Medium
Pump runs on Alpha CD28

Your boiler's water pump is running constantly, which often indicates the system is failing to detect that it has successfully reached the required temperature or is struggling to circulate water properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Follow section 'B' 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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