Breathing Homes: Ventilation, Fans, and Air Filters in VS .NET

Generating QR Code 2d barcode in VS .NET Breathing Homes: Ventilation, Fans, and Air Filters

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Taking advantage of natural air movement Using fans to move air wisely Cleaning up the air you breathe

nless you live in a perfect climate where it s never too hot or too cold, heating and air conditioning make up the largest component of your power bill If you rely solely on your heater and your air conditioner to keep you comfortable, then you re missing a big opportunity for energy efficiency The key to comfort is air movement By moving air appropriately through your home, you can achieve a much higher level of comfort and save money by using your HVAC system less, particularly in the summer This chapter tells you how

A small amount of air movement increases convective cooling quite a bit, which is why people like fans blowing when it s hot in the summer A fan can make a room feel 5 F cooler, even though the temperature has not changed In the winter, winds make air seem much colder, an effect known as the wind chill factor People seek breezes in the summer and avoid it in the winter, not because air movement changes the actual temperature, but because it increases the rate of convective cooling (Refer to 7 for a discussion on how convection heating and cooling works) That s why ventilation is so important to your comfort

Each house has a natural ventilation scheme, which is influenced by the following factors: The prevailing winds, as determined by the weather patterns in the climate in which you live The chimney effect, which dictates that hot air naturally rises while cool air settles The vent patterns of your home, as determined by the location of windows, doors, vents, and other openings in your home Methods of heating and cooling that take advantage of these factors to increase energy efficiency are known as passive methods The most efficient ways to move air always complement the natural ventilation scheme rather than work against it By understanding your house s ventilation scheme, you can exploit the prevailing winds and the chimney effect and optimize air movement through your home s vents You can passively cool your house well enough to avoid using your air conditioner on all but the hottest days

Prevailing winds are the winds that are most common in your area Wind has both a speed and a direction, and both are important Some areas have very consistent prevailing winds, while other areas experience changes almost daily You probably already have a good idea what the prevailing winds are where you live, but you can refine your understanding by paying more attention In particular, how do the winds change over the course of a day Over the seasons (Typically, prevailing winds come from the southwest in the summer, and the northwest in the winter) Prevailing winds dictate the arrangement of fans and window openings that will work best in your house Basically, you want to create a situation in which you take most advantage of natural air movement as possible because this comes entirely free of charge Figure 13-1 shows a typical situation If all four windows are closed, there s no breeze in the house If only one of the windows is opened, there s very little air movement in the house because air can neither enter nor leave If only windows 2 and 4 are opened, there is very little air movement because the two open windows are at the same air pressure; the movement of the

breeze is precisely the same at each window However, if windows 1 and 3 are both open, a good breeze moves through the house, entering window 1 and exiting window 3 If all four windows are open, you ll get much the same breeze as you do when only 1 and 3 are open