High
40-60-80 (ll-ll-ll) on Ariston Genus 30 Plus

Your boiler is struggling to clear exhaust gases because it cannot confirm that the internal fan is moving air effectively, so it has shut down to keep you safe.

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

Fan on but does not activate 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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