High
Failure at point E on Worcester Bosch 24CDi BF

Your boiler is failing to light the burner for your heating, which means your radiators will not warm 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

Main burner does not ignite during Central Heating sequence. Includes checks for 240V supply at terminal X8, transformer voltage on driver board, and sensor resistance (1.5 to 25 kohms).

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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