High
278 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a failure during its internal safety startup check and will not fire up to prevent any potential risks.

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

Sensor test failed Reset button On power up all safety sensors are checked. Check has failed.

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

274View →276View →

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