36. High

Saunier Duval 36. Fault Code

Also written as 36 — same fault.

The Saunier Duval 36. fault code means: your boiler has stopped working because a sensor that measures the temperature of the water flowing into your radiators is providing an incorrect reading.. It appears on 4 Saunier Duval models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: The heating flow thermistor is too resistant.
Typical repair cost £120-220 (including labour)

Engineer required

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

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Saunier Duval models that show the 36. fault code

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

Source

Saunier Duval 36. 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