Barometric damper with magnetic latch

A method of using a barometric damper for a structure that allows communication between a high pressure region and a low pressure region, the damper having an open position, a closed position, and a position wherein a damper blade is freely movable in response to barometric pressure changes on opposite sides of the blade, said method comprising:

• selecting an open position for the blade when communication is desired between the high pressure region and the low pressure region;
• selecting a closed position for the blade when communication between the high pressure region and the low pressure region is to be prevented;
• and
• selecting a position that allows the blade to move freely in response to barometric pressure changes when the damper is desired to operate to equalize the pressure between the high pressure region and the low pressure region.

A barometric damper for a structure comprising:

• a housing adapted to be coupled with the structure, said housing defining an opening that allows spatial communication between a high pressure region and a low pressure region;
• a damper blade movably coupled with said housing, said blade being movable between an open position wherein the blade accommodates air passage through said opening, and a closed position wherein the flow of air through said opening is substantially precluded;
• and
• a lever movably coupled with said housing and having a contacting means for contacting said lever with said blade, said lever being movable between a first position wherein said lever accommodates free movement of said blade in response to barometric pressure changes on opposite sides of said blade, a second position wherein said contacting means contacts said blade to hold said blade in its closed position, and a third position wherein said contacting means holds said blade in its open position.