All Mill heaters from the 2013 season onwards have a lightning symbol on the heater’s display that indicates whether the heater is actively heating or not. If the lightning symbol is lit, the heater should be heating.
If the heater is not heating even though the lightning symbol is lit, it could indicate that something is wrong with your Mill heater. To test if the heater is defective, please do the following:
Reset your heater to factory settings.
Set the heater to the maximum temperature (35 degrees Celsius).
Within a couple of minutes, the heater should start heating.
If the heater does not heat, please contact your retailer. Bring your heater and your receipt with you to the retailer, and they will assist you further with your case. Alternatively, you can contact Mill support.