High
Safety overheat device tripped on Worcester Bosch Greenstar i

Your boiler has sensed that the water inside has become dangerously hot and has shut itself down as a safety precaution.

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

All air vented. Water pressure above minimum. Leaks or blockage. Condition and attachment of CH flow sensor. Pump and associated wiring/connections. Connections and wiring to overheat thermostat devices. Otherwise replace control board.

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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