Need help identifying type of 240 wires
Need help identifying type of 240 wires
Hello,
I have been doing a lot of work remodeling a house I bought. The house was in really rough shape so I was expecting a good bit of work but the last owners laziness and incompetence has really made things worse.
They had the house split into two apartments and we are converting it back to a single home unit. We knocked out a wall and installed new stairs to connect the top and bottom floors. Next we are converting the upstairs kitchen to a laundry room. We have been using the makeshift room for a few months, but we are getting a new washer and dryer. Our current dryer is a compact electric dryer that runs on a 120v outlet. The new will be a standard electric dryer and need a 240v outlet. There is 240v outlet in the room for a range. I am going to pick up a new breaker from lowes with the proper amperage but wanted to check everything else first and I think I ran into an issue with the wire itself.
There are 3 wires, which matches the outlet so I am assuming it is supposed to be 2 hots and a neutral. However, upon closer inspection there is no insulation on the neutral. I peeled back more of the larger insulation around all 3 wires but the neutral wire is uninsulated like it was a ground. Now, I have encountered this in the house elsewhere. Most of the outlets have grounds cut off, but a 3 way switch didn't have the second hot wire so they used the ground as the second hot. I got that "fixed" (I unhooked everything and made it a single switch/light circuit and eliminated the second switch). But I don't know of any 240v wire combinations that would only be 3 wires and include a ground. The wire is definitely thick enough to be 240v wire and each individual wire has multiple "threads" like a 240 wire would. But it is older wire as well so I am not sure if it is just that old that they didn't insulate neutrals when they did this. Is this wire safe to use?
A second, and more minor question, deals with a separate circuit. The house electric is still split and I pay 2 bills, one for upstairs and 1 for downstairs. The upstairs does have an outdoor AC unit on it as well that was installed after we moved in by an HVAC tech so I am trusting that to be installed right. But the entire box for the "upstairs" has 4 breakers. There is a 50amp, 40amp, and 20amp double pole breakers and a 10amp single pole. The 10amp controls a single light and one of the 240v breakers controls the AC. Another controls the range/future dryer outlet. The The 20amp double pole controls everything else upstairs which is ALL 120v. There are a few lights and all of the outlets. Is that safe? Is there a reason to do that? The upstairs is pretty small if that makes a difference, I have just never seen a double pole breaker used for a 120v circuit even if it is pretty large.
Edit: I made the original post on my PC due to the size but I’m adding some pictures from my phone
Edit 2: I am going to buy and run new wire with the new breaker. I showed a picture to my dad and he said nothing matters because that’s an aluminum ground which means the wire needs replaced due to its age regardless. So even if it’s wired wrong now, I am stripping the wire out and putting a new wire and breaker in so it should be done right
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That wire looks absolutely ancient. I would call it a fire hazard and just replace it outright.
Shouldn't it just be the 2 hots and the ground though? 240v doesn't use an extra wire afaik, unless you're thinking 3phase or something.
To your edit, it should be 2 hots and a neutral is my understanding. Hots deliver electric and neutrals complete the circuit back to the back. In newer wiring the 4th is the ground but a 240v 3 wire has no ground. However, if it is a neutral it should be sheathed and individually insulated.
That being said, I’m not an electrician and most of this is just what I’ve learned from replacing outlets and rerunning 120v wire in this house. If an electrician wants to tell me I’m wrong I’m all ears
If you’re in North America, which I assume you are based on the 120v wires, then your assumption about 240v power is a bit off. Both wires can be a hot (120v) wire, 180° out of phase from each other, so they add to 240v. In this case, a neutral wire isn’t necessary to carry the current back, the other hot wire does that. A neutral wire may be used, but then there would be 4 wires.
The ground wire and the neutral wire actually connect to each other in the panel, but it’s not safe to use a ground wire in place of a neutral, so definitely don’t wire it to the neutral on the outlet.
If you are unsure of what’s going on with this set of wires, you should really call an electrician to help. Wiring a standard 120v outlet is something a homeowner can do, but identifying an old 240v cable on a dubious circuit is definitely something a qualified electrician should do.
So, I have a problem with electricians. I’m running out of them lol. I’ve had 4 out already for other projects and I get quotes and in 2 cases even paid the first payment but no one actually shows up to do the work. So I have just been doing it myself.
That’s said, my step dad does a lot of electrical work so I do have a bit of help even if he’s not a full on electrician. He’s has tons of tools for this type of work and makes most identification pretty easy. He took a Quick Look at the picture and he said it needs replaced based on the fact that it has an aluminum ground so I am just going to run all new wire. At least I know now that it will be the right wire
Just be careful!
Always! I’ve been doing a lot of work but I still don’t mess with safety. Obviously the main will be shut off and I won’t be doing the work while home alone in case something does happen. But since it is 1 breaker, 1 wire, and 1 outlet all being replaced it does seem to be a pretty straight forward replacement
The two hots give you 240 across them, but in North america an appliance may run 120 for standard control functions and 240 for heating functions, so in thise cases you need a neutral to provide a 120 pathway. you will see 240 stove appliance plugs have 4 prongs. 2 hot, 1 neutral and a ground. That wiring looks like a time before grounds were used.
Yeah, my first thought was to come into this thread and answer "I've identified it as the kind you replace"
Look at the wires in those pairs, they look like they're falling apart from each other. Do you really want to risk an area in the wall where one of those wires being thin/having strands broken which is going to cause it to heat up inside your wall?
This has fire hazard written all over it. Just replace the wire and stop trying to take the easy way out. You'll thank yourself later when you still have a house to go home to.
It does look bad and I plan to replace it regardless. I’m more so wondering if it needs replaced now. Wire is expensive and replacing this will be pretty extensive as I would need to tear out horse hair plaster to unstaple it from the studs. I’m not 100% on if it’s stapled or not but it’s tough to move and the other wires I replaced were stapled down so we had to tear open the plaster and run them that way. This would be going from 2nd story to basement through kitchen behind the sink so it’s not a quick job. If it needs replaced now I’m gonna need to cancel the whole weekend
I'm not an electrician, please consult with one if you're unsure.
I think Shadow is right on both counts.
The wire is very old. Personally, I would rip it out, but that is a risk assessment you have to make.
A 240V circuit, in North America, gets there by having two hot wires one on each of the 120V circuts from the transformer in the street. So no neutral wire is needed to complete the circuit. If you want to think about electricity "flowing" it flows from one pole to the other (instead of to the neutral in a 120V circuit). The unshielded wire is your ground.
This is a decent guide: https://www.thespruce.com/installing-a-240-volt-circuit-breaker-1824649
Please make sure you understand their point about what the main breaker does and does not disable.
Best of luck, looks like you're tackling a tough but fun project.
They are right. I was wrong. But the wire is getting replaced regardless. My step dad does a good bit of electrical work and said he doesn’t trust an aluminum ground on a 240v outlet
Can you just snake some new wire and not tear out the old wire? Not sure if legal or kosher, but it might save some time and effort.
Snaking wire without a guide for that distance is extremely tough. The normal way to swap out wire would be to tie the new wire to the end of the old and the pull the other end of the old. Since you can’t pull the old (it’s stapled and secured) you can’t pull the new through behind it.
Yeah I Gotcha, wire isn't cheap.
That uninsulated wire should be ground though, not neutral afaik.
wire isn't cheap.
Neither is a fire.
I think old style wiring had bare neutral in those 240 wires. It is the path back and shares a ground connection in the panel. I don't know the safery of insulated neutral vs non insulated, but I have seen panels with uninsulated neutrals. And The ground bar on modern equipment is also attached to neutral bar. I don't have enough electeical theory knowledge to explain why / how it is that way though
The insulation protects the stuff outside the wire from catching fire. The wires get hot while carrying a load. Neutrals always carry a load once the hot is powered on. Grounds only carry when something goes wrong such as a power surge. They carry excess electricity the neutral can’t handle and usually significantly less so they don’t get as hot. There’s no reason not to insulate a ground, and it arguably is safer, but the amount safer is noticeably less considering the extra cost. For a ground to get hot enough to catch something on fire several other safety measures would need to fail. In that regard it’s not necessary.
Yeah I think in the old wire scenario the two live wires were insulated and bare neutral sandwiched in them with an outercasing could have been their compromise on insulating all of them. But if you use 240 the neutral is not used unless it is wired as a 3 phase circuit. But what i meant by not understanding electrically theory is why bare ground and neutral join at the panel. i.e. purpose of a ground wire if you already had something reaching ground via the neutral connection in the panel to the ground rod or piping.
