What to do if my Ariterm Biomatic+ 30 Boiler displays 'ALARM MAX THERMOSTAT'?
- DDaniel WilliamsNov 5, 2025
If the display shows 'ALARM MAX THERMOSTAT' or 'ALARM MAX THERMOSTAT ELECTRIC' and the over-temperature protection of the boiler has tripped, it could be due to several reasons. First, ensure the motor shaft rotates the auger and the external auger motor is working. If the motor doesn't rotate, plug the power cable directly into a mains socket using the provided cable; the motor's over-temperature protection might have tripped due to overheating, so let it cool down and check for blockages. Reset the boiler's over-temperature protection by pressing the RESET button, then switch the control unit OFF and back ON, also verifying the 3-phase current connection. Also, the flame guard and combustion head may be full of ash. Remove any ash, clean the combustion head, and wipe the flame guard. If ...






