How much does it cost to fix Potterton error code Lights: On Flash Flash?

Typical repair cost for the Potterton Lights: On Flash Flash fault is £150-350 including labour.

Lights: On Flash Flash High

Potterton Lights: On Flash Flash Fault Code

Q: What does the Potterton Lights: On Flash Flash fault code mean?

Your boiler has detected that there is not enough water circulating inside it, which triggers a safety shutdown to prevent the internal components from overheating.

Also written as LIGHTSONFLASHFLASH — same fault.

The Potterton Lights: On Flash Flash fault code means: your boiler has detected that there is not enough water circulating inside it, which triggers a safety shutdown to prevent the internal components from overheating.. It appears on 3 Potterton models in our database.

Technical description: Dry-Fire. Go to Dry-Fire section of the fault finding instructions.

Typical repair cost £150-350 (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: On Flash Flash fault code

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

Source

Potterton Lights: On Flash 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 27 April 2026