Medium
7 02 on Ariston E-Combi One System

Your boiler is having trouble communicating with the temperature sensor for your secondary heating zone, which may prevent that part of your home from heating up properly.

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

Zone 2 return sensor defective

From this model's manual
Verified against the Ariston E Combi One 24 installation & service manual, page 39.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the control board loses communication with the sensor monitoring the water temperature for your second heating zone. This is usually caused by the internal sensor failing due to age or a loose electrical connection in the wiring harness between the sensor and the main board.

Engineer required

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

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