Ariston TCS STATE Fault Code
Also written as TCSSTATE — same fault.
The Ariston TCS STATE fault code means: your boiler is currently in a normal waiting state because it has reached the required temperature and is managing its own internal heating cycle.. It appears on 1 Ariston model in our database.
Technical description: There is no demand of heat due to the internal regulations of the boiler
DIY fix possible
Check that your room thermostat or programmer is set to a high enough temperature to call for heatWait 5 to 10 minutes for the boiler to complete its anti-cycling periodEnsure your radiator valves are open if you are testing the central heating
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Gas Safe Register →Ariston models that show the TCS STATE fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ariston TCS STATE 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 27 April 2026