Chaffoteaux E 20 Fault Code
Also written as E20 — same fault.
The Chaffoteaux E 20 fault code means: your boiler has detected heat or fire inside when the gas supply should be turned off, which indicates a serious safety error.. It appears on 1 Chaffoteaux model in our database.
Technical description: Flame detected with gas valve off
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Chaffoteaux models that show the E 20 fault code
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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 27 April 2026