High
FAIL POINT K on Worcester Bosch 28 RSF

Your boiler is failing to light the gas burner because it is not receiving the correct signal to start the heating process.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Gas valve mode switch not set to 'NORM' or Water temperature low/gas pressure incorrect. Possible blue wire harness fault.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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