Ariston Clas HE Evo fault codes
Built 2012–2019
Previous generation, still widely in service, and it does not share the One numbering. Confirmed against its own manual: it adds 102 for a pressure sensor error, its fan code is 604 where the One series uses 612, and its 610 is a thermofuse rather than the One's heat exchanger overheat.
Codes on the Clas HE Evo follow the same Ariston scheme as the rest of the range. Where a code behaves differently on this generation, the code page says so.
Ariston fault codes
Every published Ariston code. Open a code to see which models and years it applies to.
- 501No flame was detected during ignition and the appliance has locked out. Check the gas supply and the condensate pipe before booking anyone.Get it checked
- 108The heating circuit does not contain enough water to run safely. Refill through the filling loop to about 1.2 bar and the code clears.Usually simple to fix
- 101The heating circuit has overheated and the appliance has shut down. The usual reason is that water has stopped moving, not that it is firing too hard.Get it checked
- 103The appliance is reporting insufficient circulation — water is not moving through it fast enough. Worth acting on before it becomes an overheat.Get it checked
- 604Fan speed is outside the range the appliance expects, so it will not allow the burner to light. This one needs an engineer.Get it checked
- 303The main control board has reported an internal fault. It needs an engineer, and it is worth checking the electrical supply before assuming the board is dead.Get it checked
- 109System pressure has gone above 3 bar. Usually this means somebody overfilled it, or the expansion vessel has failed.Get it checked