How much does it cost to fix Chaffoteaux error code 3-?

Typical repair cost for the Chaffoteaux 3- fault is £120-250 including labour.

3- High

Chaffoteaux 3- Fault Code

Q: What does the Chaffoteaux 3- fault code mean?

Your boiler has failed to ignite because it cannot detect a steady flow of gas, likely due to air being trapped in the supply line.

Also written as 3 — same fault.

The Chaffoteaux 3- fault code means: your boiler has failed to ignite because it cannot detect a steady flow of gas, likely due to air being trapped in the supply line.. It appears on 2 Chaffoteaux models in our database.

Technical description: red L.E.D. light on reset button - Purge the gas pipe and press RESET button

Typical repair cost £120-250 (including labour)

Engineer required

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

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Chaffoteaux models that show the 3- fault code

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

Source

Chaffoteaux 3- fault code information on this page is sourced and cross-checked against the official Chaffoteaux service / installation manuals for each affected model.

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