Definition for word: Blower Door

(aka "infiltrometer'). A large fan surrounded by a housing that is temporarily installed in an exterior doorway during an energy audit. The fan in the blower door assembly is normally used to depressurize or suck air out of a house so that technicians can measure air leakage and find leakage points.

Referrence from

A blower door is a diagnostic tool designed to measure the airtightness of buildings. and to help locate air leakage sites. A blower door consists of a calibrated fan for measuring an airflow rate, and a pressure-sensing device to measure the air pressure created by the fan flow. The combination of pressure and fan-flow measurements are used to determine the building airtightness. The airtightness of a building is useful knowledge when trying to increase energy conservation or decrease indoor air pollution, or control building pressures.

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