The indoor air quality - The reason for replacement of water-heating system by air-heating system

People nowadays spend 90 % of their time in closed spaces, so that they became almost prisoners of their own civilization. But it is necessary to let fresh air into working and dwelling places if we want to feel well and breathe air that is not of a decterious quality. The use of energy for hearing and/or cooling rises with the effectiveness of ventilation that connects the concentration of pollution in the waste air (in the space) and the concentration of the air-pollution in the zone of breathing. And that means that the air-quality and the use of energy conflict.