denis isaev from moscow used to feel either stuffy or cold in winter, depending on the frost. wind controlstem for 150,000 rubles. with three filters, a heating unit and a unit on the balcony, it became comfortable, however, then he checked and found out that there were pm2.5 particles from the smallest particles, the air was not purified, there were too many gaps in the connections, so i quickly found it through simple experiments with tape and a hairdryer, well, then i just used tape, foam plastic, all sorts of things... and then fiddling with tape, not very pleasant, by the way, this was a simplified and compact version with a pipe in one room , larger systems cost at least 250 thousand ; they are most often installed at the construction or renovation stage. we need to run a bunch of pipes along the ceiling and install a distribution pipe. there is an urgent need to make a ventilation system or even think about this issue, for people whose windows are crying, window frames are leaking, people who have mold in the corners. by the way, there are supply systems on the market that are simpl