I have a commercial space with recessed ceiling lighting. There's 3 lights in the front, 4 down the hall, and one in the bathroom (all on one breaker). Randomly throughout the day, they'll dim/flicker and sometimes even turn off for hours at a time. We've had 2 electricians look at it with no success.

The first electrician said he tightened wires in a few of the fixtures in the front, which helped for a while, but ultimately the problem came back the next day.

The second electrician checked our panel and ended up following it to the bathroom fixture, where he said the wires were loose in a junction box. He tightened those up and the problem was fixed for a bit, but the issue soon returned.

I'm reluctant to keep paying them to come back and keep looking (for what could be for hours) and still not fixing it again. Is there a chance that this problem is caused by loose wires in every fixture? Or is there something weird going on here?

  • There is a loose connection somewhere. Or multiple loose connections. Could also be a bad backstab on the breaker if it’s that type of breaker. You can usually diagnose that by just wiggling the breaker after it goes off.
    – Tyson
    Jan 23, 2018 at 23:11
  • @Tyson That's what I was afraid of. The second electrician said if it started dimming again, he'd probably have to come back and tear the ceiling apart and check every connection. Wiggling the breaker doesn't do anything. I'm hoping out of 2 professional electricians, at least one of them started by checking the breaker.
    – Aaron
    Jan 23, 2018 at 23:20
  • I would say loose connection also, rare for a breaker unless the zinsco or FPE brands but it happens, I would be looking for a backstab in the mess they are usually where I find the problem. It is hard to find an intermittent problem unless we are there when it happens, if this is the case I could use a tracer and locate the exact location. It shows through the wall where the failed circuit is. However if back stabs were used a new weak connection may develop after that one is fixed, this is why some electricians will not use back stabs. A greenlee cs8000 circuit tracer can find bad spots.
    – Ed Beal
    Jan 23, 2018 at 23:26
  • Consider your claim “every light on the cicuit" that alone says it's something at the beginning of the cicuit.
    – Tyson
    Jan 23, 2018 at 23:38
  • 1
    @Tyson I think that's what the 2nd electrician found. He followed the conduit from the panel which goes to the bathroom fixture first. He said there was a mess of wires that had bad connections. I was hopeful when he fixed that, but it's still no good. I'm sitting in the dark as we speak haha. No joke, they get worse and worse and eventually turn off completely right as night comes around.
    – Aaron
    Jan 23, 2018 at 23:43

2 Answers 2


Ok I figured I would give this a shot. First I like Harpers suggestion. It's important to know if they are all doing this at the same time or randomly. Second what type of light bulb are you using? Incandescent, fluorescent, or LED. This is important to understand if the problem is consistent with the lamp.

Finally, except for the dimming, you are describing what happens to recessed cans when the integral thermocouple begins to weaken in recessed cans. These are installed in all commercial cans to protect from overheating. If you disassemble the can trim you will be able to see it mounted on the side of the can assembly. The only way I know to repair it is to contact the original manufacture and replace the assembly.

Hope this helps, good luck.

  • The first and second electrician did some stuff "which helped for a while" - If you're correct what actually helped was having the breaker off for a while. Even secure aluminum wire connections can last for decades. Secure connections don't go bad in a matter of hours. At this point I'm wondering if they're wired in series, or what 'worked' was tugging on adjacent wires and never actually finding that bad connection; "mess of wires" leads me to that conclusion and that it's still an intermittent problem.
    – Mazura
    Jan 24, 2018 at 22:22
  • @Mazura The 2nd electrician came back today saying he replaced the breaker in question and that should've fixed it. It didn't really seem like a breaker issue at first, but I mentioned it to him and he checked it. He said it was charred. I'm a little surprised the first thing he checked wasn't the breaker. I'm still awaiting successful results. If it was just a bad breaker, I'm going to feel pretty stupid for bothering you guys.
    – Aaron
    Jan 25, 2018 at 1:44
  • @Aaron - I'd be surprised. I've never come across a bad breaker that the toggle switch still worked on. I'm curious, who manufactured the panel and what breakers it takes. I'm guessing not Siemens or Square-D... You should verify that they are using the correct breakers. And if the existing ones all are; wonder when the rest of them are going to fail.
    – Mazura
    Jan 25, 2018 at 2:06
  • @Mazura Replacing that breaker seemed to fix the issue. Both the panel and breaker are Square-D. Like you said, I'm worried something will cause the rest of the breakers to start failing one by one. Thanks for your help.
    – Aaron
    Jan 29, 2018 at 23:04

It looks like replacing the breaker in question fixed this issue. Even the electrician was surprised that the breaker seemed to be in working order, but ended up being the issue anyways. Thanks for your help, guys.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.