Old house-what gauge wire?
#1
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Old house-what gauge wire?
Hello,
I have a house that was built in 1931. I need to splice in at a junction box, but I can't figure out if the old wiring is 14 or 12 gauge. It has a cloth outside and some kind of brittle coating over the wire. There is 12/2 run to it right now, but I'm not sure that's the right thing. I've attached a pic. Thank you!
Tom
I have a house that was built in 1931. I need to splice in at a junction box, but I can't figure out if the old wiring is 14 or 12 gauge. It has a cloth outside and some kind of brittle coating over the wire. There is 12/2 run to it right now, but I'm not sure that's the right thing. I've attached a pic. Thank you!
Tom
#2
The cloth wire appears to be 14 gauge. More importantly, what is the amperage rating of the breaker/fuse that protects the circuit? If it is 15 amp, you're OK. If it's 20 amp, you need to replace the cloth covered wire with 12 gauge to its destination/origin.
#3
I have a house that was built in 1931. I need to splice in at a junction box, but I can't figure out if the old wiring is 14 or 12 gauge. It has a cloth outside and some kind of brittle coating over the wire. There is 12/2 run to it right now, but I'm not sure that's the right thing.
#4
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Hi Chandler. There is a mix of breakers in the box, some 20 but most 15 amps. The previous owner has both 12/2 and 14/2 running from the box and then tying into the old wire. I'm not comfortable with this. The pic shows 12/2 running from a 20 amp to the old wire, which then carries on into the house.
Thanks!
Tom
Thanks!
Tom
#5
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Just keep in mind that you cannot extend an existing ungrounded circuit
Thanks!
Tom
#6
As said check the breaker. If you have the possibility of a mix of #14 and #12 change the breaker to 15a if it is 20a. As said it isn't code compliant to tie new wire to it for a circuit if the existing wire doesn't have a ground.
#7
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Thanks Ray. That changes my schedule! I have what I have in regard to tying into ungrounded wire, but I'll switch out the #12 for #14 and bump the breaker down to 15a. There is one other new wire to old tie-in that I've inherited that powers the main portion of the house, and I'll swap that out as well.
I don't think I can afford an electrician to change out the old stuff, so short of what I'm doing, any other things I can do to make the situation safer? I'd appreciate your thoughts.
Tom
I don't think I can afford an electrician to change out the old stuff, so short of what I'm doing, any other things I can do to make the situation safer? I'd appreciate your thoughts.
Tom
#9
Just to add. The reason we are telling you to downgrade your breakers is if you are protecting the circuit with a 20 amp breaker, leading with 12 gauge wiring, then your 14 gauge becomes your fuse, and it most likely won't trip the 20 amp breaker when it overheats and possibly causes damage. Just for info.
#10
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
Thanks Chandler, I understand why you are saying that and I appreciate it. I don't particularly want another job (got plenty) but it's worth doing right when it comes to electrical...even if it's a bit of a pain in the butt.
I appreciate the wire stripper tip, but it seems that the old #14 wire I'm pulling out seems thicker than the new stuff. Is it just me smoking crack or is there a difference?
Thanks Again,
Tom
You can check the wire gauge with a pair of wire strippers or against a known size piece.
Thanks Again,
Tom
#11
The wire gauge standard has been the same for as long as I know. The insulation thickness and composition has changed though.
#14
Yeah, I had an inspector call me out on a bathroom wiring job once. He was 45' away from a bathroom telling me I had to install 12 gauge in the bathroom. This was before they went to colored sheathing. I had to actually take him to the bathroom with my Kleins and strip a wire for him to prove it.
#15
Is the 12/2 running from a 20 amp too much for the old wire running into the rest of the house and should it be 14/2 on a 15 amp?
#16
Member
Thread Starter
Join Date: Apr 2013
Location: United States
Posts: 10
Upvotes: 0
Received 0 Upvotes
on
0 Posts
The deed has been done! To be on the safe side I switched out the #12 for #14 and popped in a 15a breaker in place of the 20.
Thanks everyone for your help and advice.
Tom
Thanks everyone for your help and advice.
Tom