Lights flicker when the fridge kicks on, where do I start safely checking this?

[ViktorArseid]

I’m a bit nervous asking this because I do not want to mess with anything unsafe, but I’m seeing my lights flicker when a big appliance starts. When the fridge kicks on or when the AC starts, the lights do a quick dip and sometimes a little flicker. It’s not constant, but it’s noticeable enough that it makes me wonder if I should be worried about something like a loose neutral or an overloaded circuit.

A specific moment was this week when I was in the kitchen and the lights dimmed right as the fridge compressor came on, and it happened again later when the AC started. It’s frustrating because everything still works, but the flicker feels like a warning sign. If you were giving a safe troubleshooting order for a homeowner, what would you check first, and at what point do you stop and say this might be a utility issue or a panel connection that needs a pro?

 

[Ironbloods]

One easy way to narrow it down without opening anything is to ask neighbors if they see dips when AC or fridges kick on, and to watch if your flicker lines up with heavy neighborhood load times. If it’s only your house and it’s affecting lots of lights across different rooms, that’s when I’d start thinking service connection or panel connection and get an electrician out.

 

[Alan]

Start by observing patterns without opening anything. Does it happen only on kitchen lights or on lights all over the house, including bedrooms and bathroom fans. If it’s only one area, it may be a branch circuit connection. If it’s everywhere, it points more toward service or main connections. Either way, avoid panel DIY if you’re not trained.

 

[PGB1]

Hi Viktor,
When any lamp in any room dims upon a load starting:
I've encountered this many times when the service entrance conductors are aluminum. The neutral/ground often either oxidizes or loosens from heat/cool cycles, creating high resistance The electrons from the lamps and the heavier load are all trying to escape through the grounding electrode system at once instead of back to the transformer via the service conductor.

Aluminum conductors must be prepared & installed properly & many people don't know how or skip prep.

It could also be a problem at the utility pole connection point or your service point. In the case of my house, the service drop is #10 AWG. Dimming happens. Often.

As mentioned by Alan, an electrician should investigate this. Please don't work this on your own. Let us know what you learned from the electrician.

Paul