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

Typical repair cost for the Potterton On Off On fault is £120-250 including labour.

On Off On High

Potterton On Off On Fault Code

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

Your boiler has failed to light the flame properly and has shut itself down as a safety precaution while trying to start up.

Also written as ONOFFON — same fault.

The Potterton On Off On fault code means: your boiler has failed to light the flame properly and has shut itself down as a safety precaution while trying to start up.. It appears on 4 Potterton models in our database.

Technical description: Ignition Lockout - go to Ignition Lockout section of the fault finding instructions.

Typical repair cost £120-250 (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 On Off On fault code

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

Source

Potterton On Off 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