Long story, so pass if you're not in for a long read.

Probably a ton of posts on this but anyways...

My neighbor has a 1950s house with a 60 amp service. Someone replaced the panel with a 100 amp main breaker panel.

Neighbor told me the lights were blinking when the central air came on. They wanted the top half of the service upgraded anyway and I assumed that would fix it. I never actually saw any blinking.

After I upgraded top half of service to 100 amps they said lights still blinked. I did find a loose wirenut on the hot side in one box that caused a living room lamp to blink when I moved the wirenut. Didn't fix the issue.

At the main breaker I measure right at 240 volts and 120 to both neutrals. At the living room lamp I measured 117 volts. When we turned on microwave oven the voltage went up to 119 volts. Didn't check to see if they were on opposite phases or not.

The garage is on it's own 2 pole 30 amp circuit with a sub panel. They tell me lights blink there too but I didn't see it.

I'm thinking since blinking is on different circuits and all connections at panel and meter are tight, it must be a power company issue. Will be calling them tomorrow.

Anything different I should have done? Any magic blinking light troubleshooting techniques I need to be aware of?

Thanks for reading.

Sent from my SM-G930V using Tapatalk