DIY Home Improvement Forum banner

Help How to Wire Bathroom "Fan Heater Light Night-light" unit, and questions

38762 Views 9 Replies 4 Participants Last post by  DCFear
Help How to Wire Bathroom "Fan Heater Light Night-light" unit, and questions


(First, please be patient with my questions. I have done some basic home wiring repair, and also I do this by the philosophy that with anything electrical, ask even the stupidist questions. Thanks!)

I purchased a Panasonic FV-11VHL2 WhisperWarm bathroom fan, I can't wait to have it hooked up. Now, I have it mounted in my cieling, and I have ran 12/2 wiring from the panel to my attic. My questions are about how to wire this unit up, performing this to code, etc.

To help you answer my questions, here is a link to the operating manual for the VHL2, which has a "Wiring Diagram" that unfortunatelly only goes as far as the unit itself.

First lets get this question out of the way. The manual says not to be used with solid state controls, ; may cause harmonic distortion and damage fan

Q: What is a solid state control? I have bought 2 electronic timers by Woods (see below), are these solid state, and will they shorten the life of my new expensive fan?

Q: Use on on a 20 ampere branch circuit - What does "branch circuit" mean? I have ran a single 12/2 from my panel for this project.

Q: Does 20 amp mean that I'll have to combine two 15 ampere spots on my panel with a 20ampere breaker?

CD500/CD600 Countdown Electronic Timers
CD500-30 minute settings
CD600-60 minute settings
• Simple push button activation
• Illuminated time indicator with 5-10-15-30 minute time ranges
• Silent operation
• Automatically turns off bathroom fans, lights, ventilators and more
• AC 120V/60Hz, 15A/1800W Resistive, 8.3A/1000W Tungsten,1/4 HP
Note: Wall plate not included. Resistive is the rating for appliances.

Q: For code, does the heater gang box need to be completely separate from the others? A contractor in HomeDepot mentioned this...

I really could use a ncie flow chart to describe exactly how to wire this unit, which I have not found from any forum yet!

1. a single 12/2 comes in

Q: Which box does the 12/2 first go into, the heater box or the triple box?

1. vanity light (has own circuit)
2. fan light
2a. fan night light
3. fan timer
4. heater timer (separate box)

Okay, sorry about the messy switches drawing, but my mind works in images, hence my desire for a wiring flow chart. Hopefully this post helps others as well...

Q: Does the 12/2 FIRST go into the heater gang box? And then get spliced with a Black wire going to the heater, and a black wire going to the triple gang box?

This all has to be on a dedicated circuit, so the vanity wiring remains completely separate on a different circuit, yet:

Q: is it against code to have 2 different circuit breaker wires in one gang box? (in the triple box) (the vanity circuit and the heater circuit)

See less See more
1 - 4 of 10 Posts
Branch circuit is simply a circuit from your panel to whatever it serves. You will hook your 12/2 to a 20 amp breaker and you will have a 20 amp branch circuit.

Typically, I use four switches on these units.

Fan, light, heater, night light.

You don't want the night light on 24/7

You can run your new circuit in with the existing light circuit but it would be more difficult for you and you would now have five switches. My limit is four because the materials are easier to find.

Typically I would run the new 12/2 down the wall, into a 4 gang plastic junction/switch box.

I would run two 12/3's from the switch box to the fan/light/heat/nl junction box. This in itself can be quite a challange because the JB's are often very small.

The wiring in the switch box is pretty simple. Bare grounds all together leaving pigtails for each of your switches.

Switch box:

White wire (neutral) from your incoming 12/2 ties to the white wires in the 12/3's going to the fan/light.

Black wire from your incoming 12/2 is your 120v power. Install 4 pigtails on it, one to power each switch.

The remaining wires(red/black, black/red)are your switch legs. They will carry current to the fan,light heater and night light. Hook these to the corrosponding wires in the fan/light JB. Mark them to keep them straight.


Black/red #1 = light/night light

Black/red # 2 = heater/fan


I didn't really understand the type of switch you are using but the wiring will be the same as if there were 4 individual switches. Maybe you have one, two gang switch that does all functions?. If so, change the existing lihjt sw box to whatever size you need and keep the existing light switch wiring completely separate, just how it is.
See less See more
Q: Will it violate code if I have the heater timer switch in the same gang box, as the fan, light, and night light?

Q: Is plastic better than metal for the gang box?'s non conductive and bigger.

Q: Again regarding code: Can I leave the 12/2 laying loose in my attic, or does it have to be fixed with those wire staples? (sorry, not sure what they're called)

Technically, no. If it is a true attic where you climb up and store stuff, staple the cable gently to keep it away from potential damage.

If your attic is like ours in AZ, it is strictly used for pipes wires ductwork and insulation and stapling is only a technical issue.

One more question, is it safe to put a sliding dimmer in the Bathroom for the vanity lights?


The VHL2 manual shows a picture of all 4 switches for this unit together in a double gang box ... so one would think Panasonic wouldn't suggest breaking code - right?

So it has two, double/stacked switches? Is one of them a timer like you described??

Whatever the case, you can put all the switches together in your 3 or 4 gang box.
See less See more
I do't want to say I told you so but....

Typically I would run the new 12/2 down the wall, into a 4 gang plastic junction/switch box.
You are going to struggle to end up with a safe installation. You think the sw box is small? Wait until you get to the fan/light jbox.

You don't have home depot in your area?
Code is a bit different in Canaduh.:yes:

And yes. The safety issuse come from cramming too much stuff into too litle space. The plastic box is larger and non conductive so it is a more logical choice.

If you plan correctly and don't leave more than 1/2 of sheath in the box, you can make the metal box work.

Enter all cables from the top of the box. MAke up you grounds and tuck them to the back. The groups should have just one bend. Too much wire is as bad as too little.

Do the neutrals next and tuck them back. Try and leave lots of room for the switches.
1 - 4 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.