7 13 Medium

Ariston 7 13 Fault Code

Also written as 713 — same fault.

The Ariston 7 13 fault code means: your boiler is having trouble reading the water temperature for one of the specific heating zones in your home, which may cause that part of the system to stop working correctly.. It appears on 11 Ariston models in our database.

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: Return sensor defective (zone 3)

What causes the Ariston 7 13 fault?

This fault occurs when the sensor responsible for measuring the temperature of the water returning from your third heating zone fails or sends an incorrect signal to the main control board. The most common reason is a physical failure of the internal thermistor component or loose wiring connections that prevent the boiler from monitoring the system's heat levels accurately. In some cases, it can be caused by moisture ingress or a buildup of debris affecting the sensor's sensitivity.

Typical repair cost £120-220 (including labour)

Engineer required

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

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Ariston models that show the 7 13 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ariston 7 13 fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026