Harford Academy

The new Combination Harford Academy and Elementary School is a multi-story, approximately 220,000 square foot facility which includes a Public Day School and Elementary School. The Public Day School is a special needs program serving students 3 to 21 whose medical and educational needs cannot be met in a conventional school. This area of the building will house classrooms, a gymnasium, dining area and dedicated health / administration support spaces. The Elementary School portion is a conventional style school facility with classrooms, a gymnasium, dining area and admin spaces. The Public Day and Elementary programs will share the media center, kitchen, collaboration spaces and courtyards for secure outdoor learning and play.

The cooling source for the building will include two outdoor air cooled high efficiency chillers.  The outdoor machines will be located on the roof and will utilize screw compressors. The heating plant will consist of multiple high efficiency gas fired condensing boilers with stainless steel heat exchangers. The boiler arrangement will be sized for the total heating load as well as to provide N+1 boiler capacity.  Combustion and exhaust air will be direct vented to the exterior.  Heating water supply temperatures will be in the range of 120 – 160 degrees F. Heating water will be provided to VAV terminal units, air handling unit preheat & reheat coils as well as miscellaneous heating equipment (i.e. unit heaters, cabinet heaters, etc.).

Four-pipe chilled and heating water will be circulated throughout the building to serve air handling equipment. Central station variable air volume (VAV) air handling units located in penthouses will condition the classroom and administrative spaces. Single duct VAV terminals with heating water coils will provide zone control for each classroom/office. Single zone chilled/heating water air handling units will be utilized to serve the large volume spaces (i.e. gymnasiums, cafeteria, etc.).

Due to the unique student population of the Public Day School, the design team worked closely with HCPS to implement several design features. One of these was redundancy in the heating and cooling systems. As mentioned above, the boilers are sized for N+1 capacity to maintain full heating capability if one boiler needed to be taken offline for maintenance. On the cooling side, redundant DX coils were provided in select air handling units to provide a backup source of cooling. HCPS also expressed a desire for all equipment requiring routine maintenance to be located in dedicated mechanical rooms / penthouses. This is especially critical in the public day school portion of the building to avoid maintenance staffing having to access equipment in areas where special needs students may be present.