How much does it cost to fix Saunier Duval error code 04?

Typical repair cost for the Saunier Duval 04 fault is £100-280 including labour.

04 High

Saunier Duval 04 Fault Code

Q: What does the Saunier Duval 04 fault code mean?

Your boiler is failing to light the gas or cannot tell that the flame has successfully ignited, meaning it won't be able to provide heating or hot water.

The Saunier Duval 04 fault code means: your boiler is failing to light the gas or cannot tell that the flame has successfully ignited, meaning it won't be able to provide heating or hot water.. It appears on 8 Saunier Duval models in our database.

Technical description: Ignition fault -flame detection

Typical repair cost £100-280 (including labour)

DIY fix possible

Check if your home gas supply is active by testing another gas appliance like a hob.Inspect the condensate pipe (plastic pipe leadings outdoors) to ensure it isn't frozen or blocked.Try to reset the boiler by turning the main dial to the reset position for five seconds and then back to the heater symbol.

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Saunier Duval models that show the 04 fault code

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

Source

Saunier Duval 04 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