High
Failure at point C on Worcester Bosch 24CDi BF

Your boiler is not reacting when you turn on the heating, meaning the radiators will stay cold even though the power is on.

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

Central Heating Mode: DEMAND indicator does not illuminate. Includes checks for 240V supply at terminals X10, X4, and X3, and potential replacement of flowswitch or pump overrun thermostat.

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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Related fault codes

Failure at point AView →Failure at point BView →

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