Panasonic Bathroom Exhaust Fans – A Definitive Guide
R.E. Williams Contractor Inc. © 2007 All Rights Reserved


Tightly constructed homes and improper ventilation is a sure recipe for trouble.  Bathrooms can be of a significant problem, as this is where high moisture and humidity levels are present. However, if you take the simple precaution of installing a quality exhaust fan in your bath, you can ensure that your bathroom is not damaged by heat, excess moisture, and steam. And since we are talking of a quality exhaust fan, there is none better than the Panasonic line of bathroom exhaust fans. 


Benefits Of Panasonic Bathroom Exhaust Fans



Sizing Panasonic Bathroom Exhaust Fans


The simplest way to calculate what size fan you require is:

Step 1
: Calculate the cubic feet of your bathroom (length x width x height)
Step 2: Divide by 60 (the number of minutes in an hour)
Step 3: Multiply the result by 8 (the number of recommended air changes per hour)


We designed a bathroom fan calculator to help with this task.


Another method recommended to sizing a bathroom duct fan is below.


For bathrooms that are less than 100 sq. ft. in size, you can simply calculate the area (length by width) of the bathroom and that will be the fan size (in CFM) that you need. For example, if the length and width of a bathroom are 8 feet and 6 feet respectively, the area is 48 sq. ft. Thus, you need a bathroom exhaust fan that has a minimum CFM rating of about 48.  


For bathrooms that are bigger than 100 sq. ft. in size, the size of the exhaust fan will be reached by adding the different fixtures in the bathroom. For fixtures such as toilet, shower, and bathtub add 50 CFM for each fixture, whereas whirlpool and jetted tubs will be an additional 100 CFM.


Our real world experience in the field of residential ventilation fans, also tell us that a little more cubic feet per minute of airflow in a fan is always better than a undersized fan that isn’t powerful enough to ventilate a bathroom.   


What Panasonic Fan Is Right For Me?


Here we will explain the basic differences that set all the different models apart:


FV-VK –Series of Panasonic fans, the WhisperGreen line.  These are Panasonic’s newest fans.  Not only are they quiet and efficient, but have some great features not found in the other models.  Specifically, the FV08-VKM1 has an integrated motion sensor in the grill of the unit.  When the fan detects motion, it turns on.  It also has an integrated timer in the fan housing that you can set to adjust how long after motion is not detected the fan will run.  This makes it very simple for you to use, no need to turn on and off switches, it’s all automatic once set up.  This is a great fan for homes with kids, who always seem to forget to turn the bathroom fan off.  It also insures that the fan will run for at least 20 minutes, after you are done showering or bathing, something that is very important to evacuate moisture from the home.   But this fan does more, it has what is called SmartFlow™ Optimum CFM Technology. This unique "electronic-brain" lets the fan do what was once thought to be impossible, perform at a constant CFM regardless of elbows and other factors that might hinder performance.  Moreover, the fan can be set for constant duty operation.  Meaning it will continue to ventilate at very low levels, and when turned on, either via switch or motion sensor, will kick up to the fan’s highest cfm level.  The FV08-VKS1 performs exactly like the FV-08VKM1, except it does not have a motion sensor.  In the past, if you wanted the fan to operate at a constant duty, or variable speed, you would have to purchase a separate controller; this is no longer the case.


FV-VQ3 – These are Panasonic’s flagship ventilation fans, known for their performance, efficiency and quiet operation levels.  The FV-VQ3/FV-VQ4 series are some of the quietest fans Panasonic manufactures.  They are known as the WhisperCeiling line.  These fans are available in size from 50 – 380 cfm.  These fans are what we would recommend for your home.  However, this series of fans may not work when attempting to retro fit them into an existing sub-floor area of a multiple story home.  Always measure the area of where you plan on installing the fan for proper clearances.


FV-VQL4 – These are also the flagship series of Panasonic fans and are exactly like the FV-VQ3 series of fans, except these fans have lights built into them.  The “L” in the model number denotes a unit with a light in it.  They are known as the WhisperLite series.  Panasonic had a lighting division that was phased out.  The bulb and ballast technology from that division was carried over into the light fixture of this fan.  From bulb to ballast, everything about it is top notch. The lights in these units were converted over to a fluorescent type bulb several years ago.  The light uses an “instant on” ballast and bulb, when you turn the light on, it turns on, there is no irritating flicker and buzz that can be seen in lesser quality fluorescent fixtures.  Why fluorescent bulbs?  It’s due to energy efficiency.  The bulbs use less energy, and have a brighter light output than an incandescent bulb.  The Sate of California implemented a law, called Title 24, it requires all newly constructed homes to meet certain efficiency levels across the entire realm of the home.  The fluorescent lights in these fans meet those requirements.


FV-VF2 – Is known as the WhisperFit series of fans.  These fans were designed to be installed in tight sub-floor areas of a home, the height of the unit is 5 5/8”, a very low profile.  With these fans, noise levels are slightly higher vs. the FV-VQ3/FV-VQ4 and FV-VQL4 series of fans.


FV-VFL2 – This is known as the WhisperFit Lite series of fans.  These ventilation fans share the same characteristic as the FV-VF2 series of fans, but have the added feature of a light. 


FV-11VH1/FV11-VHL1 – The Panasonic Whisperwarm series of fans.  These are Panasonic’s exhaust fan/heater models.  Built into each unit is a separate exhaust fan and a heating element.  The FV-11VH1 fan, is an exhaust fan/Heater.  The FV-11VHL1, features an exhaust fan, heater, light and nightlight combination. 

The FV-11VH1, would require a switch to turn the fan on/off and one to turn the heating element on/off.  While the FV-11VHl1 would use a switch to operate the on/off exhaust, on/off heat, on/off light and on/off night light of the fan.  A switch we would recommend for the FV-11VH1 can be found here.  As well, a switch for the FV-11VHL1 can be found here.


The dimensions of these FV-11VH ventilation fans are quite large, it is recommended that you measure the area where you plan to install the fan, to insure it will fit.


Note: The Panasonic fan heater units should NEVER be installed in a shower enclosure or directly over a tub.


FV08-WQ1 – The WhisperWall ventilation fan. This fan was designed for through the wall ventilation applications.  No ducting is required, as the fan’s housing penetrates directly to the outside. 


Panasonic also makes a series of inline fans called the WhisperLine.  These fans are remotely mounted fans.  An exhaust grill is placed on the ceiling and then duct is connected to the main unit.  These inline fans are available in sizes from 120 – 440 cfm.  A number of fan accessories are also available.

Panasonic also makes a fire rated damper, which can be used on conjunction with most of their ventilation fans.  Local fire codes may require a ventilation fan installed in a fire rated floor/ceiling or a roof/ceiling assembly to be equipped with a specially tested and classified radiation damper, in case of a fire.  The radiation damper closes to prevent the spread of fire and heat.  Panasonic radiation dampers are designed to protect ceiling penetrations in 1.2 or 3 hour fire-rated floor/ceiling and roof ceiling designs. 

Installing Panasonic Bathroom Exhaust Fans


While it is important to follow the manufacturer’s guidelines for specific models, here are some general installation tips that will help you to install your exhaust fan in the best location possible so as to achieve maximum ventilation.



Tools and supplies needed for installation of bathroom exhaust fans are:



Here are the steps that you need to follow while installing your Panasonic bathroom exhaust fan:


Find a location where you want to install the fan.


1. Making the opening: in either the wall or the ceiling, depending on the type of exhaust fan and where you want to install it.


2. Installing the duct kit: either directly on the joist or by using the special metal hanger if the joist is far from the opening.


3. Ducting to the outside of your home: Make sure to choose the shortest route possible and with the least number of elbows.


4. Wiring the exhaust fan: Wiring will depend on whether it is a simple exhaust fan or a combination light/fan unit and whether or not you choose to have an automatic timer.  If you are unfamiliar with wiring, or local codes, it is always suggested that you contact a licensed professional to do the job for you.


We hope this has clarified and explained in detail, everything you wanted to know about Panasonic exhaust fans.  If you still have further questions, free expert advice can be found by calling us toll free at 888-845-6597, we are here to serve you M-F from 7 am – 5 pm PST.


This guide is provided as a service from R.E. Williams Cont. Inc.  Please be aware, that building codes and local regulations differ from region to region, they also can change.; therefore, R.E. Williams’ Cont. Inc. assumes no liability for omissions, errors or the outcome of any home improvement project.  You should always exercise reasonable caution, follow your current codes and regulations that may apply, and if in doubt on any procedure consult with a licensed professional.


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