What is a heater in Techno Lit sauna stoves? How many stones to load? The bigger, the better?

Russian bath cannot be imagined without water vapor. Steam allows you to warm up not at 100C, but at 50C and do broom massages (it won’t work in a dry, not wet, steam room - the leaves from the broom will fly around). And the steam in the bath needs to be light - the water particles in the steam-air mixture should be as small as possible and tend to the size of the molecules.

In Techno Lit sauna stoves, the main heat accumulator is a heater - a steam generator with direct fire heating (as opposed to indirect, where the stone container is first heated, and then each subsequent stone transfers heat to another).

The steam in our stoves is obtained by supplying water to the heater, which is loaded with a relatively small amount of stones, and the heater itself is a steam generator, has a significant mass and is heated by direct contact with the fire. Different models have different designs, but the principle is the same: we heat the heater with a flame and pour water into it!