High
FAIL POINT L on Worcester Bosch 28 RSF

Your boiler's electronic command center has encountered a serious internal error and is unable to safely control the unit's operation.

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

Light indication during fault not covered by other details. Control board wet, damaged, or malfunctioning.

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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