AAON chillers are engineered for performance and serviceability. Variable capacity compressors and high efficiency air-cooled and evaporative-cooled condensing are available to maximize performance. Factory engineered and installed chilled water pumping packages complete the system. Factory-installed controls arrive ready for operation. AAON chiller outdoor mechanical rooms feature weatherproof double wall rigid polyurethane foam panel construction with lighted walk-in service compartments to allow maximum accessibility while installing and maintaining the equipment. A boiler and boiler pumping package can also be factory-installed in the outdoor mechanical room.