Medium Warning
414 on Ariston Microsystem 15

Your boiler has lost communication with the temperature sensor responsible for the third heating zone in your home, meaning that specific area may not heat correctly.

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

Room sensor circuit open or short circuit zone 3

What causes this fault?

This fault occurs when the boiler loses its electrical connection to the thermostat or sensor that controls your third heating zone. The most common reason is a loose or damaged wire between the boiler and the sensor, or a technical failure within the sensor unit itself.

Engineer required

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

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Related fault codes

411View →412View →413View →

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