Engineered Systems Magazine

DOAS: Mitsubishi Electric

May 14, 2012

caleffiMitsubishi Electric CITY MULTI® DOAS is designed to provide energy-efficient ventilation.

Mitsubishi Electric Cooling & Heating (Mitsubishi Electric) now offers the CITY MULTI® VRF Dedicated Outdoor Air System (DOAS), which is a system designed to supply outdoor ventilation air to a building independent of the HVAC air distribution or conditioning system.

“The DOAS is unique because of its energy efficiency, in that it can use the heat recovery feature to provide ‘FREE’ reheat,” says Joe Bush, CITY MULTI Applications Manager, Mitsubishi Electric Cooling & Heating. “No other split-type dedicated outside air system offers the installation flexibility and performance of the CITY MULTI DOAS.”

The DOAS pre-conditions outside air for introduction into downstream HVAC units, lessening the load on HVAC systems. Because the HVAC systems have to work less to condition the air to a certain temperature when used in conjunction with the DOAS, end-users can save on utility costs. The DOAS connects to a Mitsubishi Electric VRF outdoor unit with INVERTER-driven technology to provide energy-efficient outside air by utilizing waste heat from cooling cycles to provide reheat capability without needing an additional or supplemental energy source.

 Available for use in new construction or retrofit commercial applications, the DOAS accepts 100 percent outside air at temperatures ranging from minus four degrees Fahrenheit WB up to 109degrees Fahrenheit WB, preconditioning up to 1,200 CFM of air for introduction into downstream HVAC units. With line lengths of up to 541 feet one way, the application range is virtually limitless.