Medium
B02 on Ariston Microsystem 15

Your boiler is struggling to communicate with your wall 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

Room Thermostat

DIY fix possible

Check if your thermostat batteries need replacingEnsure your thermostat is switched on and showing a displayTurn the boiler off and back on at the fused spur to reset the connection

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