Medium
E04 on Ariston Genus 24 MFFI

Your boiler is struggling to accurately detect the temperature of the hot water because a sensor connection has failed or disconnected.

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 temperature probe in open circuit

Engineer required

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

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Related fault codes

E03View →E05View →

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