Medium
10 on Alpha 240XE

Your boiler is struggling to manage the water pressure inside its internal components, which may prevent your hot water from heating up properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

DHW expansion device (if fitted)

Engineer required

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

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