12 Low

Potterton 12 Fault Code

The Potterton 12 fault code means: your boiler is simply performing a standard start-up sequence after being powered on and is operating normally.. It appears on 3 Potterton models in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Power On

DIY fix possible

Wait a few moments for the boiler to complete its self-testEnsure your thermostat or timer is calling for heatCheck that your gas supply is turned on

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Potterton models that show the 12 fault code

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

Source

Potterton 12 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