Outdoor air dehumidification systems have gained prevalence as more commercial buildings are properly sealed for energy efficiency and as local and national building codes change to capitalize on these energy savings. Ventilation and odor removal are among the reasons to push existing air out of space, and this requires 100% outdoor air intake to make up for this exhaustion of indoor air. Referred to as make-up air, this fresh air intake is inevitable and its dehumidification is essential for maintaining ideal indoor air quality, especially in moist humid climates. It is important to remove the excess moisture from outdoor air before it enters the building so the indoor HVAC system does not have to deal with this added moisture load.
Finding a 100% outdoor air dehumidification system is often not difficult, but finding one with the correct size and specs for your application may be the challenge. DCA builds a full line of 100% outdoor air units ranging from small 1.5-ton units up to 30.0 tons with 200 to 7000 CFMs. Our smaller 200 to 1200 CFM units may be the perfect solution for that office renovation project that you may be bidding.
Enthalpy Control
As the most common metric used in 100% outdoor air dehumidifiers, enthalpy control measures the total energy in the intake air. The right level of enthalpy depends on the level required by the space. An outdoor air dehumidifier that relies on enthalpy control is designed to remove moisture from the air while running at a lower flow rate than that of standard dehumidifiers. The outdoor air dehumidifier can also supply air at a broad range of temperature options, including neutral temperatures with the addition of the appropriate dehumidifier options.
Practical Benefits of Outdoor Dehumidifiers
Outdoor dehumidifiers provide several benefits in practical applications. To supply high-occupancy spaces like schools or office buildings with fresh air, 100% outdoor air dehumidifiers can pretreat outdoor air before it reaches the building’s air handling unit (AHU). This means the main AHU can be smaller, as it won’t need to manage additional loading of outdoor air. The AHU is the right size for managing the building’s own internal load, while the dehumidifier manages outdoor air.
Indoor pool rooms and other high-humidity indoor environments also benefit from 100% outdoor air dehumidifier solutions, which help manage make-up air from outside. When used with an internal re-circulating dehumidifier that removes moisture from the evaporating pool water, the 100% outdoor air dehumidifier can be adjusted as the seasons change, saving energy costs and consumption.
Indoor locations that benefit from air dehumidifiers for outdoor environments include:
- Large office spaces
- Educational institutions
- Lobbies and corridors of hotel and motels with indoor pools and spas rooms
An advantage of outdoor dehumidifiers is that the systems do not considerably affect the temperature of the air supply or create increased heating or cooling load. The air dehumidification solution works alongside the facility’s HVAC or make-up air system to remove undesired humidity. This is illustrated in more detail in this case study.
Fixed Reheating vs. Variable Reheating
Dehumidifiers (with an optional remote condenser) and air conditioning reduce the air temperature before it is supplied to a facility. During cooler months, an auxiliary fixed reheating system can improve comfort in the facility by heating and controlling some moisture in the air, but it can also incur higher energy costs due to its limited control over temperature.
On the other hand, dehumidification systems that rely on variable reheating can remove moisture while raising the temperature of the air being supplied. A variable reheat air dehumidifier can provide considerable savings compared to a fixed reheat system because it is better able to control heating and humidity.
Equipped with a remote condenser, air dehumidifiers for outdoor environments can remove moisture from the air and supply air with a neutral temperature. When combined with a DOAS, one can see many benefits.
DCA Dehumidifiers Made in the USA
American craftsmen and women build DCA 100% outdoor air dehumidifiers in Cedarburg, Wisconsin. Not only are we experts in the field, but we also understand the local and national requirements with which your project must comply. In addition, our products comply with the Buy American Act, which may assist in winning local and federal contracts for your project. Dehumidifier Corporation of America is value-driven quality, built here.
For more information on our line of outdoor air dehumidification systems, contact our knowledgeable application team today.
