High
Boiling on Worcester Bosch Utility

Your boiler is overheating because it cannot correctly measure or circulate the water inside it.

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

Faulty boiler thermostat; Short circuit boiler thermostat; Thermostat bulb not fully home in pocket; No primary water circulation

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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