High
E03 818 on Ariston Genus One 24

Your boiler has detected an issue with the sensors that ensure air is flowing correctly through the system, causing it to shut down for safety reasons.

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

Air pressure switch

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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