Alpha E20 Fault Code
The Alpha E20 fault code means: your boiler has detected a flame when it shouldn't be there, which has triggered a safety shutdown to prevent any risk.. It appears on 1 Alpha model in our database.
Technical description: False flame detection
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Alpha models that show the E20 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Alpha E20 fault code information on this page is sourced and cross-checked against the official Alpha service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026