High
EE7744 on Ariston Genus 27

Your boiler has stopped working because one of its internal sensors is reporting an electrical fault and can no longer monitor the temperature of the water coming back from your radiators.

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

Heating return temperature probe in short circuit

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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