Supermarkets present unique challenges for HVAC systems. First, a supermarket includes a variety of spaces which each have different temperature and humidity control requirements. Some examples include a grocery area, dairy and frozen foods area, bakery, deli, floral area, photo processing center, pharmacy, office space, and checkout stands.
Second, a supermarket is occupied for many hours of the day, almost everyday of the year, with occupancy levels varying throughout the day.
Third, the HVAC system must be sized to positively pressurize the building to prevent infiltration. If the building is not positively pressurized, the doors, which are constantly opening and closing, will permit infiltration of outside air, adding latent and sensible loads to the space.
Fourth, refrigeration and freezer systems in supermarkets reduce the sensible load, but not the latent load of the space. Thus, humidity control is often as important as temperature control in a supermarket.
AAON has experience in controlling a tight temperature and humidity of the space with variable capacity compressors, variable speed compressors and modulating hot gas reheat.