High
AA0022 on Ariston Genus 24 MFFI

Your boiler is failing to ignite because it cannot detect that the water is warming up after a few attempts, meaning you currently have no heating or hot water.

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

After three attempts at ignition, no increase in DT was detected

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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