GFCI Receptacle Installation

[BaileyNo5]

We had a home inspection recently, and found out that several of our outlets near sinks were not GFCI protected.  So I'm busy installing a few GFCI outlets, and I know how to handle a standard installation, making sure LINE and LOAD feeds connect to the proper terminals.  But I haven't seen this kind of wiring before, so I thought I better ask someone before I blew something up (I did blow trip the breaker twice trying different things).  This is the third one I'm working on, and so far all three have had different wiring configurations, leaving me scratching my head every time.

In the picture below, you can see the usual hot wire (black), neutral (white) and ground (bare).  In addition, there is a red wire, which is also hot.  Have no idea what the red wire is connected to. 

I tried connecting the black wire to the LINE and the red wire to the LOAD, and that definitely was not a good idea, as I blew the breaker (I temporarily forgot this was GFCI and wired it like a normal outlet).  This quickly reminded me I was dealing with GFCI.

I have one idea left, and that is to connect both the black and red wires to the LINE terminal on the GFCI outlet.  Thought I would wait for some sage advice before doing that.  What say you, electrical nerds?

[Willyou]

That is a 240 v circuit. With a volt meter you will get 240 v between the red and black and 120 across the red and white and 120 v across the black and white. They are currently connected to a standard duplex outlet with the brass tabs split so that each outlet is 120 v but on separate circuits. I assume you are trying to wire in the GFCI the same way to replace the existing duplex outlet. I don't know if you can (or should) do it or not.

[Roly]

That is a 240 v circuit. With a volt meter you will get 240 v between the red and black and 120 across the red and white and 120 v across the black and white. They are currently connected to a standard duplex outlet with the brass tabs split so that each outlet is 120 v but on separate circuits. I assume you are trying to wire in the GFCI the same way to replace the existing duplex outlet. I don't know if you can (or should) do it or not.

This
On your picture the brass tab is missing so it was wired (split wired) as two circuits.   Can't do that on a gfci.  Suggest caping off the red and just using the black and white normally. Unless at one time two larger appliances were used at the same time at that location.  Roly

[Don_M]

Black and Red wires are usually hot (can’t think of a circumstance where they would not be),

White (and sometimes Grey) wires are grounded conductors (i.e.,  neutrals)

Are there any other wires in the box that are NOT connected to the receptacle ((i.e., a “pass-thru” circuit”)? The Red wire indicates to me that you have a 3 conductor cable running into that particular JB. One black (hot) wire , 1 Red (hot) wire and one White (Neutral) wire. If not, then several things come to mind:

1.      It may be part of a 240 circuit. You can verify be checking voltage across the two hot (black and red) wires. You should get 240 vac across the Black and Red wires; 120 vac across the black/red and the neutral You may also be able to trace this back to the sub-panel and see if this circuit is a on a 240 breaker.

2.      Sometimes (to save time/money) electricians will run a 3-conductor cable to a single box where two appliances might be connected (say a dishwasher and a disposal). Again, the bonding tab would need to be removed and note the single neutral is carrying the load for both appliances (usually not an issue). But again this strikes me as a bit odd given they are GFCI receptacles. Not even sure this would work with w GFCI as they may be enough imbalance between the neutral and one of the other loads so as to cause the GFCI to “trip”

3.      It is part of a switched leg. That is, each receptacle is electrically isolated from the other and one is a live while the other is live only when switched on. (FWIW – I doubt this is the case for a GFCI circuit)

4.      It is just an extra wire (was it connected to anything before?)



"I have one idea left, and that is to connect both the black and red wires to the LINE terminal on the GFCI outlet.  Thought I would wait for some sage advice before doing that.  What say you, electrical nerds?"

I don't think this iis a good idea - and not even sure it would work with a GFCI circuit.

[Cabinet Monkey]

I’d suggest you go get 2 GFCI breakers and install them in your panel in place of the two reg. breakers that feed that receptacle now. 

Yes, it’s more expensive. Yes, you need to shut off power to the panel before working on it (or you should anyway) but it’s the only real way to keep the functionality you have now.   

[BaileyNo5]

Roly, Don, Willyou, CabinetMonkey, thank you for helping out.  CabinetMonkey, thanks for a possible solution that I hope I can implement.

Here's a little more detail.  This is an outlet on the kitchen island, right by the sink, which has a garbage disposal.  The dishwasher is directly below this outlet.  The panel has 2 15 amp breakers that are tied together (I haven't pulled the panel off yet, but I'm assuming this is right).  I shut the breakers off - the dishwasher doesn't work, but the garbage disposal does, so it looks like the dishwasher is the only thing tied in to it.  Right now I'm shaking my head about the moron electricians that wired this house.  5 outlets by sinks had no GFCI protection. We asked about this when we moved in, because the outlets obviously weren't GFCI, and were told the breakers were GFCI.  Over the years as I had to do minor electrical work, I found just about every breaker in the panel was mis-labelled, including the GFCI breakers.  And now I find this.....I'm just shaking my head.

But, if I can slide breaker or breakers in that are GFCI, I will happily pay the money to get it done.  How should I handle the two breakers that have the switches tied together?  Is that going to be a problem to get a GFCI breaker that will work?

[Roly]

Roly, Don, Willyou, CabinetMonkey, thank you for helping out.  CabinetMonkey, thanks for a possible solution that I hope I can implement.

Here's a little more detail.  This is an outlet on the kitchen island, right by the sink, which has a garbage disposal.  The dishwasher is directly below this outlet.  The panel has 2 15 amp breakers that are tied together (I haven't pulled the panel off yet, but I'm assuming this is right).  I shut the breakers off - the dishwasher doesn't work, but the garbage disposal does, so it looks like the dishwasher is the only thing tied in to it.  Right now I'm shaking my head about the moron electricians that wired this house.  5 outlets by sinks had no GFCI protection. We asked about this when we moved in, because the outlets obviously weren't GFCI, and were told the breakers were GFCI.  Over the years as I had to do minor electrical work, I found just about every breaker in the panel was mis-labelled, including the GFCI breakers.  And now I find this.....I'm just shaking my head.

But, if I can slide breaker or breakers in that are GFCI, I will happily pay the money to get it done.  How should I handle the two breakers that have the switches tied together?  Is that going to be a problem to get a GFCI breaker that will work?

A gfci works by comparing the current in the hot leg and the current in the neutral.  Either too much or too little current in either will cause it to trip. Try capping off the red wire by the receptacle and installing the gfci outlet, turn all back on and see if everything works.   The dishwasher is getting a neutral from somewhere, probably a junction box.   A gfci at the panel will see neutral current if either the outlet  or dishwasher is used and trip the breaker .     Dont connect 240v across a gfci outlet unless you want to see smoke and buy a new gfci. 
Is the dishwasher plugged in, if so you could change that to a gfci outlet along with changing the countertop one.  Roly

[Don_M]

Question: the two breakers tied together – the wires going to each of the breakers; is one of the wires black and the other red? If so, then tying the breakers makes sense because it sounds like a 3 wire cable using a common neutral and tying the breakers together allows them trip if either circuit overloads/shorts.

Is the dishwasher plugged into this receptacle?

Then perhaps the red (or black) ran the dishwasher and the other was for the GFCI protected appliances. But removing/breaking the bonding tab between each outlet will likely give you trouble with a GFCI receptacle due to a shared neutral and possible current imbalance (I doubt a GFCI will even function property).

You could try a double pole GFCI breaker (not cheap) and then use a regular duplex receptacle in the box. Black wire to one of the outlets; red to the other. Remove the bonding tab between the outlets and then one of the outlets would be for small appliances and the other the dishwasher. Both will be GFCI protected (although typically not required for the dishwasher). This is not a whole lot different from just ignoring the red wire (dishwasher circuit) all together, but it looks closer to a code installation -  i.e., dedicated circuit for the dishwasher and at least one dedicated small appliance kitchen circuit.

[brianwelch]

Not sure how/whether this would work for you, but...Could you use a add'l outlet on the other side of the wall where the outlet is being upgraded to GFCI? Rather than capping the red, you might be able to feed an additional outlet...

[BaileyNo5]

Not sure how/whether this would work for you, but...Could you use a add'l outlet on the other side of the wall where the outlet is being upgraded to GFCI? Rather than capping the red, you might be able to feed an additional outlet...

No, that's not really an option I would consider at this point.