Low
Burner output modulates on Alpha CD28

Your boiler is automatically adjusting its power levels, which is a normal part of its operation rather than a functional breakdown.

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

Follow section 'G' fault finding

From this model's manual
Verified against the Alpha Cd28 Combi 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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