It has been said that the air that the two of us breathe is vital to our survival, however, this is the case, but did you ever know about how central heating & cooling plus having pure air, then this is why it is entirely crucial to have the absolute best in heating & cooling plus one of those whole-home air cleaners. The air cleaner is not a must, that is if you have good air quality in your home & regularly change out the air filter of your central heating & cooling system. However, some areas of the world just have awful air quality in the atmosphere & have to get some sort of air cleaner in your home in order to make the air quality certainly good for you; In our local town, I am thankful because air cleaners are not certainly needed, however but, a neighbor of mine in another neighborhood does need to have some kind of air cleaner because the air quality in her neighborhood is absolutely the worst. She ended up getting one of those certainly expensive central heating & a/cs with a whole-home air purification program that is all controlled by the control unit on the wall. The control unit also controls her radiant radiant floors, which she had installed to substitute the regular central heating. It is a good thing that the air quality & weather conditions is not too awful where I live, because I would never be able to afford that brand new, current, top of the line & entirely high grade heating & cooling system.