Electrician installed GFCI on a kitchen split receptacle circuit using only one of the two hot wires

Question

I have a kitchen where I have a 15A receptacle on a split circuit (two hot wires and one neutral). Previously, it was set up with the brass connection cut with one hot wire for the top plug and the second hot wire on the bottom plug on the same receptacle.

I wanted to replace it with a GFCI receptacle for safety reasons (within 6' of a sink), and bring my kitchen up to modern code, but I know this is not possible with a split circuit, so I called an electrician to give me a solution and implement it.

The electrician simply put a wire nut on the red wire and screwed the black wire to the GFCI receptacle. This means that half of the circuit is just never used anymore, and the other half now serves the whole receptacle (which is now a GFCI receptacle).

I tried finding other people having done this on the web but couldn't find it, so I'm starting to worry that the electrician probably took a shortcut rather than do the job right.

Should I be concerned, or is this totally fine and up to code?

Edit: There's a bit more to my kitchen situation, but I only mentioned one receptacle (which is alone on its own circuit). Here is a diagram of the full kitchen situation. The receptacle I was talking about above is the one on the left. The receptacles on the right shared a circuit, but when he split them, the one receptacle (in the middle) is the only one that was not within 6' of a sink and the electrician insisted that we didn't need a GFCI there (even though it's a countertop receptacle and I had a GFCI receptacle handy).

PS: I didn't feel like making the ground in my little diagrams.

Answer 1

The basic problem is the mix of:

• Multi-Wire Branch Circuit (MWBC) to supply two 120V sets of receptacles while only using 3 wires instead of 4 (not counting ground). Which used to be a great way to supply two kitchen 120V circuits using a single MWBC (120V x 2/240V circuit).
• GFCI requirement for kitchens, which can be satisfied at the breaker (but not necessarily available, depending on the type of breakers you have) or at the receptacle (but receptacle GFCI does not allow for split receptacles as commonly used with MWBC).

The electrician did nothing wrong except that they may have caused a code violation with respect to the number of circuits in the kitchen. A kitchen is supposed to have at least 2 120V circuits feeding the receptacles. That can be satisfied with two totally separate circuits or with a properly installed MWBC. If this MWBC is the only circuit providing power to countertop receptacles in your kitchen then you now have a problem that needs to be fixed. On the other hand, if you have additional circuits powering countertop receptacles (if you turn off the MWBC, do you have any countertop receptacles that still work?) then you are perfectly fine as far as code is concerned.

If you want to fix this, either for convenience (more power!) or code (if there are no other countertop receptacle circuits) then you have two options:

• Breaker

If the MWBC is connected to a panel that (a) has double-GFCI breakers available for it and (b) it is either in a full double space (as opposed to 2 tandem breakers in the inner or outer pair of a quad) or there is a full double space available, then you can install a double GFCI breaker and install an ordinary split duplex receptacle (the old if you have it or a new one for $ 3) and you're done. Note that because this is an MWBC, you can't use two separate GFCI single breakers, even if handle-tied, as there is only one neutral in an MWBC and it would need to be split to the GFCI breakers, which just won't work.

If a double GFCI breaker is not an option, then you have to solve this at the kitchen end. There are a few ways to do this, including:

• Two GFCI receptacles side-by-side

Replace the single-gang box with a two-gang box. Install the existing GFCI receptacle and another GFCI receptacle. Pigtail the neutral to the line side neutral of both GFCI receptacles. Black goes to line side hot of one receptacle, red goes to line side hot of the other receptacle.

• Two separate GFCI receptacles

Electrically the same as side-by-side, but practically a bit different. Pigtail the neutral that is going to the existing GFCI receptacle. Run a 12/2 cable from this box to a new box where it is (a) helpful to have more receptacles and (b) not too hard to run a cable and install a box. Connect red from the MWBC to black of this new cable. Connect white to the MWBC neutral (same wire nut as has the pigtail to the existing GFCI receptacle). In the new box, install a GFCI receptacle.

Answer 2

The electrician simply put a wire nut on the red wire and screwed the black wire to the GFCI receptacle. This means that half of the circuit is just never used anymore, and the other half now serves the whole receptacle (which is now a GFCI receptacle).

That's perfectly fine and sounds correct to me.

You seem to be assuming that the MWBC (Multi-Wire Branch Circuit aka shared neutral) serves that receptacle only. That's not impossible, but it would be pretty unusual. Most likely the MWBC serves a chain of receptacles, and either they pigtail each one, or that one just happens to be last on the chain. Thus, the red wire is still serving those other receptacles.

Note that on MWBCs they are required to pigtail neutral.

Splitting circuits to a single receptacle is fairly pointless; they only ever did it because it didn't cost anything. When wiring a MWBC it makes just as much sense to alternate phase wires at each receptacle, e.g. receptacle 1 comes off L1, receptacle 2 comes off L2, receptacle 3 comes off L1, 4 comes off L2, etc. That method is compatible with GFCIs.

Answer 3

I think you need to get another electrician into this one. I'm not an electrician, but two circuits in a single receptacle box is almost certainly not to code. It's an invitation to electrocution if someone tests one receptacle and finds that it has been disabled, and assumes that the other receptacle is also not live.

As a matter of fact, I'd recommend you get another electrician to look closely at EVERYTHING your first electrician worked on. And by "recommend", I mean "Don't give me no back talk, don't say you'll think about it, just effing do it."