Emergency
E52 on Biasi Rinnova Adaptive Combi

Your boiler has detected that exhaust fumes are not escaping correctly through the flue pipe or are being sucked back into the unit, causing it to shut down for safety.

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

Flue gas obstruction error (recirculation or flue obstruction)

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

E03View →E23View →

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