Medium
Primary flow switch operated on Alpha 240E / 280E

Your boiler detects water movement even when it is not supposed to, which often means an internal valve is stuck or a sensor is misreading the flow.

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 'C' fault finding

From this model's manual
Verified against the Alpha 240e 280e 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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