Tapping into existing circuit

sjnick

I'm installing a fan in our bathroom that never had a fan. There's a 20-amp 12/2 wire that runs from the panel to the jet controls of our bathtub.

I'd like to somehow tap into this circuit to power the fan and a new switch for the fan. If I cut the Romex that runs through the attic before it travels into the wall to the bathtub, is there some sort of T connector I can use to add another 12/2 wire directly to the fan?

Thanks.

k_buz

Whirlpool tubs generally require their own 15 or 20A circuit. You will need to find something else to tap off of. It can be any lighting circuit.

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frenchelectrican

The whrilpool tub system genrally are on delicated circuit so you will have to find something else like your light switch in your bathroom is a good place to tie into it.

So one of the most common way is hook the fan to one of the ceiling luminaire so that way when you turn the ceiling luminaire on the fan do come on at the same time.

Or add a extra gang box ( it can be 2 or 3 depending what ya got there ) and wired from there.

Merci,
Marc

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The answer will be based on NEC ( National Electrical code ) or CEC ( Cananda Electrical code ) or ECF ( Electrique Code France )

joecaption

All connections will need to be made in a juntion box that accessable and has a cover.
So no there no such thing as a "T" fitting.
When you cut a wire in the middle of a run there's almost never enough wire to make a proper connection.

Toller

The one time I tried this I was able to improve how the wire ran well enough to make it work. But I got lucky.

Could you put both ends into a box and attach some pigtails to one side to make it all longer. It would be really ugly, but would it be allowed?

A few years back I saw a device that allowed you to connect wires outside a box. Never tried it and haven't seen it since, but it looked like it would work.

JKeefe

That's the crux of your problem right there. You need a circuit different from your bathtub, but if you find one and you've got accessible wiring (say in an attic over your bathroom), you can cut the wire in two different locations and thus create enough length to feed into two new electrical boxes. You will need to connect those two boxes together using whatever sort of wiring is there now (returning your wiring to its former state), and you can run wire to your fan from one of the boxes as well. That's how you create your "tee" - it's not really a tee.

If you don't have accessible wiring the job will be a lot more tricky.

fa_f3_20

What you do is put in two boxes, about a foot apart. You cut the line you want to tap into and run one end to one box, and the other end to the other box. Then you put in a short piece of romex (or whatever method is approved in your area) between the boxes. It's kind of a hack, but sometimes there is no better way.

sjnick

The rest of the wiring for the bathroom is old knob and tube. I don't want to mess with it. Although it sounds like the tub requires its own circuit, the fan only requires .1 amps to run, so it'd be a negligible load. Plus we never use the jets in the tub anyways.

All of the houses ceiling fixtures are on one circuit. I'll see about tapping into that.

Jim Port

Ungrounded knob and tube should not be extended.

It does not matter that you are only talking about adding 1 amp of load to the tub circuit. The tub requires an individual branch circuit that is not shared.

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Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.

sjnick

Well, it sounds like I'll have to run a new circuit for the fan. That's a big expense for a tiny electrical load, but I'd rather be safe. Thanks for the advice.