BoilerFaultCodesWhat the manual says
Manufacturer manualRoom sensor circuit open or short circuit ZONA 1
From this model's manual
Verified against the Ariston E Combi One 24 installation & service manual, page 38.
What causes this fault?
This fault occurs when the connection between your boiler's internal computer and the main room thermostat is broken. The most common reason is a loose or damaged wire within the control circuit, or a component failure inside the thermostat itself that prevents it from sending signals to the boiler.
DIY fix possible
Check if your room thermostat or Clima Manager has run out of batteriesEnsure all wired connections to the thermostat are secure and haven't been knockedRestart the boiler using the Reset button to see if the communication error clears
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