Design Guide for Dedicated Outdoor Air Systems
|Publication Date:||1 January 2017|
For the purposes of this book, all material is based on the following definition of a dedicated outdoor air system (DOAS):
A dedicated outdoor air system (DOAS) uses separate equipment to condition all of the outdoor air brought into a building for ventilation and delivers it to each occupied space, either directly or in conjunction with local or central HVAC units serving those same spaces. The local or central HVAC units are used to maintain space temperature.
As shown in Figure 1.1, outdoor air conditions can vary drastically from season to season, and even throughout the day. What doesn't change is that buildings need to be ventilated with fresh outdoor air. DOAS are designed to ensure that a building receives the required amount of outdoor air, delivered at conditions that ensure occupant comfort-regardless of what the weather is doing outdoors.