How much does it cost to fix Chaffoteaux error code E 20?

Typical repair cost for the Chaffoteaux E 20 fault is £150-250 including labour.

E 20 Emergency

Chaffoteaux E 20 Fault Code

Q: What does the Chaffoteaux E 20 fault code mean?

Your boiler has detected a flame even though it is telling the gas supply to stay off, which is a safety fault that prevents the system from running.

Also written as E20 — same fault.

The Chaffoteaux E 20 fault code means: your boiler has detected a flame even though it is telling the gas supply to stay off, which is a safety fault that prevents the system from running.. It appears on 3 Chaffoteaux models in our database.

Technical description: Flame detected with gas valve off

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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Chaffoteaux models that show the E 20 fault code

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

Source

Chaffoteaux E 20 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 31 August 2026