Dedicated outside air systems (DOAS) from the YORK® brand of Johnson Controls includes a range of 100% outside air units and mixed air units that help decrease indoor air pollution. With heat pump operation and water source operation, as well as a hot water heat option, the line delivers a number of heating and cooling combinations for greater application flexibility. The systems also feature an internal energy recovery wheel that pre-conditions outside air and reduces heating and cooling loads by transferring energy between the exhaust airstreams.
“Handling up to 20,000 cfm of air and providing as much as 70 tons of cooling capacity, the new YORK DOAS meets ASHRAE requirements for fresh air and energy efficiency, and addresses the needs of building owners and consulting engineers,” said John Tuleya, product manager, Applied DX products at Johnson Controls. “The system controls supply air to room neutral, ensures precise unit cfm delivery, and continuously conditions up to 100% of outside air. It also features an energy recovery wheel for greater energy efficiency.”
On average, we breathe in 3,400 gallons of air each day. Ambient indoor air pollution is a problem, affecting health and productivity in the workplace. Bringing in fresh, outside air is critical to maintaining indoor air quality. These DOAS units bring clean, dehumidified outside air into your office or workspace in all weather and climate conditions. This fresh, outside air helps to maintain air indoor quality and meet requirements for fresh air and energy efficiency while tackling the problem of indoor air pollution.
The DOAS heating system is designed to handle extreme weather conditions as well as spring time light-load days and can provide 100°F rise with turn down as low as 10% with gas control. In addition, from 55°F through 115°F the mechanical cooling system operates to properly condition the air, meeting the needs of a variety of applications. The unit features an independent reheat system for stable, predictable year-round performance. Its digital capacity control reliably maintains consistent 52°F to 55°F discharge air temperature during spring, summer, and fall seasons.
The DOAS line offers air or water cooled units in various configurations, ranging from cooling only to heat pump. A full selection of factory-installed options adds to system flexibility, including:
- Modulating or staged gas heat, modulating electric heat, or hydronic heat options to meet outside air heating requirements.
- Six row evaporator coil for maximum capacity and moisture removal
- On/off or modulating hot gas reheat to condition air to a neutral discharge temperature and accurate humidity control
- BAS connectivity, thanks to the native BACnet control system, which has been designed specifically for integration with multiple BAS via BACnet, Modbus, LonWorks, and N2 protocols.
Often paired with another heating, ventilation, and air-conditioning (HVAC) system, a YORK DOAS can operate in combination with a separate sensible cooling system for a bundled solution that satisfies the entire building load, sensible and latent. Paired system options include rooftop and self-contained units, chillers, water-source heat pumps, variable-air volume terminals, and variable refrigerant flow systems.