High
Failure at point G on Worcester Bosch 24CDi BF

Your boiler is failing to turn down or shut off its flame as it gets hot, which may cause the system to overheat and shut down for safety.

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

Burner does not modulate or shut down correctly as system temperature rises. Involves checking Modureg voltage and overheat thermostat activation.

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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