Using a bathroom fan and timer switch that both require "power first"?

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lhgrappler

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This is all new electrical, in a house that's stripped to the studs.
I am using the following vent/fan/light combo: (It requires power ran directly to it so that the fan can turn on on its own if the bulbs get too hot)
https://www.amazon.com/gp/product/B000VTSN0E
r/AskElectricians - Using bathroom fan and timer switch that both require power first??
(ALL three would be on separate switches though, Not Broan's 3 in 1)
And would like to use this fan switch: (It requires power to run the timer)
https://www.amazon.com/gp/product/B08GY5MT95
r/AskElectricians - Using bathroom fan and timer switch that both require power first??
Can these be used together? If so, are there and wiring diagrams you can point me to?
Thanks
 
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Fitter30

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Since the power wiring is common to one circuit breaker adding another switch to bypass fan timer just use the black power wire feeding both the three position and single pole fan wall switch the other side tie into bottom red wire on timer. Top red feeds thermostat for fan, bottom red will power timer switch and added fan switch.
 
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lhgrappler

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So, reading the Amazon reviews, tons of people have used timers with these just fine. The problem is I'm very visual and need a diagram.

Ideal set up: Heat lamp and fan on timers in 2 gang box, Light would be with vanity light in different 2 gang box.

Can anyone help with a diagram?
 

wwhitney

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Can these be used together?
Yes. In the wiring diagram you posted, just connect the brown output of your fan timer to the red wire in the righthand cable (which I'll call the fan cable) from the switch box to the fan.

Since you have 3 separate switches, your switch box wiring is a bit more complicated than the Broan 3 in 1 wiring in the diagram. I'll assume simple switches for the heat and the light. Then in the switch box you'd have:

All grounds tied together
Incoming Black (Hot) connects to 4 other wires--jumpers to the 2 switches, pigtail from fan timer, plus the black in the fan cable
Incoming White (Neutral) connects to 3 other wires--pigtail from the fan timer, plus the whites in the fan cable and the heat/light cable
Light switch connects to Incoming Black and to Black in the heat/light cable
Heat switch connects to Incoming Black and to Red in the heat/light cable
Fan timer connects to Incoming Black, Incoming White, and the brown wire to the Red in the heat/light cable

Cheers, Wayne

P.S. Note that each cable having its own neutral (white) is a bit redundant, although fine as long as you don't mix up the white wires in the fan box. A single 5 conductor (plus ground) cable would suffice instead of the two 3 conductor cables shown. If using NM cable (Romex), you can make the equivalent of a 5 conductor cable by simply using a 2 conductor cable plus a 3 conductor cable and routing them together (in contact everywhere, using the same holes in boxes). Then you'd relabel say the 2-conductor white to red at each end, and use the other white for both white wires at the fan. If this comment is confusing, ignore it.
 

Fitter30

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Or do u want one like the factory?
17307412505915812765712865688006.jpg
 
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wwhitney

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Since the power wiring is common to one circuit breaker adding another switch to bypass fan timer just use the black power wire feeding both the three position and single pole fan wall switch the other side tie into bottom red wire on timer. Top red feeds thermostat for fan, bottom red will power timer switch and added fan switch.
I don't understand what you are attempting to accomplish here. Per the diagram provided, the fan/heat/light unit has 6 connections (plus ground): fan constant hot (which presumably goes to an internal thermostat to run the fan if the unit overheats), fan switched hot (for when the user wants fan), fan neutral, heat switched hot, light switched hot, and heat/light neutral. Your schematic in the previous post doesn't shown any such 6 connection block, and I don't think the OP wants to get into rewiring the internals of the unit.

I understand the OP to want to be able to control the fan using the timer shown (with neutral, hot, and switched hot pigtails) in lieu of a normal on/off switch. And to control the heat and the light each with a normal on/off switch.

Cheers, Wayne
 

lhgrappler

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I was able to figure it out thanks.
In the fixture:
Red = Heat lamp
Black = Light
Blue = vent
Yellow = safety vent, always powered
White = Neutral
Gray/White = ??? More neutrals?

I will be bringing in three wires -
12/2 from light switch (separate gang box) - black to black
12/3 from fan timer - black to blue, red to yellow (not used with switch)
12/2 from heat lamp switch - black to red

I'm not sure about all the neutrals at the fixture though. The diagram shows two different neutral bundles and one of them has an extra piece for no apparent reason?
1730757638102-png.813889
 

wwhitney

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I will be bringing in three wires -
12/2 from light switch (separate gang box) - black to black
12/3 from fan timer - black to blue, red to yellow (not used with switch)
12/2 from heat lamp switch - black to red

I'm not sure about all the neutrals at the fixture though. The diagram shows two different neutral bundles and one of them has an extra piece for no apparent reason?
You're supposed to use (2) 12/3s instead of the the above. One 12/3 has the neutral for the fan, along with switched fan and constant power, and the other 12/3 has the neutral for the light and heat, along with switched light switched heat. The fixture correspondingly has two different neutral connections, one for each cable. Don't mix them up, although in practice if you follow the requirements of the postscript in post #4, it's not a problem.

Cheers, Wayne
 

lhgrappler

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The fan and heat timer switches are in a different location than the light switch. Not sure how that will work.
 

wwhitney

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The fan and heat timer switches are in a different location than the light switch. Not sure how that will work.
In that case I would definitely counsel against your 12/2, 12/3, 12/2 plan, as it can't comply with the routing requirements in the postscript to post #4. And it's important that you not mix up the neutrals at the fixture.

But you can run a 12/3 from the light switch location to the heat timer location, carrying switched light power, constant power, and the associated neutral. And then run a 12/3 from the heat timer location to the fixture, carrying switched light power, switched heat power, and the associated neutral. Or vice versa, from the heat timer location to the light switch location to the fixture, if that's easier.

Cheers, Wayne
 
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