How much does it cost to fix Potterton error code E16?

Typical repair cost for the Potterton E16 fault is £150-300 including labour.

E16 High

Potterton E16 Fault Code

Q: What does the Potterton E16 fault code mean?

Your boiler has detected that hot water is flowing in the wrong direction or the water returning to it is hotter than the water leaving it, causing the system to shut down for safety.

The Potterton E16 fault code means: your boiler has detected that hot water is flowing in the wrong direction or the water returning to it is hotter than the water leaving it, causing the system to shut down for safety.. It appears on 2 Potterton models in our database.

Technical description: Return temperature higher than flow temperature

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 E16 fault code

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

Source

Potterton E16 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