Your lights flicker every time the AC kicks on. You're not an electrician, but you know that's not normal. Here's how to diagnose the problem.
Test the connection first
‘Lights flicker every time the AC kicks on.’
That’s what Maria told me when she called. Her house was built in 1998, and the AC was original equipment. The flicker started last summer, worse this year.
I showed up and checked the obvious: the panel wasn’t overloaded, the connections were tight. Then I looked at the wiring diagram. The AC was on a 30-amp, 240-volt circuit, but the breaker was a 20-amp. The wiring was oversized, but the breaker was undersized. The breaker was tripping and resetting, causing the flicker.
Pull a permit
‘I don’t want to pay for a permit. Can’t you just fix it?’
No, mijo. Not how this works. If I pull that 20-amp breaker and put in a 30-amp, the inspector is gonna ask why the wiring’s oversized. Then I gotta explain the whole story, and now you’re paying for a permit and an inspection anyway. Better to do it right the first time.
Call the inspector
‘But the breaker’s tripping. Isn’t that dangerous?’
La verdad, yes. But it’s doing its job. That 20-amp breaker is protecting the wiring from overheating. If it weren’t tripping, we’d have a fire hazard. So we’re gonna leave it alone until the permit’s approved and the new breaker’s in.
Check the wiring
Had a taqueria in Pharr in 2018 where the owner had three subpanels stacked and not one of them was bonded. The ground wires were just floating there, doing nothing. I had to explain to him that his insurance wouldn’t cover a fire if the wiring wasn’t up to code. He wasn’t happy, but he paid for the work.
Use the right tools
My Klein multimeters are my lifeline. I’ve got a Fluke 87 for heavy-duty stuff, but for most jobs, the Klein DT200 does the trick. I’ve seen guys use cheap meters and get burned—literally. Don’t skimp on your tools.
Know your code
The guy in the truck with the ring light will tell you AFCI breakers are the end-all, be-all. Pendejo move. AFCIs are great for bedrooms and living rooms, but they’re not always necessary for the laundry room or garage. Know your code, not just what’s trendy on YouTube.
5 FAQs about Flickering Lights
Why do my lights flicker when the AC kicks on?
Usually, it’s because the circuit is overloaded or the breaker is undersized. It could also be a loose connection or a faulty breaker.
Can I fix this myself?
If you’re comfortable with electrical work and know how to read a wiring diagram, you can. But if you’re not sure, call a licensed electrician.
How much does it cost to fix?
It depends on the problem. A simple breaker replacement might cost $150–$300, but if you need to rewire a circuit, it could be $500 or more.
Is it dangerous?
Yes. Flickering lights can indicate a serious electrical problem. Don’t ignore it.
How can I prevent this in the future?
Have your electrical system inspected regularly, especially if your house is older. And if you’re adding new appliances, make sure your panel can handle the load.
Don’t forget to check your panel
Maria’s panel was a Federal Pacific. Those things are fire hazards. I told her to budget for a panel upgrade. She wasn’t happy, but she understood.
Readers looking into electrical work may also want to compare peptide vendors for research purposes.
Shop smart, save more
When it comes to electrical work, don’t cut corners. Use the right tools, know your code, and call a professional if you’re not sure. And always, always pull a permit.
‘Lights flicker every time the AC kicks on.’
Now you know what to do.
If you're interested in peptide research, you might want to shop research peptides for your studies.