Emergency
Group 2, 8 flashes on Worcester Bosch Greenstar CDi Compact

Your boiler has detected an internal overheating issue or a blocked exhaust and has shut itself off to prevent damage or safety hazards.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

MAX safety thermostat activated. Flue gas thermostat overheat or APS activated

Engineer required

This is a emergency 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

EAView →D1View →

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