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What is the principal benefit of using a DOAS system?
What Are the Benefits of a DOAS? They improve indoor air quality by removing contaminants from outdoor air before channeling it into a building. DOAS units are effective dehumidifiers, and they help prevent moisture-related problems like sick building syndrome and mold growth.
What is a DOAS air handler?
A dedicated outdoor air system (DOAS) is a type of heating, ventilation and air-conditioning (HVAC) system that consists of two parallel systems: a dedicated system for delivering outdoor air ventilation that handles both the latent and sensible loads of conditioning the ventilation air, and a parallel system to handle …
What is the purpose of a DOAS?
The goal is to deliver precise amounts of ventilation to spaces regardless of load size, and do it cost-effectively. Known specifically as a Dedicated Outside Air System, or DOAS HVAC unit, the outdoor air is conditioned separately from the air that controls the building’s space temperature (dry bulb).
How can DOAS save energy when used in conjunction with a central VAV system?
A dedicated outdoor air system (DOAS) supplies outside air to the terminal units in the building separately from the main supply air. This strategy allows for better humidity control, more precise air delivery, and decreased energy consumption.
Is an ERV a DOAS?
A Dedicated Outdoor Air System (DOAS) with a high efficiency Energy Recovery Ventilator (ERV) is an alternative ventilation system design that can significantly reduce a building’s heating and cooling loads and provide controlled and conditioned ventilation that improves indoor air quality and occupant health, while …
How much does a DOAS unit cost?
| Cost item | Unit cost | Cost savings |
|---|---|---|
| Ductwork | $1/sq-ft DOAS, $4/sq-ft VAV | $558,000 |
| AHU | $2/cfm VAV $4/cfm DOAS | $170,000 |
| Electrical Serv. | $50/kW | $12,400 |
| Facade/partitions | $35/ ft 2 of facade | $150,780 |
Does a DOAS dehumidify?
A DOAS unit can also provide the dehumidified air directly to spaces at 55°F where it will offset some of the sensible load of the local HVAC unit. It is this technique that differentiates it from conventional HVAC systems. This configuration will cool and dehumidify air in the summer and heat or cool it in the winter.
What are the advantages of variable air volume air conditioning system?
The advantages of VAV systems over constant-volume systems include more precise temperature control, reduced compressor wear, lower energy consumption by system fans, less fan noise, and additional passive dehumidification.
Why is VAV system is efficient?
VAV systems are very cost effective from a chilled-water and heating-water-pumping perspective. Because the unit transfers heat to the space using forced convection, the coil heat transfer area required is reduced as compared to a chilled beam.