12 Emergency

Potterton 12 Fault Code

The Potterton 12 fault code means: your boiler is struggling to burn fuel cleanly, which could be creating harmful fumes inside your home.. It appears on 1 Potterton model in our database.

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description: Burner Runs But Smoke, and or Smell, and or Pulsation - Defective nozzle
Typical repair cost £150-300 (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 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 27 April 2026