Lights: Flash Off Flash High

Potterton Lights: Flash Off Flash Fault Code

Also written as LIGHTSFLASHOFFFLASH — same fault.

The Potterton Lights: Flash Off Flash fault code means: your boiler is receiving an insufficient amount of electricity to operate correctly, which is usually caused by an issue with your home's power supply rather than a fault within the boiler itself.. It appears on 5 Potterton models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Low Electrical Supply. Incoming Voltage less than 180V. Check System Controls & System Wiring. Otherwise contact Electricity Provider.
Typical repair cost £100-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Potterton models that show the Lights: Flash Off Flash fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Potterton Lights: Flash Off Flash fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026