Medium
A13 on Ariston Micro Combi 27 MFFI

Your boiler is failing to register a signal from the wall-mounted thermostat that tells it when to turn the heating on.

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

External (Room) Thermostat

Engineer required

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

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