RP-173 -- Method of Evaluation Based on the Operating Characteristics of Air-To-Air Heat Exchangers: Plate, Heat Pipe, Run PDF

This paper describes and discusses the principles, advantages, and disadvantages of several types of air-to-air energy recovery devices including the open and closed run-around systems, the heat pipe exchanger, the thermal wheel, and the plate exchanger. Emphasis is placed on the potential energy savings in heating and cooling equipment and fuel costs by recovering energy from exhaust air before it is thrown away. Results indicate annual energy savings up to 23% with even larger savings in the size of the heating and cooling equipment. As expected, greatest savings occur when large amounts of outside air are required for ventilation.