High
40-60-70 (ll-ll-ll) on Ariston Genus 30 Plus

Your boiler has detected that a safety switch is stuck in the wrong position, which prevents it from starting to avoid any risk of incorrect combustion.

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 off but air pressure switch fails to return to off position

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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