Is It Normal?
A very brief, barely noticeable dimming when the AC compressor starts is common and generally harmless. However, call Ocean Wire Electric if:
- Lights dim significantly (more than a flicker)
- Dimming lasts more than 1-2 seconds
- Other appliances are affected
- The flickering has gotten worse over time
Top Causes
1. AC Compressor Inrush Current
When an AC compressor starts, it briefly draws 3-6x its normal running current. This "inrush" causes a momentary voltage dip on the circuit.
Solution: Hard Start Kit installation on the AC unit.
2. Loose Neutral Wire at the Panel
A loose neutral connection at the main panel creates resistance, causing voltage to fluctuate when large loads start.
Solution: Panel lug tightening — a quick professional fix that eliminates a serious fire risk.
3. Undersized Service Entrance Wiring
If your home's service entrance wires are undersized for your current load, voltage will sag under demand.
Solution: Service entrance upgrade.
4. Failing AC Capacitor
A weak capacitor makes the compressor work harder to start, increasing inrush current.
Solution: Capacitor replacement (HVAC technician).
The Hidden Danger: Loose Neutral
A loose neutral wire is not just an annoyance — it can cause voltage imbalance that damages sensitive electronics and creates a fire risk at the panel. If your flickering is accompanied by lights that seem too bright in some rooms and too dim in others, this is a serious warning sign.
Stop the Flicker Before It Becomes a Fire
Contact Ocean Wire Electric for diagnosis.
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