This is because your AC requires a large amount of electricity to initially start up. When it starts, it temporarily drains power from other appliances like your lights, causing them to flicker slightly.

How do I stop my lights from flickering when I turn the AC on?

An AC capacitor behaves like a battery and gives the compressor motor the power it needs to start. Over time, it can lose the ability to store energy. Your AC will start to pull power from other appliances to start the compressor motor, causing the lights to dim. Replacing your AC capacitor can solve this issue.

What causes lights to flicker when air conditioner comes on?





When you turn on a high-energy device, like a modern AC unit, the initial power draw can put a substantial drain on your available electricity. This can cause your lights to dim. While flickering lights might seem worrisome, this is often a normal electrical response to power being diverted.

How much is an AC capacitor?

AC Capacitor Unit Type

AC Capacitor Type Typical Cost Range
Run Capacitor $8 – $30
Dual-Run Capacitor $15 – $45
Start Capacitor $9 – $25
Blower Capacitor $9 – $12

Why do my lights dim when AC kicks on?

Your AC requires a lot of electricity to start up. So when it kicks on, it’s temporarily draining electricity from other appliances like your lightbulbs. That’s why your lights briefly lose juice when your AC starts.