High
BURNER FAILS TO START on Worcester Bosch Greenstar Utility

Your boiler is failing to start because it isn't receiving a signal to fire up or has lost its electrical connection.

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

No power to boiler; Faulty boiler thermostat; Programmer open circuit; Faulty control box

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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