If there was a heating system that worked properly and was adapted to the volume of the living room-kitchen, we could rate it as "Very good". According to the tech. The heater has a maximum output of 4000 W, which roughly corresponds to two large hotplates of 2000 W each. Much too little, in relation to the volume of the room. Due to the prevailing cold on the weekend of February 13-15, 2021, we only had 17°C in the living room. We were able to increase the temperature with 50 kg of firewood.