How much does it cost to fix Saunier Duval error code E26?

Typical repair cost for the Saunier Duval E26 fault is £150-250 including labour.

E26 High

Saunier Duval E26 Fault Code

Q: What does the Saunier Duval E26 fault code mean?

Your boiler has detected that the water temperature is significantly different between the start and end of its heating circuit, which suggests the water is not circulating properly.

The Saunier Duval E26 fault code means: your boiler has detected that the water temperature is significantly different between the start and end of its heating circuit, which suggests the water is not circulating properly.. It appears on 2 Saunier Duval models in our database.

Technical description: Difference between flow and return thermistors too high

Typical repair cost £150-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Saunier Duval models that show the E26 fault code

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

Source

Saunier Duval E26 fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026