We had the internet technician out to our house for a modem that wasn’t working. While the tech was here, something happened and various appliances, including some very expensive ones, were fried. We are now going to have to have a new air conditioner and heater installed, plus the dishwasher and oven are shot and some upstairs outlets are also shot.
I know I’m “asking on the internet,” but I am so confused. My dad is pretty OLD and is the one who dealt with the technician, who told him that it was the window air conditioner upstairs that fried everything and it was an electrical emergency and our house could burn down. And we should get an electrician out here. And there was a melted cable of some kind in the backyard.
So my dad had an electrician out the next day, who did pretty much nothing, as far as I can tell.
Today I asked on Reddit (I know), and they all said the internet technician is probably correct and we have a “loose neutral” that could burn the house down, and we should get the power company to check us out.
So I contacted the power company, who called a little while ago and said they would check some things, remotely I guess, and call back. But will that help diagnose a “loose neutral” or whatever? What or who do I have to contact to figure out if:
There is still a horrible problem that has not been diagnosed yet.
The internet technician was correct.
The internet technician did something to cause this (which Reddit said was not possible).
Everything is okay now and there was just something faulty with the house, now it’s fine (somehow) and we will have to replace the fried appliances but no more danger?
Obviously I know nothing about how internet cables and electrical cables work.
What country are you in? Turn off the main circuit breaker and get a licensed electrician to look at it ASAP.
Assuming you have a split-phase system such as found in the U.S. and Canada, over-voltages and under-voltages can certainly be caused by a loose connection (or no connection) on the neutral.
If indeed you have a bunch of damged or dead appliances you need a pro on-site. Not even a pro here (which I am NOT) can do your problem justice from this distance.
There can be whole-house loose neutrals the power company might be able to diagnose remotely. There are also in-house loose neutrals they’d have zero ability to see.
IOW, a clean result from them is nice, but not dispositive.
My advice is switch off the main breaker, then call your local electric utility and tell them there is a suspected loose neutral problem at the house. Most utilities will roll a truck fairly quickly for that since it’s a potentially dangerous situation. This is difficult to diagnose remotely because most residential meters aren’t connected to the neutral. If you actually have an open, or intermittent neutral, the voltages in the house receptacles can swing from 0 to 240V instead of staying at the nominal 120V.
They will be able to rule out a loose neutral problem somewhere between the transformer and meter base, likely with something like the Beast.
Yes, we’re in the US. But this is very overwhelming. Nobody we’ve talked to, except the internet tech, seems to be in any particular rush to check for something serious.
The way most homes in the U.S. work is that they are fed from what is called a “split phase” transformer. There is a transformer nearby, typically either up on a pole or in a box in someone’s yard if you have underground lines. That transformer will convert the distribution voltages (anywhere from about 3,000 volts up to 12,000 volts, sometimes even higher) down to 240 volts for your home. A single transformer typically feeds 3 or 4 homes.
The reason they call it a “split phase” transformer is because it has a center tap on the home side’s coil. This center tap is grounded, and it literally becomes the “earth ground” for your home. Literally, as in it’s usually a copper rod that is driven several feet into the ground.
The way this works, is that you have 240 volts between the two ends of the transformer coil, and 120 volts between either and and the center tap. Your breaker box typically has connections that go like this down each side:
A
B
A
B
A
B
etc.
A and B are your two lines (the two ends of the transformer coil) coming into your house. Between A and neutral is 120 volts. Between B and neutral is 120 volts. Between A and B is 240 volts. So your 240 volt appliances typically will have a breaker that takes up two slots, so it can connect one wire to A and the other wire to B. All of your 120 volt loads should be roughly balanced between the A and B breakers (it doesn’t need to be exact).
What happens when you have a loose neutral? You lose that connection somewhere, typically between the breaker box and the outside transformer. You are still going to have 240 volts from A to B, but the “neutral” inside your house is no longer attached to ground. The voltage on your neutral will no longer be earth ground. It will be the ratio between the amount of current flowing on the a side to the amount of current flowing on the B side. But you still have 240 volts total between A and B. So, as an example, you could have only 80 volts between A and neutral. That means B will go up to 160 volts (240 minus 80, since A to B is always 240). 160 volts is really bad for devices designed to run on 120 volts. Things can easily be damaged and catch fire.
This is exactly true.
If your first electrician couldn’t find an issue, you need to get a competent electrician.
Yippee! Reddit finally got something right.
They remotely monitor the voltages on the distribution lines, so if there is a line contacting another line and putting a much higher voltage onto one of their lines then they should be able to detect that.
Most modern power meters also measure voltage, current, power factor, and all sorts of things. A loose neutral will usually show up as a voltage imbalance.
1. There is still a horrible problem that has not been diagnosed yet.
Start bugging your power company.
2. The internet technician was correct.
Possibly. Can’t tell just from what you have posted.
3. The internet technician did something to cause this (which Reddit said was not possible).
It’s not impossible. But it’s not likely either.
4. Everything is okay now and there was just something faulty with the house, now it’s fine (somehow) and we will have to replace the fried appliances but no more danger?
Electrical things don’t just mysteriously fix themselves. I find the “melted wire” description particularly alarming. Some of your “broken” appliances might not be broken, but there are some major issues that need to be fixed here.
I found this video which may help you visualize what is going on. Note that when the lights get “bright” in the video is when things would overload and burn up in the real world. The video gets way too technical at the end but the first part should be good to help you visualize what is happening.
Most modern power meters also measure voltage, current, power factor, and all sorts of things. A loose neutral will usually show up as a voltage imbalance.
Residential meters (specifically Form 2S) don’t connect to the neutral, so the meter itself can’t measure the individual 120V legs. These meters aren’t that helpful for detecting open neutrals.
I find the “melted wire” description particularly alarming.
Yeah, that’s a bad sign, and like you said, electrical problems rarely fix themselves Could be a cable TV coax shield that was conducting neutral current which melted the insulation, as described here:
Do you have more information about the melted cable in the back yard? Just a short piece of cable or a run from the house to the garage or something? I can’t figure out how a melted cable gets in the yard.
See the link my my prior post for one way that can happen. With ground and neutral connected at the meter base, it’s possible for neutral current to find alternate paths back to the transformer. In that example, two houses shared the same utility transformer and both had cable TV. The braided shield on the cable TV coax (which is also connected to ground at each house) ended up carrying the neutral current for one house, which caused it to overheat and melt the coax insulation.
No, I don’t. I was at work when all this happened, and my dad is the one relaying all this information.
I don’t really have the ability to just keep trying to get some halfway decent electrician who knows what they’re doing to come to the house. Like, I don’t have much extra money, especially not to get these non-answers from random technicians that don’t help. The power company never called back.
I would call someone if I thought there was anyone with the knowledge and willingness to actually come out and fucking do something. Feels like I’m in crazy town.
Keep calling the electric utility until they send someone. They need to rule out a loose neutral from their transformer to the meter base (or fix it, if that’s the problem - and if it’s there, only they CAN fix it). These problems can be intermittent without any symptoms sometimes, just having an electrician poke around in the house may not catch that.
I feel the OP’s pain. A electrician was wiring a whole house generator into the main panel of my parents home. Something went wrong and he fried the electronics in the house. That include the hvac control board.
I never heard what wrong. May have been a loose neutral. Generac includes a special Switch and subpanel for whole house generators.
His company was insured and my parents eventually got paid for damages. Money can’t make up for the stress and aggravation.
I will keep bugging the power company, but this is very stressful. I would never have thought it’d be so hard to just get some damn answers after some kind of electrical problem fries everything.
I don’t know that it’s a loose neutral as opposed to some other horrible electrical problem, but that’s what Reddit suggested.
I believe it was the main number. I wasn’t sure what counted for the emergency number. If I call them and they come out and say it was nothing, do they get mad and charge you?
Do they have to come out to check that? The guy we did talk to checked some things remotely, but I don’t know what. I couldn’t get in the phone because most of the phones on our landline have also been fried.
Could be a cable TV coax shield that was conducting neutral current which melted the insulation, as described here: