Patent ID: 7334632

Claim:
A variable volumetric flow heat exchange system for a building air-to-air heat recovery system operable at first and second volumetric flow rate, the first volumetric flow rate being greater than the second volumetric flow rate, the building having a ventilation system including an air exhaust line for discharging stale air from inside the building and an air supply line for receiving fresh air from the outside the building, the heat recovery system including first and second flow passages and at least one ventilation system damper reciprocative between first and second positions, each of the flow passages including at least one heat exchanger, the first flow passage being in fluid communication with the ventilation system air exhaust line and the second flow passage being in fluid communication with the ventilation system air supply line when the ventilation system damper is in the first position, and the first flow passage being in fluid communication with the ventilation system air supply line and the second flow passage being in fluid communication with the ventilation system air exhaust line when the ventilation system damper is in the second position, each heat exchanger comprising: a plurality of heat exchange banks, including at least one continuous duty heat exchange bank, and at least one cyclic heat exchange bank; a damper assembly including at least one damper module having at least one damper reciprocative between open and closed positions, and a control system for moving the at least one heat exchanger damper to the closed position when the heat recovery system is operated at the second volumetric flow rate and for moving the heat exchanger damper to the open position when the heat recovery system is operated at the first volumetric flow rate.