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Overview Heating, ventilating and air-conditioning (HVAC*) systems can play several roles to reduce the environmental impact of buildings. The primary function of HVAC systems is to provide healthy and comfortable interior conditions for occupants.
Well-designed, efficient systems do this with minimal non-renewable energy as well as low air and water pollutant emissions. You can rely on Emerson and our broad capabilities in products and services to develop unique, high-value integrated solutions.
* HVAC is sometimes referred to as "climate control" is particularly important in the design of medium to large industrial and office buildings such as sky scrapers and in marine environments such as aquariums, where humidity and temperature must all be closely regulated while maintaining safe and healthy conditions. Refrigeration is sometimes added to the field's abbreviation as HVACR.
Fans Exhaust Fans
Exhaust fans are designed for easy and efficient installation for the ventilation. They are best used for the removal of smoke, heat or in areas like parking garages to vent out posionous gases like carbon dioxide. Where mositure is a concern they can also help reduce humidity that causes mildew. Exhaust fans come in open motors for efficient cool running and low energy consumption and with sealed or enclosed motors for high dirt and grease applications such as a commercial kitchen, mill or commercial laundry. Condenser Fans Condenser fans, either single or multiple units may be operated from one drive. The results of using variable speed includes: Energy reduction due to the fan affinity laws: The elimination of demand load penalties as related to the use of the VFD: Repeatable set point head pressure control also having energy reduction results: Ambient noise reduction due to the elimination of contactor “staging” on and off of the fans. Other benefits include the elimination of fan blade mechanical stress: Stress on the fan motor due to excessive cycling.
Pumps Chill Water Pumps
Chill water pumps move cold water from the chiller to the air handling units. Chilled water is used to cool and dehumidify air in mid- to large-size commercial, industrial, and institutional facilities. Conervesly hot water pumps move hot water and heat air in facilities.
Cooling Tower Cooling Towers
Cooling towers are evaporative coolers used for cooling water or other working medium to near the ambient wet-bulb air temperature. Cooling towers use evaporation of water to reject heat from processes such as cooling the circulating water used in oil refineries, chemical plants, power plants and building cooling, for example.
An HVAC cooling tower is a subcategory rejecting heat from a chiller. HVAC use of a cooling tower pairs the cooling tower with a water-cooled chiller or water-cooled condenser. Industrial cooling towers can be used to reject heat from various sources such as machinery or heated process material. The primary use of large, industrial cooling towers is to remove the heat absorbed in the circulating cooling water systems.
Fume Hoods Fume Hoods
Most fume hoods for industrial purposes are ducted. A large variety of ducted fume hoods exist. Air is removed from the workspace and dispersed into the atmosphere. The fume hood is only one piece of the ventilation system. To reduce ventilation costs, variable air volume systems are employed, which reduce the volume of the air exhausted as the fume hood sash is closed. This product is often enhanced by an automatic sash closing device, which will close the fume hood sash when the user leaves the fume hood face. The result is that the hoods are operating at the minimum exhaust volume all of the time that no one is actually working in front of them.
Stairwell Pressurization Stairwell Pressurization
Pressurization has been used for many years to prevent the spread of biological and chemical contaminants in many environments including hospitals and laboratories. The same process is used to control the spread of smoke in a building fire. A pressure difference across an opening can be used to prevent the movement of smoke from one side to the other. The high pressure side of the opening can be used as refuge from the smoke or in the case of stairwell an egress route. The pressure difference to prevent the migration of smoke can be as small as 2 PA (0.01 in water guage). Fires can increase pressure due to the buoyancy of hot gas. Building pressures can change due to changes in weather, wind, and doors being open or closed. Too much pressure across a stairwell door can prevent a door from being opened, too little allows for the introduction of smoke into the stairwell. To account for these variances and allow for a safe exit through a stairwell it is important that the pressure difference be closely maintained. Creating and maintaining functional stairwell pressurization can be difficult in tall stairwells with many doors. Pressurization air may have to be introduced and controlled at various points within the stairwell. Using variable speed drives and proper controls can make the control of pressure with a stairwell a much easier problem to solve.
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