Medium
UU/5 on Ariston Genus 24 MFFI

Your boiler is struggling to accurately measure or control the temperature of the hot water flowing from your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Domestic hot water output temperature (C°)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

A33View →

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