Which Wire is the Hot and Which is the Neutral in an Old House? How to Tell and Stay Safe!

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[aaront]

Voice reminds me of Scotty Kilmer. Good info too 👍

[feathermerchant]

Instead of electrical tape, I've used white and black heatshrink. It also helps slow further deterioration of the old insulation.

[billhandymanbill]

Nice and clear video! The only thing I tell your viewers is the insulation on electrical wire shown is called “Cambric” which is a rubber insulation covered by a cloth covering and that when the rubber dries out it crumbles and the cloth covering also disintegrates leaving bare wires exposed possibly causing a short circuit. That is why it is super important to over the wires with color electrical tape.

[davcot]

Another great vid. I see this issue a lot in Boston old homes. Perfect application for the wago nuts.

[farmerdave]

That's the reason I use black and white liquid electrical tape. I paint the wires the proper colors. Works real fine, lasts a long time.

[thomasdragosr.]

I can remember working in homes that were wired in the 1920's and before. As soon as you touched that old wire the insulation would crumble off. It would have been nice to have WAGO's back then, less stress on the wire when making splices.

[libertarian]

Good choice in non-contact voltage detectors; the Fluke is by far the best I’ve ever found. While these are good they’re not cheap; I believe in spending money where it makes sense and these make sense.

[JillofAllTrades]

VERY helpful. I was just crawling around in the attic and went downstairs to disconnect a light fixture from below so I could require it. I promptly forgot which wire was hot and which was neutral. I could guess but thought I’d be safe and double check. Thanks Bill!

[apagan]

As always Mr. Sparky, you're the man! I can always count on you to learn about electrical wiring. 👍

[buddyboyx]

Good job. Very helpful. Those little pen testers to show live wires are very cheap and very helpful.

[davidkozal]

This video was more than helpful being I have this type of wiring in my late 50’s home. Thank you for sharing your knowledge.

[BearMeatDinner]

Just did a switch for our house 1902. We are the 2nd owners! ❤80 plus years in the family.

[richardzapor]

I have been using this method for years. I would just add that often the insulation on old wires is badly deteriorated especially if you are dealing with older knob and tube era wire. In those cases i put shrink wrap as far on the wires as possible then use a small heat gun rather that a flame to shrink the tubing. Then I mark the hot feed to the box with a black tape flag back far enough back that it will not get in the way of of the wire nut or wago .i also put a white tape flag on the primary neutral in the box . Also good to look the wires over especially stripped ends to see if the copper has been nicked such that it is likely to break as you are shoving back in the box . And if there are just too many wires in the box i will try to put an extension on it or change it to a 2 gang old work box if necessary or a deeper single gang box. Some times you can use Wiremold system boxes to get around some overcrowding problems . Those non conduct current testers are great and essential tool in my bag! Also good to take a picture of the wires and connections in a box when you first open it so you duplicate what is there and working when putting it back together, as long as you find that what is there originally is safe . As i am sure you know sometimes those “rats nest “ boxes can be a nightmare to unravel and figure out .

[patthesoundguy]

I love the use of the lever nuts for testing purposes!!! I think that is a very safe way to get the meter probes on there with very little chance of them shorting out. I have clips that slide on over my meter probes but I like the lever nut idea. I'm going to pick some up. Thanks

[Ulbre]

I thank you and other you tubers for this information. I built a house in Thailand almost 20 years ago and I have since discovered that there is absolutely no conformity to wire colouring through the entire house. There's probably about 80 elec outlets and switches throughout the property and there are just so many differences that I decided to start taking apart each box and colour code and mark each course I had to learn how to identify each wire using a I thank you and the others for teaching me how to do all of have done about 10% so far, so still a way to go, but I am also making a log book for each and every plug & sw which will help both me and any future owner down the track.
Cheers from Chiang Mai :) :) :)

[jt]

I know a electrical but I like how you get real simple with it so people who know nothing can actually understand what you're meaning.

[AerialLensVideo]

Well done -- THANK YOU!
It is possible -- even LIKELY, out of so many views -- you saved some folks from a shock, a fall, or even worse. I live in an old house with a good bit of "knob and tube" remaining (some are even fused circuits) so definitely appreciate your video.

EDIT: Both my wires at a ceiling fixture show hot using a little detector like yours (mine blinks rather solid light). Now what?

[garybrown]

i you don't have test instruments & don't want to buy them, take a rubber pigtail lampholder, attach 1 lead to a metallic cold water pipe. the other lead to the suspected hot wire. the lamp will light on the hot wire, not on the neutral. this is also very useful when testing knob & tube wiring in older homes. bear in mind in the knob & tube days, the neutral was switched, not the hot.

[kenbrown]

and if you're lucky, the guy who built the house didn't leave the hot unswitched and control the fixture by switching the neutral - which would make it so a reverse wired fixture can ALWAYS be a shock hazard.
and that is why DIYers are ALWAYS advised to turn the power off at the breaker.
my last ditch trick, if I am not happy with the readings I'm getting, is to plug an extension cord into a known correctly wired receptacle - even if I have to install a temporary power cord from the panel - and use that to provide my definite hot and neutral references. I've had times when induction made it hard to get a clear reading from a non contact tester.

[AerialLensVideo]

THANK you!
Something I HAD to know in my old house, and YOU provided the answer, fast and easy.