High
AA2222 on Ariston Genus 24 MFFI

Your boiler is struggling to register that you've turned on a hot water tap, so it isn't starting up to provide hot water or heating.

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

The flow switch does not open

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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Related fault codes

A01View →

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