High
Group 2, 6 flashes on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a failure in its internal safety checks during startup and has safely shut itself down to prevent any risk.

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.

What the manual says

Manufacturer manual

Sensor test failed. On power up all safety sensors are checked, the check failed.

From this model's manual
Verified against the Greenstar 27 30 RiCompact ErP installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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