Medium
116 on Ariston Clas HE R

Your boiler has detected that the external thermostat connected to your underfloor heating system has triggered a safety shut-off or is disconnected, meaning the heating will not run until this is resolved.

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

floor thermostat contact open

From this model's manual
Verified against the Ariston Clas He R installation & service manual, page 34.
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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