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

Typical repair cost for the Potterton Flash On On fault is £250-400 including labour.

Flash On On High

Potterton Flash On On Fault Code

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

Your boiler's internal computer has developed a fault and is unable to operate, meaning the system will not provide any heating or hot water until a professional repairs it.

Also written as FLASHONON — same fault.

The Potterton Flash On On fault code means: your boiler's internal computer has developed a fault and is unable to operate, meaning the system will not provide any heating or hot water until a professional repairs it.. It appears on 4 Potterton models in our database.

Technical description: PCB Fault - Replace PCB.

Typical repair cost £250-400 (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 Flash On On fault code

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

Source

Potterton Flash On On 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