How much does it cost to fix Potterton error code 40?

Typical repair cost for the Potterton 40 fault is £150-300 including labour.

40 High

Potterton 40 Fault Code

Q: What does the Potterton 40 fault code mean?

Your boiler has detected a communication error between its internal electronic parts, meaning it has shut down as a precaution to prevent further issues.

The Potterton 40 fault code means: your boiler has detected a communication error between its internal electronic parts, meaning it has shut down as a precaution to prevent further issues.. It appears on 5 Potterton models in our database.

Technical description: Possible faulty components

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 40 fault code

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

Source

Potterton 40 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