Ventilation of residential premises leads to significant heat losses, which account for up to 40% of the total amount of heat loss in the room. Installation of plastic windows helps to preserve heat, but critically reduces ventilation, which negatively affects both the health of people (allergies due to mould, lack of oxygen, fatigue, sleep disturbance, headaches) and the condition of the premises (increased humidity, fogging of windows, dampness, black mould and fungus on the walls). Ventilation is usually achieved by opening windows, but this does not solve all problems and in the cold season leads to discomfort and reduces energy efficiency. Our houses have become like thermoses: they are warm but uncomfortable. An air recuperator works by forcibly drawing warm exhaust air from the room to the outside and drawing cold fresh air from the outside into the room. The air flows are separated inside the working module and at the inlet and outlet without mixing with each other. By passing through the heat exchangers in the working module, the warm exhaust air transfers its heat to the cold supply air. The recuperator is an ideal solution for eliminating mould and humidity, as the ventilation system maintains a healthy indoor climate by improving air circulation and preventing the accumulation of moisture and the spread of mould.