Wiring Timer to GFCI Outlet

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CommanderDave

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I have a 20A GFCI outlet that I want to wire a timer to that will control a ceiling exhaust fan. However the timer I have requires connection to a 3 wire (B,W,R-G) box, but the GFCI outlet is only powered by 2 wire (B,W-G); it also services three other outlets. So my question is can I wire the 3-wire timer to a GFCI outlet that is only powered by 2-wire? I've attached a diagram of the timer's wiring configuration.

1668793330379.png
 

wwhitney

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The timer is just acting like a switch: when the timer is on, then it connects its red to its black, and when the timer is off, its red is disconnected. Unlike a toggle switch, it also needs a neutral connection and constant power on its black wire so it can run the electronics inside.

If it's still not clear how to use the timer, how about a wiring diagram of your existing setup with the GFCI receptacle, the other receptacles, what wires are run between them, where the ceiling exhaust fan is and what wires you have or plan to run to it, and whether anything is connected to the load side terminals on the GFCI.

Cheers, Wayne
 

CommanderDave

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Attached rough drawing. Forgot to point out earlier that wire feed to the fan is 2-wire, but I could install 3-wire.
 

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wwhitney

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OK, so if you want the fan GFCI protected, then you take supply W and supply B from the load side terminals of the GFCI. If you don't want it GFCI protected, then you take supply W and supply B from the line side of the GFCI (the conductors shown at the bottom).

Then the timer is connected as: supply B to timer B; fan B to timer R; and supply W, timer W, and fan W all connected together.

As always, all EGCs (G) get connected together (and to the box if it is metal).

Cheers, Wayne
 

CommanderDave

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I tried to configure the timer to the load side but the light on the GFCI face would not come on, so I was obviously doing something wrong. I'm thinking to just bypass GFCI fan protection as you mentioned. If I understand correctly I connect timer B and W directly to B and W incoming power source BEFORE the GFCI, and jumper wire B and W incoming power to GFCI Line, leave Load side as is to service other outlets. And, wire nut/isolate the red timer wire, all G's connected. Correct?
 

wwhitney

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No, that's not correct. If my typed description isn't working for you, how about a diagram?

All EGCs are connected, so we can leave that out of diagrams. If you provide a schematic showing the fan (2 connections, B and W), the timer (3 connections, B, W, and R), the GFCI (4 connections, Line B and W, Load B and W), and the supply to the downstream receptacles (2 connections, B and W), then I'll draw lines on it to show how to hook everything up.

Cheers, Wayne
 

wwhitney

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Yes, that would work if the fan doesn't need GFCI protection.

But does it need GFCI protection? For example, if it's a bathroom exhaust fan mounted directly over a shower enclosure (a damp location), my understand is that the fan manufacturers all require GFCI protection for the fan in that application.

So if you need to GFCI protect the fan, the diagram below should work.

Cheers, Wayne
Fan With GFCI.jpg
 

CommanderDave

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Yes, that would work if the fan doesn't need GFCI protection.

But does it need GFCI protection? For example, if it's a bathroom exhaust fan mounted directly over a shower enclosure (a damp location), my understand is that the fan manufacturers all require GFCI protection for the fan in that application.

So if you need to GFCI protect the fan, the diagram below should work.

Cheers, Wayne
View attachment 88172
The fan is over my bar area not in a wet location so it has no requirement for GFCI. One thing that really screwed me up is when I was wiring everything I would not see the light come on the GFCI face; I had power but I was thinking it still wasn't wired right. So finally I looked up the GFCI outlet model and found that no light is normal status...every other GFCI outlet in the house has a green light for status. You know the old saying "I could have done it faster and cheaper but decided to do it myself."
 

Afjes

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One thing that really screwed me up is when I was wiring everything I would not see the light come on the GFCI face
CommanderDave:

Just so you are aware. Depending on the manufacturer of the GFCI the face light on the GFCI will function as per the instructions for that particular GFCI. Meaning, it is not always the case that a green light must be present for the GFCI to be wired correctly.

Unfortunately there is no standard for GFCI face lights. If green light is on the unit is wired correctly etc. You have to go according to the instructions for the GFCI that you are installing. Not all of them are the same. Keep this in mind.
 

CommanderDave

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Did you not see my entire post? "Just so you are aware" I clearly stated that I looked up instructions for that outlet and found a no light is normal status. Did you just parse one sentence from my post so you could lecture me on something I found out myself? Perhaps the next time you should read an entire post before responding, otherwise you may end up looking foolish. "Keep this in mind."
 

Afjes

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Did you not see my entire post? "Just so you are aware" I clearly stated that I looked up instructions for that outlet and found a no light is normal status. Did you just parse one sentence from my post so you could lecture me on something I found out myself? Perhaps the next time you should read an entire post before responding, otherwise you may end up looking foolish. "Keep this in mind."

I think this is kind of harsh as a reply to someone who was only trying to help you. I feel I was polite about how I said it.
I work with about 6 DIY electrical forums and give my free advice the best I can with the time I have. I don't always have the time to read every single word and let it all sink in. Sometimes I do miss something in the posts. I am 67 years old and a retired electrician. Sometimes my old eyes are not so good.

I read and answer many posts from several forums and do the best I can to provide my help.
 

DIYorBust

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This seems pretty straightforward, the timer has a red connector, that goes to the load, the fan. The white neutral goes to neutral. The black goes back to the GFI. You can put it on the line side or the load side of the gfi. I'd put it on the load side for GFI protection of the fan loop, why not, it's the same effort, and it could be great if a ground fault occurs on that loop. If that setup isn't working, something is wrong.
 
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