Low
d1 on Alpha Eco 11 13

Your boiler is displaying a real-time measurement of the flame signal, which is a status indication rather than a fault, meaning the system is currently monitoring its burner performance.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Flame signal mA x 10 (approx)

From this model's manual
Verified against the Alpha Eco installation & service manual, page 23.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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