User:HVAC San Jose

The blower door is in no way and actual door, but rather it is a diagnostic tool that is used to pressurize and depressurize a home in order to track air flow in an attempt to measure the amount of leaks. The collected data is then recorded on a computer that issues a report of the findings to either the homeowner or the builder. In some cases, a smoke puffer is also used to help further locate air leaks. These tests allow people to get a clear image of exactly how and where the air is traveling within a home.

The technology was first used in 1977 in Sweden. It was quite primitive in the earlier stages and used little more than a window mounted blower fan. The main purpose of the test at this time was to determine the toughness of building envelopes. The blower door continued to evolve and in 1979, Harrje, Dutt, and Beya used the technology to identify hidden bypasses. This was done as a way to weatherize and retrofit older buildings. Over the course of time Harrje and Sonderegger further improved upon the device to make it closer to what it is today: "an instrumented audit and automated optimization system".

Today, the blower fan uses a specialized calibrated variable speed fan that has been installed in a door panel system to measure total air flow and tightness. A pressure sensing gauge is then used to measure the air pressure that was produced by the current of the fan. The entire device is fitted into an external doorway of a home and air is pumped both inside and out to create pressure. The pressure then forces the air through all cracks, gaps, and other sources of leakage. The fewer leaks a building has, the less air will be required from the blower door to cause a change in pressure.

So, why should you consider hiring a professional energy auditor to perform this test? There are really four main reasons: 1.	To reduce the total amount of energy wasted each year due to leaks; 2.	To reduce or eliminate drafts that allow cold air in, warm air out, and vice versa; 3.	To eliminate moisture and condensation issues; 4.	To maintain healthy home air quality that is not tainted with pollution and other impurities.

It is important to note that every house leaks and that it is not always entirely a bad thing. The amount of leakage within a home is called the infiltration rate. Problems arise when this rate is out of whack. For example, houses that have too high of an infiltration rate (those that leak too much), bring in high amounts of external air that can cause humid or dry conditions, mold, dust, and even carbon monoxide to accumulate. Houses that have too low of an infiltration rate (those that leak too little) can also be unhealthy because this can cause humidity levels to rise leading to high levels of dust mites and mold, as well as elevated carbon dioxide levels. Low infiltration can also cause combustion appliances to produce high amounts of carbon monoxide that can enter living areas.

The only way to know if your ratio is awry is to have the blower door test completed. This simple test can provide you with data that can drastically improve your health, your home, and even your financial situation.

For more great tips please visit your Sunnyvale Home energy efficient experts.