Home>Discussions>ELECTRICAL & LIGHTING>Install Arc-Fault Circuit Interrupters to older wiring??
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rickpantel
Install Arc-Fault Circuit Interrupters to older wiring??

I'm new to this forum and have a question regarding Arc Fault Circuit Interrupters (AFCI's).

We recently moved into an older house (circa 1950). The governing electrical code is BC, Canada. The wiring is 100 A service, with a knife switch main breaker and cartridge-type main fuses. A 40A sub-panel has been added for newer wiring, but most of the house is still on two original circuits...bedrooms, bathrooms, lighting and outlets all on the same circuits. There is lots of room in the sub-panel for new circuits. There is no knob and tube wiring anywhere. The house has plaster walls, and running new wiring would be very difficult in some sections of the house. The older circuits seem to be 14ga wire (:confused:Romex wiring with the black outer sheath) on standard 15A breakers. The older circuits are not grounded. We are planning a major gut and reno in a few years, and will re-do the wiring at that time, so I don't want to get into a major rewire job now until we do the rest of the upgrade. I'm planning on doing an electrical map and splitting up the old circuits in cases where we have access and can run new wire easily.

Questions for the forum:

1- Is it worthwhile to change the existing breakers on the old ungrounded circuits to newer AFCI breakers? I'm worried about the condition of the old wiring in places that can't be inspected, and I wonder if a greater degree of protection can be achieved with AFCI breakers on an old circuit. The circuit won't be just plugs, but lighting, dimmers, etc. Is this a good idea?

2- Any other suggestions for easy safety upgrades to an old house, short of doing a major electrical reno??

Thanks in advance to the members of the forum for considering our questions.

Re: Install Arc-Fault Circuit Interrupters to older wiring??
rickpantel wrote:

I'm new to this forum and have a question regarding Arc Fault Circuit Interrupters (AFCI's).

We recently moved into an older house (circa 1950). The governing electrical code is BC, Canada. The wiring is 100 A service, with a knife switch main breaker and cartridge-type main fuses. A 40A sub-panel has been added for newer wiring, but most of the house is still on two original circuits...bedrooms, bathrooms, lighting and outlets all on the same circuits. There is lots of room in the sub-panel for new circuits. There is no knob and tube wiring anywhere. The house has plaster walls, and running new wiring would be very difficult in some sections of the house. The older circuits seem to be 14ga wire (:confused:Romex wiring with the black outer sheath) on standard 15A breakers. The older circuits are not grounded. We are planning a major gut and reno in a few years, and will re-do the wiring at that time, so I don't want to get into a major rewire job now until we do the rest of the upgrade. I'm planning on doing an electrical map and splitting up the old circuits in cases where we have access and can run new wire easily.

Questions for the forum:

1- Is it worthwhile to change the existing breakers on the old ungrounded circuits to newer AFCI breakers? I'm worried about the condition of the old wiring in places that can't be inspected, and I wonder if a greater degree of protection can be achieved with AFCI breakers on an old circuit. The circuit won't be just plugs, but lighting, dimmers, etc. Is this a good idea?

2- Any other suggestions for easy safety upgrades to an old house, short of doing a major electrical reno??

Thanks in advance to the members of the forum for considering our questions.

Yes to all your concerns. Just make sure you pair the right hot with the correct neutral wire. If it is Romex I am sure there is a ground present but it is typically wrapped around the sheath and the clamp that holds the wires in the box holds it tight to the box for grounding. As you renovate un wrap the wires and twist them together ground the box and recptacles.

Romex hardly ever goes bad unless it is in a light box that has a bulb higher then the fixture calls for. Also remeber #14 gage is 15 amps and #12 is 20 amps. Good luck sounds like you have some knowlege:)

rickpantel
Re: Install Arc-Fault Circuit Interrupters to older wiring??

Thanks for the reply, Harry.

I think I used the wrong term in my question. I don't know what you would call the old style wires on the old circuits. The wires are solid copper wires, encased in some sort of rubber material, wrapped with some kind of braided fabric stuff, and then the whole bundle wrapped in papery material with a black, tarry-looking outer jacket. When I work with those wires in existing junction boxes, the rubber insulator is brittle and just shatters away. There is definitely no 3rd bare-copper bonding wire like you see in modern NM wire sheaths. There is no obvious black and white....just a dirty brown with maybe a hint of a different color thread, that has long faded away. This stuff would have been installed in the early 50's.

From your reply, I think that Romex was the wrong term. What would you call this old-style wiring?

Is it still a good idea to switch the circuit breakers to AFCI breakers on these old circuits?

Re: Install Arc-Fault Circuit Interrupters to older wiring??
rickpantel wrote:

Thanks for the reply, Harry.

I think I used the wrong term in my question. I don't know what you would call the old style wires on the old circuits. The wires are solid copper wires, encased in some sort of rubber material, wrapped with some kind of braided fabric stuff, and then the whole bundle wrapped in papery material with a black, tarry-looking outer jacket. When I work with those wires in existing junction boxes, the rubber insulator is brittle and just shatters away. There is definitely no 3rd bare-copper bonding wire like you see in modern NM wire sheaths. There is no obvious black and white....just a dirty brown with maybe a hint of a different color thread, that has long faded away. This stuff would have been installed in the early 50's.

From your reply, I think that Romex was the wrong term. What would you call this old-style wiring?

Is it still a good idea to switch the circuit breakers to AFCI breakers on these old circuits?

I would say type NM Cable (Non Metalic). Honestly before my time in the trade. I have seen very little of this cable. But you did mention you were in Canada?

AFCI breakers are just the answer. Perfect:)

Ernie_Fergler
Re: Install Arc-Fault Circuit Interrupters to older wiring??
Ravens53 wrote:

I would say type NM Cable (Non Metalic). Honestly before my time in the trade. I have seen very little of this cable. But you did mention you were in Canada?

AFCI breakers are just the answer. Perfect:)

I call it cloth Romex, for lack of a better term. Later versions also contained an 18 awg bare wire as a ground.
And yes the ground wire was usually wrapped around the screw clamp at each box by the sparky. My guess there is that most electricians at the time had no use for a new fangled ground wire.:rolleyes:

canuk
Re: Install Arc-Fault Circuit Interrupters to older wiring??

Eh? ... ground wire on early 50's vintage 2 conductor ?:confused:

Ernie_Fergler
Re: Install Arc-Fault Circuit Interrupters to older wiring??
canuk wrote:

Eh? ... ground wire on early 50's vintage 2 conductor ?:confused:

Two conductor with ground, yes. Too bad I don't have a piece laying around the garage that I can research on. The price per lb. of copper these days and all that...
Quite common in central Pa. The wiring might be from a later time frame, say the sixties. Please don't quote me on that though:D

canuk
Re: Install Arc-Fault Circuit Interrupters to older wiring??
Quote:

The wiring might be from a later time frame, say the sixties

Ah ... yes the sixities :eek: :D .

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