Sauna stove with net casing

Our enterprise has produced stoves with net-casing since the year of 2006.
Correctly chosen sauna stove (according to the size of sauna bench and other parameters, without water tank) can be heated within approx. 60-90 min. (in case of water tank heating requires more time, depending on its size). This time is enough to heat sauna bench until 100 degrees. Fresh air intake and used air exit are also relevant.