Medium
E08 on Ariston Genus 24 MFFI

Your boiler has lost the connection to the temperature sensor responsible for your underfloor heating, so it has stopped these heaters from working to prevent them from getting too hot.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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

What the manual says

Manufacturer manual

Under floor heating temperature probe in open circuit

From this model's manual
Verified against the Ariston Genus 24 Mffi Combi installation & service manual, page 47.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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