High
Block 80 on Atag Q 30CR

Your boiler has automatically stopped heating because the exhaust gases getting rid of your smoke and fumes are currently too hot.

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

Maximum flue gas temperature has been exceeded (if present). The block will not be cancelled until the flue gas temperature has arrived below the temperature.

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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