High
Flame detection fault on Worcester Bosch Greenstar Utility

Your boiler is failing to light because the sensor that checks for a flame is unable to see one clearly.

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

Photocell filmed over (dirty); Photocell faulty; Control box faulty

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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Related fault codes

LockoutView →Ignition failureView →

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