Why do my lights flicker when AC or appliances start?
Answer
Brief dimming can happen at startup, but repeated or severe flicker usually indicates voltage drop, weak connections, overloaded circuits, or service equipment limitations. It should be tested before it worsens.
Likely causes
Flicker patterns often reveal where the issue sits.
- Single room flicker: branch-circuit or local connection issue.
- Whole-home flicker: service-side voltage or panel-level problem.
- Flicker with major loads only: startup current + insufficient capacity or poor terminations.
Massachusetts context
Massachusetts homes with mixed-era wiring can show flicker under modern load profiles. Proper diagnosis should include load behavior, neutral integrity, and panel/service condition to confirm a code-safe correction.
When this is more than a nuisance
Call when flicker is frequent, increasing, or accompanied by other warning signs.
- Lights dim sharply when HVAC, oven, dryer, or pump starts.
- Flicker happens in multiple rooms or across the whole home.
- You notice buzzing, warm breakers, or intermittent power drops.
Start with General Residential services or return to the homepage to route the issue quickly.