Medium
EE 1100 on Ariston Microsystem 15

Your boiler has lost the connection to the temperature sensor that monitors your underfloor heating, so it has stopped that specific heating circuit for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Technical description

Under floor heating temperature probe in open circuit

Engineer required

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

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