Medium Lockout
7 01 on Ariston E-Combi One

Your boiler is struggling to read the temperature for a secondary heating zone, meaning that specific part of your home may not heat up correctly.

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.

Technical description

Zone 2 outgoing sensor defective

What causes this fault?

This fault occurs when the internal sensor responsible for monitoring the temperature of the water leaving the boiler for your central heating stops sending a reliable signal. The most common reason is that the sensor has developed an electrical fault or has been damaged by wear and tear, meaning the boiler can no longer safely regulate your heating. In some cases, loose or damaged wiring between this sensor and the main control board can also trigger the error.

Engineer required

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

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