High
Lockout light (constant) on Worcester Bosch Greenstar 15sbi

Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent damage, while the pump keeps running to try and cool it back down.

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

Boiler Overheat - Boiler overheat thermostat trip. Pump run continuously.

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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