FLOWTECH Side Bypass Terminal Units handles constant supply of primary air through its inlet and uses a diverting damper to bypass part of supply air into the plenum return. The damper is directly controlled by room thermostat in the occupied space to provide the volume of air required to meet the thermal demand. The pressure requirement through the supply air path to the conditioned space is set with an inlet balancing damper. A second manual balancing damper in the bypass is field adjusted to match the resistance in the discharge duct in order to maintain minimum airflow to the space. Although variable air volume to the space in operation varies, the total airflow of the fan remains constant, so the fan power associated energy cost is not reduced. Therefore, bypass units are not energy efficient.