Medium
E08 on Ariston Ecosystem 27 RFFI

Your boiler has switched off because the safety sensor for your underfloor heating system has detected that the water temperature has become too high.

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 system thermostat shutdown (boiler operation resumes automatically when the thermostat contact closes on cooling)

From this model's manual
Verified against the Ariston Micro Condens System installation & service manual.
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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