High
Failure at point B on Worcester Bosch 24CDi BF

Your boiler is struggling to keep its internal pilot light lit, which is preventing the main heating system from starting up.

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

Pilot flame does not remain established. Check if overheat thermostat has tripped, pilot flame height (18-20mm), pilot injector blockage, and thermocouple/gas valve connections.

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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