Because a DOAS system pre-treats the ventilation air, it allows a building design that addresses the ASHRAE 62 outside air requirements, while maintaining proper equipment sizing for space conditioning. This design provides superior occupant comfort and reduces energy costs, especially when combined with an optional enthalpy wheel.

The ClimateMaster DOAS unit uses a unique method of heating 100% outdoor winter air without the need for a separate auxiliary heat source such as gas or electric resistance in most cases. The DOAS unit is effective down to 15°F [-9°C] winter design temperature. With an optional enthalpy wheel, the system is effective down to -10°F [-23°C]. In summer, the refrigerant circuit with modulating reheat and hot gas bypass provides precise leaving air dew point control. Leaving air temperature and dew point at part load conditions are controlled just as precisely with onboard microprocessor controls.

The Tranquility OA series (HFC-410A) is available in 3 through 100 tons [10.6 to 351.7 kW] in horizontal and rooftop configurations, and 4 through 30 tons [14.1 to 105.5 kW] in vertical configurations. An optional enthalpy wheel is available for horizontal and rooftop units. Sizing software, which can be downloaded, simplifies selecting the DOAS units.