Low
Neon B Illuminated continuously on Alpha CB28

Your boiler is operating normally and the main burner is successfully lit to provide your heating or hot water.

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

Indicates the burner is alight.

From this model's manual
Verified against the Alpha/Alpha Alpha Cb24 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.

Engineer required

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

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All 8 fault codes on the CB28

Seeing a different code? Every code this model can display, in one place.

Neon A and B Flashing on and off alternativelyNeon A and B Flashing on and off at the same timeNeon A Flashing on and offNeon A Illuminated continuouslyNeon B Flashing (every 5 seconds)Neon B Flashing on and offNeon B Flashing very slowly (every 5 seconds)

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