Flickering lights - utility co. has been called - but I have questions for any electricians

Factual Questions
1

I called the utility company three hours ago but they aren’t here yet. In the meantime, I’ve realized the problem might be in the house and not from the transformer.

The lights started flickering late last night. This got my attention when I turned on the lights in the bathroom. Then I noticed they were also flickering in the living room and kitchen. I had been in the office where the lights were fine. They are also fine in the bedrooms. This happened a couple times and I did note that it seemed to start when I went in the bathroom but brushed it off. I thought maybe there was some work going on nearby as a result of the weather over the weekend.

Tonight when I turned on the lights in the house, I noticed them flickering again and called the utility company. Later the lights stopped flickering for about an hour. But when I went in the bathroom and turned on the lights, the flickering started again. So does this mean there is something wrong with that circuit in the house? Something that turning on the bathroom lights is causing? I’ve turned off all but a night light and the porch light that had been flickering and it has stopped again. I left on the porch light so the utility workers can see the house. But should I turn off all the lights on that circuit to be safe?

Should I try to find an emergency electrician or wait until morning? It’s 9 p.m. here.

2

I am not an electrician, but I had a similar problem a few years ago. My main breaker was wearing out. Sometimes the leads to the main breaker get loose over time, so you can try to tighten them (very carefully!), but you may need a new main breaker.

I called the the electric company and they cut my power, (removed my meter) and I replaced the main, then they replaced the meter. Problem solved.

You can probably wait till morning.

3

Call the utility, shut off any 240V breakers - stove, water heater, etc. if you have lost your neutral, the voltage can float up on one leg and blow any 120V appliances. I wouldn’t wait until morning.

4

I called the utility company back and they aren’t coming until tomorrow because “it’s not an emergency emergency” and there have been no other calls in my area. I’ve turned off all lights that were flickering. The circuit seems to run along the outside walls of the kitchen, dining room and living room into the hall and bathroom. I don’t think there are any electronic devices along the path. The TV hasn’t had any issues along with one lamp on the opposite wall in the living room. I’ll start calling electricians first thing tomorrow.

5

This^^^. It is very likely just a loose neutral connection in your breaker panel. Over time they can come loose even if originally correctly installed. It’s the first thing I’d look at. Should be a simple fix for a qualified electrician. Just takes a screwdriver and maybe an allen wrench and about 5 minutes. BUT DO NOT TRY TO FIX THIS YOURSELF IF YOU DON’T KNOW WHAT EXACTLY WHAT YOU ARE DOING. YOU COULD DIE.

As Fins said, shut off all your 240 volt “double” breakers (the big ones that take up two spaces). That should get you through until you can get an electrician to look at it.

6

That’s why I’m waiting on a professional!

I only have 6 regular breakers. To my shame, I never tested them to see which ones do what. And I don’t want to mess with anything right now and chance fucking things up worse.

7

You can easily tell the 240v breakers because they look like two switches connected together.

8

Agree. This happened to me and in checking my voltage it was fluctuating between 100 and 270. In was 3 in the a.m. and I was very fortunate the power company showed up in about 20 minutes. After pulling the meter and tightening the neutral lug, all returned to normal.

9

@aurora_maire Remind me where you’re located? Just wondering because of something I experienced last night…

10

I’m in Memphis.

The first number on my list was the well-loved neighborhood electrician and he is available this morning! He should be here in about an hour. I got about four hours of sleep. Fingers crossed that this is an easily fixed problem. Thanks for everyone’s input last night.

11

I had pretty much the same thing happen at my house after we got that winter storm last Friday.

Turned out to be a problem at the pole, one of the wires had come loose and was making intermittent contact.

Easy enough fix for the professionals, only took them about 15 minutes. NOT something I would even think about doing myself.

May need to wait for the power company.

12

Loose connection was definitely my first thought, too. Glad you have a trusted expert coming out.

Meanwhile, may I offer this oldie but goodie:

In my house there’s this light switch that doesn’t do anything. Every so often, I would flick it on and off just to check. Yesterday, I got a call from a woman in Germany. She said ‘cut it out’.’

— Steven Wright

13

Good to hear that this is being looked at ASAP.

Loose neutrals can happen on 120V circuits as well. I almost had a house fire due to a loose neutral that was a shared neutral for two 120V circuits. Luckily someone was home and turned off the power before a fire started, but I lost a refrigerator and a microwave that night. Although I fixed it since it was very obvious where the problem was in the panel, I had an electrician replace the entire panel soon afterwards.

Actually, though the fault (and a hot spot) was in the panel, it was the microwave that actually caught fire. In a way that was good, since it was spotted almost immediately. A fire in the panel or wall might have gone in unnoticed until it was too late.

14

The electrician came. I turned on all the lights and no flickering. Not one single flicker. He checked the box in the kitchen and the one outside and couldn’t find anything wrong. He didn’t think that the fact that it would start flickering after I turned on the bathroom lights was an issue but he checked the plug and light switch in there and they are ok. He told me to leave all the lights on and text him if they start up again. He is going to come back around 3:00.

15

Was it windy when they were flickering, and less windy now?

16

I think this is a useful article to help (mainly you) troubleshoot the issue:

If you have an older house with relatively low total amperage available at your panel, it’s not at all inconceivable that you could overload circuits enough to induce flickering but not trip an individual breaker.

Particularly with a few high-current appliances and if you happen to have old school incandescent light bulbs.

And/or the neighbor drawing a lot of current simultaneously. Any or all of the above could be happening.

Also, haven’t you guys been in a rather severe cold snap? Do your furnace and/or water heater draw electricity?

It might just all add up …

17

It wasn’t really windy but it was raining pretty hard. He said there is a spot on a wire outside that could have gotten wet but that putting tape on it wouldn’t help. I didn’t quite understand that so I’ll ask him again when he comes back. But it seems weird that if it was something affecting the wires outside, only one section of the house would be flickering.

And the utility company still hasn’t shown up. I asked him if I should cancel with them but he said it wouldn’t hurt for them to check the lines.

We were over Christmas but it’s been in the 60s the last couple days. I’ve got everything on, ran the heat a bit even though I don’t need it, microwaved some lunch, randomly turned on and off the bathroom lights and everything is fine.

18

That’s exactly how it played out with mine. If one of the 120V lines is not getting a good connection, then that side of the breaker isn’t getting power. My downstairs and outdoor lights were working, but the rest of the house (including the furnace on a -5F degree day) was out.

That sucks. Any time estimate? I was fortunate in that I reported the outage with the app (my computer and internet wasn’t functional), and they were out within a couple hours.

I did feel bad for the guy getting up in the bucket and going to the top of the pole in that weather, but that’s what they make the big bucks for. I told him I’d offer him a coffee or hot chocolate, but he’d have to wait for my power to come back on.

Just for reference: It was about 4 in the morning that the power first went out. I noticed as my laptop beeped as it does when it gets unplugged. Then the power came back about 10 minutes later and stayed on for about 15 before it went out again. It kept coming on and going out for a while, sometimes a few minutes, sometimes most of an hour, including periods where it would just start flickering rapidly. I figured this was all just because of the winter storm we were dealing with.

When I finally got up, I noticed that not only did my neighbors have power, but my basement and backroom did, too. That’s when I figured it wasn’t a problem that was going to resolve itself, and I reported the outage.

I went up to check on my business, to make sure it had power and didn’t have any freezing pipes, and by the time I got back home, I had a utility truck outside my house and a couple guys in high vis vests wandering around my yard. For the first time that morning, I was glad my power was out, as I would have felt a bit embarrassed if it was working fine after calling them out there.

But they poked around at the house and its connection for a bit, then said that the connection at the pole looked a little “squirrelly”, and went up there to fix it. After he was up there for a few minutes, he had the power back on as good as new.

IMHO, I think it’s more likely to be an external connection, both because it being outside gives more chances for something to go wrong, and if it were internal, your electrician friend would have more likely caught it.

Anyway, good luck, electrical problems can be frustrating.

19

I called the utility emergency number where I talked to people twice last night to see if I could find out when someone would be here. The woman wouldn’t even talk to me. She insisted I had to call the customer service line to check on a ticket. The wait time is 42 minutes. Grrr.

20

Most homes in the U.S. are fed by what is called a split phase transformer. Without going too much into the details, you end up with three wires coming in from the transformer, one from one end of the transformer, one from the other end of the transformer, and a third connected to the middle of the transformer coil (hence, “split” phase). The one connected to the middle of the transformer is your “neutral” wire and is connected to earth ground. Literally. As in it’s typically connected to a copper round that is pounded into the ground. The wires connected to either end of the transformer coil are your two “hot” wires.

If you measure between either “hot” wire and neutral, you get 120 volts. If you measure between the two “hots”, you get 240 volts. Hopefully this diagram will help to explain it. The diagram shows the distribution voltage as 7200 volts, but this varies. Anywhere between about 3500 volts and 12,000 volts is typical.

If you look at your breaker box, the breaker slots alternate between the two “hot” wires. In other words, if you go down the left side of the breakers, the first slot is connected to Line 1, the second slot is connected to Line 2, the third slot to Line 1, the fourth slot to Line 2, etc. If you have a 120 volt circuit, then the breaker only connects to one of the two hot lines. If you have a 240 volt circuit, that breaker is double-wide, and connects to two adjacent slots so that it gets the entire voltage between line 1 and 2 (240 volts).

This diagram shows a single breaker at the top and a double (240 V) breaker wired to a dryer at the bottom.

So your 240 volt circuits (dryer, oven…) will get connected to both Line 1 and Line 2. All of your 120 volt circuits should be roughly balanced, with half of them connected to Line 1 and half of them connected to Line 2.

If you have a bad connection on say Line 2, but no problem with Line 1, then all of the stuff connected only to Line 2 will flicker, but stuff connected to Line 1 will not. The problem could be at the transformer, at the electric meter, or at the breaker box. If it is truly only one circuit that is flickering, and not the entire Line 1 or Line 2, then it could be a bad connection at that breaker or it could be a failing breaker.

Another type of problem that you can have is if the neutral (aka center tap) connection to the home’s transformer has a bad connection. This can be really bad, because you will still have 240 volts between Line 1 and Line 2, but the neutral will tend to float between the two voltages. So if the voltage between Line 1 and neutral floats down to only 80 volts, Line 2 floats up to 160 volts (240 - 80 = 160, the total will always add up to 240). Obviously 160 volts is bad for devices designed to operate on 120 volts, so this type of failure can cause a lot of damage to lights, appliances, etc.

A broken neutral should be easy to identify. If you measure the voltages coming into the breaker box, you’ll see that Line 1 and Line 2 aren’t balanced. Any competent electrician should be able to test for that.

Distribution wires (the wires that go all around your neighborhood) often are not insulated. They are designed to get wet. No biggie. The wires that go from the transformer to your home typically are insulated, but if they have a bad spot on the insulation and get wet that won’t cause the symptoms that you are seeing. Snow and ice between wires can cause issues.

He’s right. It’s a good idea to have them check the wires.

One good thing that you can try yourself is to flip the breakers on and off, one by one. If you turn one specific breaker off and all of the lights that were flicking go off all at once, then you know that your problem was only on that circuit. Have your electrician look at that circuit. If one and only one breaker does not control all of the lights that were flickering, then the problem isn’t just one circuit or breaker, and may be outside your home.