Wood stoves during their operation have a flue gas temperature at the outlet of the order of 280-390 degrees, while the heat is released into the atmosphere. Heat exchangers increase the efficiency of the furnace and increase the uniformity of space heating. When using heat exchangers, the efficiency of the stove increases, ie less firewood will be used to heat the same volume of the room.
Installation of heat exchangers adds from 3 to 10 kW of thermal power. Thus, you can additionally heat from 100 to 250 cubic meters of space on the same amount of firewood used.