White Plains High School

12,000 sq. ft. for The B-Wing 
Installer: Daikin 
System: Air source heat pump, retrofit 

Source: HeatSmart Commercial Clean Heating & Cooling (A Program of Sustainable Westchester)

At White Plains High School, the B-Wing is one of two original structures on campus constructed in the 1950s. Exterior structural beams were a common architectural design method and a way of ensuring the integrity of the building. However, this original design posed challenges when it came time to update the HVAC systems. The exterior structural beams were blocking the free-air space for the new, more efficient compressorized unit ventilator designs, which required higher condenser airflow than older models. 

Daikin Applied unit ventilators, which come with factory-installed electronic expansion valves (EEVs), utilized remote Daikin VRV IV heat pump condensing units to eliminate the need for condenser airflow. The VRV condensers were placed outside on the ground level where there is ample space and airflow to reject heat in cooling mode. The unit ventilators were also able to use the existing hot water heating system during the cold New York winters. 

The design included demand control ventilation, a feature which increased operating efficiency and budgetary savings for the District. EEVs in the system modulate the precise amount of refrigerant to each zone, meeting the requested set point in a more efficient manner. The demand control ventilation feature is continuously monitoring CO2 levels in the classrooms and bringing in fresh air accordingly, optimizing the volume of outside air supplied to the classroom. The single air filter in each unit removes particulate from the outside air before it is conditioned and supplied to the classrooms. The students and faculty now enjoy individual zone control, lower sound levels with the absence of ductwork and better indoor air quality.