Medium
A13 on Ariston Genus 24 MFFI

Your boiler is failing to talk to your room thermostat, meaning it doesn't know when to turn your heating on or off.

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

DIY fix possible

Check your room thermostat has fresh batteriesEnsure the thermostat display is on and showing the correct temperatureTurn the boiler off at the mains for 60 seconds and back on to reset the connection

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Related fault codes

A01View →A03View →

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