Patent ID: 6889750

Claim:
A defrostable ventilation apparatus, for exchanging air between the interior and exterior of a building, for transferring water moisture and sensible beat between exhaust air taken from the building and fresh air taken from the exterior ambient air for delivery to the building, and wherein, air from the interior of the building is used as defrost air to defrost the ventilation apparatus, said ventilation apparatus having fresh air path means having a fresh air intake side and a fresh air discharge side, exhaust air path means having an exhaust air intake side and an exhaust air discharge side, a rotary exchanger wheel for transfer of water moisture and sensible heat between said exhaust air and said fresh air, said rotary exchanger wheel being configured and rotatably disposed so as to define a first air stream path and a second air stream path, said first air stream path defining a portion of said fresh air path means between the fresh air intake side and the fresh air discharge side thereof and said second air stream path defining a portion of said exhaust air path means between the exhaust air intake side and the exhaust air discharge side thereof, and a ventilation rotation component for inducing, during a ventilation cycle, ventilation rotation of said rotary exchanger wheel through said fresh air path means and said exhaust air path means, characterized in that said apparatus comprises defrost air path means for conveying defrost air to said fresh air intake side, said defrost air path means being configured to connect the exhaust an discharge side with the fresh air intake side for conveying defrost air to said fresh air intake side from said exhaust air discharge side, a damper component, said damper component being displaceable between a ventilation configuration for a ventilation cycle wherein said defrost air path means is closed off and said fresh air intake side and exhaust air discharge side are open, and a defrost configuration for a defrost cycle wherein said fresh air intake side and said exhaust air discharge side are closed off and said defrost air path means is open, and a defrost rotation component for inducing, during a defrost cycle, said rotary exchanger wheel to rotate at a defrost rotation speed of from 0 to 2 rpm through said fresh air path means and said exhaust air path means, and wherein during a ventilation cycle, when said damper component is in said ventilation configuration, fresh air is able to flow through said fresh air path means and exhaust air is able to flow through said exhaust air path means, and during a defrost cycle, when said damper component is in said defrost configuration, defrost air taken from the building, is able to circulate, for delivery back into the building, through said exhaust air intake side, through said second air stream path, then through said defrost air path means, through said first air stream path, and through said fresh air discharge side.