bracket included by Panasonic also makes installation significantly easier.
What I Don't Like
I'm not really sure why Panasonic doesn't include stress reliefs for the wiring so it can be secured to the junction box. It's a small thing but homeowners will have to go to the hardware store to buy one.
Stress reliefs prevent the wiring from rubbing on the metal edge of the junction box and potentially becoming an electrical hazard.
And beware if you don't like super quiet bathroom fans. Honestly, you may have some trouble noticing whether it is on or not — especially at the 50-cfm fan speed setting. If you want the fan to be louder or to get some of that white noise, just flip the speed controller switch to the highest fan speed at 110-cfm.
The Panasonic WhisperFit is an ideal choice for a standard bathroom fan that does NOT include a light, heater, speaker, or any other fancy add on.
Due to it's overall quality, I give the WhisperFit a 4.5 out of 5 star rating.