Love the article, it explained everything in plain language that I could easily understand..except for why you would put the window airconditoner in the "lung room". I'm currently building a grow room with 2 1000w lamps, and had my buy list ready for in/out, now I'm not too sure. I've changed my mind so many times while researching this the past 2 months. I want to do it right the first time lol. I live in a cold climate, so maybe it may still be best for me to vent from the outside, but it sure would be nice not to have to change your air cooling plans for the seasons. If anyone who has a sealed room in a climate like Michigan, please give me your input.