Low
Neon D on Alpha Cd25

Your boiler is operating normally and is receiving a steady supply of electricity.

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

Illuminated continuously - Electricity supply to the boiler is on.

From this model's manual
Verified against the Alpha Cd25 Combi 2 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if your thermostat or programmer is set to call for heatEnsure the central heating selector switch is in the 'on' positionVerify that your hot water tap is open if you are testing for immediate output

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