Stones heat up with a moisture -proof heater. The furnace body has good thermal insulation, almost all the heat generation occurs through the stones. The power of the furnace depends on the size of the cabin of the sauna. For single cabins, furnaces with a capacity of 3.6 to 4.5 kW of a single -phase voltage 220 V are used. For heating large cabs, stoves with a capacity of 6 kW are used. The most widespread stoves of 6.6 kW. Such stoves are produced for both single -phase and three -phase networks. More powerful stoves are produced, as a rule, in a three -phase performance. So when installing a home sauna, you first need to decide what power the stove will be and then prepare the electrical wiring. If there is no possibility to provide the necessary electrical power, then the sauna will not work.