Adding GFI to old two conductor house

[oilslick]

I am looking to add gfi protection to a house that has two wire throughout[built in 60]. I plan to install a GFI outlet inline coming off breaker box on the 8 circuits leaving the breaker box, I am just trying to figure the best/easiest way to do it without my being a DIY electrician being a putoff to buyers. I want it safe but not able to spend an arm and a leg, function over form! any tips? I priced GFI breakers no way!!

 

[Berserker]

I am not sure the code on it. But you can replace the outlet with a GFI. It will be better then having no ground.

 

[cowboyjosh]

yeah you can add GFCI protection to 2 wire conductor circuits; and downstream outlets. To keep it as close to code as possible, just be sure to put the stupid little stickers that come with the GFCI outlet that state "no equipment ground" to all downstream outlets and the GFCI outlet itself.

 

[Berserker]

Thats what I would do, unless I had a major remodel planned. How much are GFI breakers? Years ago when I did consulting, my boss had me spec them for a bar area. A GFI is about $10 a pop.

I guess a good thing, about GFI breakers, is someone will know to check the panel, if the power is out.

 

[fefarms]

If you can trace the circuits, and replace the first receptacle in each circuit with a GFI breaker, you will have GFI protection for that receptacle and all the downstream ones. You can then replace two-prong downstream receptacles with 3-prong receptacles labeled "GFCI protected, no equipment ground". Tracing the circuits from the breaker box to the first receptacle can be quite challenging in an old house.

GFCI breakers aren't that expensive, at least for common brands like Square D or Siemens. Figure $20 to $40 per breaker depending on brand and where you buy it. Replacing the breakers in the panel is relatively fool-proof and saves tracing the circuits.

I hope you aren't thinking of splicing in extra GFCI receptacles right at the panel, just to save money on the breakers. The extra boxes, splices, wire, and effort will. cost more than the breakers, and the end result will look like amateur hour.

 

[VHF]

Why do you want GFCI protection for so many circuits? Do all 8 circuits serve wet areas?

 

[Berserker]

I think he wants it because he has no ground. The GFIs would give you some protection.

 

[mrb]

unless i had someone come in, disconnect everything, and megger the existing wiring I would be weary of installing GFCI breakers in the panel only to discover they trip every time it gets humid or whatever. In an old house with no ground I would just spend the money to replace each receptacle with a GFCI. How many receptacles does the house have, 20?

 

[Zeke]

unless i had someone come in, disconnect everything, and megger the existing wiring I would be weary of installing GFCI breakers in the panel only to discover they trip every time it gets humid or whatever. In an old house with no ground I would just spend the money to replace each receptacle with a GFCI. How many receptacles does the house have, 20?

No need. As mentioned, one receptacle at the first box in a string and they are all protected. The fact that there is no ground wire present does not affect the effectiveness of a GFCI. The third wire which is tied to the ground buss is a back up for the neutral and in many cases grounds any metal work on a fixture or appliance when the line circuit is isolated. This would be the case with a light fixture and all switches, metal boxes and outlets. If the metal becomes energized, the GFCI would trip because of current running to some other ground other than the one that the device is wired to.

This would be in the case of someone coming in contact with current passing through their body. Actually, the GFCI should open the circuit if it's only a 2 wire circuit and current is going through the metal chassis and to ground other than what it is wired to. In that case where the chassis is not grounded, it's pretty certain that if energized, it will trip if you and your body provide a path to ground.

People may disagree, but a GFCI device is just as effective as a protection against electrocution on 2 wire circuit as 3 wire circuits.

I know that is redundant, but I'd rather say too much than too little. Do not fail to install GFCI's because you think they don't protect a 2 wire circuit. They do.

 

[Berserker]

I think a GFI is looking at current, if some if it is not accountable, it trips. I believe its just differential protection. So a ground would nothing to do with it.

Find what you think is the first outlet from the panel. disconnect and break the wire nuts, and then see what other ones are dead.

I would turn off your TV and computer when doing this, just in case you get the wrong circuit. Granted its like flipping the breaker off, but still not a bad idea.

 

[Berserker]

unless i had someone come in, disconnect everything, and megger the existing wiring I would be weary of installing GFCI breakers in the panel only to discover they trip every time it gets humid or whatever. In an old house with no ground I would just spend the money to replace each receptacle with a GFCI. How many receptacles does the house have, 20?

I never thought about this. Never though about meggering my house either.

I am not sure if this is good thinking or overkill.

But if the problem existed, you would still trip wether the outlet or the breaker. You just wouldn't trip for the section for the panel to the first outlet.

 

[oilslick]

I added them to outside the breaker box and yes it does look ******, lesson learned, main thing is that it now has GFI on all 110 circuits.

 

[oilslick]

Oh what does megging mean?

 

[Berserker]

Its a way to test the insulation. Megger is actually a brand name, but its what everyone uses.

 

[mrb]

No need.......(too long so i snipped it)

i think you missed what I was getting at. Old wiring, passing through who knows what, is going to be a bit 'leaky' and with gfci protection between 4 and 6ma you dont really have alot of room to play with. This plus the cumulative leakage of everything plugged into the circuit (surge protectors, computer power supplies, etc) and you may end up with the gfi tripping when it shouldnt have.

By installing individual gfci receptacles instead of a breaker or one gfci receptacle supplying multiple downstream receptacles you eliminate tripping caused by building wiring in poor condition and cumulative leakage from various loads.

 

[Zeke]

i think you missed what I was getting at. Old wiring, passing through who knows what, is going to be a bit 'leaky' and with gfci protection between 4 and 6ma you dont really have alot of room to play with. This plus the cumulative leakage of everything plugged into the circuit (surge protectors, computer power supplies, etc) and you may end up with the gfi tripping when it shouldnt have.

By installing individual gfci receptacles instead of a breaker or one gfci receptacle supplying multiple downstream receptacles you eliminate tripping caused by building wiring in poor condition and cumulative leakage from various loads.

So, you're saying that GFCI's work like a filter and the one placed closest to the panel won't see differential because of others installed downstream in the "leaky" branch circuit? I don't think so.

But, if you can show me, I'll become a believer.

 

[fefarms]

No, he isn't saying that. He suggests installing the GFCI so that it only protects its own receptacles, and leaving the "downstream" screws on the GFCI unused. This way it will only read the current imbalance at the receptacles, and will not care about leakage in the wiring, or in any other receptacles on the branch circuit.

 

[Zeke]

OK, my bad for not realizing that pigtailing each recp would protect each outlet individually. Actually, I had a situation where someone had 2 GFCI's in line with each other on the same circuit and they were wired line and load as one would tend to do if not thinking and just reading the instructions. I had a hard time convincing the homeowner that taking the 2nd one out meant no change since her son had done the initial installation of these.

Now, after reading your post, I could have pigtailed the 1st one and let the 2nd one protect everything downstream.

Thanks for the clarification.

 

[Aceman]

I know what MRB's talking about, there's a rule of thumb somewhere for the maximum amount of receps on a GFI breaker to avoid nuisance trips. I want to say it's around 7 or so, but I don't really remember.

With that said, I've added(and the other guys in my shop too) GFCI breakers to houses that were being brought up to code from a home inspection, etc with no issues. At least I've never been called back...?

As a matter of fact I just changed a GFCI breaker in a house today because the old one had failed, but it was older than dirt. Just like most older houses, it fed some miscellaneous lights and receps and hasn't had any nuisance trips as far as I know.

I've also added GFCI receps at the beginning of circuits also. But my time is fairly expensive so if you're paying an electrician to do it I would think you may come out a bit cheaper to just have him change the breakers in the panel rather than trying to chase down the first receptacle on every circuit just to throw a GFCI in. If you're going DIY it might be worth the time to find them.

Personally, if I had to do it in my own house, I'd absolutely use breakers. I don't want to have to go looking for the tripped GFCI recep nor do I want to use GFCI receps in every box.

 

[Zeke]

Personally, if I had to do it in my own house, I'd absolutely use breakers. I don't want to have to go looking for the tripped GFCI recep nor do I want to use GFCI receps in every box.

Man, I'm with that. In my example, the kid's bath was ahead of the master bath and they were tripping the GFCI all the time (I don't know why, really). So, the parents had to go into the kid's bath to reset the GFCI.

If I had my way, I would have run a dedicated circuit to one or the other to get them off a common circuit. (I did end up installing another outlet on the other side of the master bath off another circuit and installed a GFCI recp in that location. Problem solved in part.)

BTW, this was a newer home with 2 and 3 wire conductors with grounds throughout. So, it really doesn't pertain to this thread except how to use multiple GFCI's on the same circuit.