Medium
Blue light: On / Lockout: Off on Worcester Bosch Greenstar 25Si

Your boiler is working fine to heat your hot water, but it is failing to turn on when your radiators request heat.

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

Boiler not operating during central heating demand (HW ok)

Engineer required

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

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