Effect of Bypass Control and Room Control Modes on Fan Energy Savings in a Heat Recovery Ventilation System

This study makes a novel attempt to analyse the effect of the bypass control and room control modes on ventilation energy saving in an 84 m(2) housing unit, which is the most frequently constructed unit-type among newly constructed apartment buildings in Korea. A heat recovery ventilation system was installed. The fan power consumption was measured via field experiments and analyses were made for potential energy savings. Experiments to confirm the power-saving effect owing to the application of the room control mode were performed under the heat recovery and bypass modes, using three air flow rates (0.5, 1.0 and 1.5 ACH). Additionally, the annual energy saving based on the application of the mixed mode (both bypass and room control modes) was calculated. The results obtained showed that when the mixed mode was employed, ventilation energy saving up to 10.76%-16.56%, which is greater than that obtained using only the heat recovery mode, was realized. Additionally, compared with all -room-ventilation, 26.69%-61.84% of ventilation energy could be saved if the mixed mode was applied only to the living room.