Medium
116 on Ariston Clas One

Your boiler has detected that a safety switch associated with your underfloor heating system has tripped or disconnected, causing the system to pause to prevent overheating.

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 One 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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