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HVAC BALANCE Double-Duct Systems - Call us at (800) 217-8437Our techniques in balancing VAV systems is based on balancing procedures outlined in the AABC National Standards. We ensure the building will be clean and free of dirt and dust. We test and adjust each VAV box, diffuser, grille, and register to within +/- 10% of design requirements. Air Balancing is Testing, Adjusting, and Balancing commercial air conditioning and ventilation systems.There are not just a few words that describe it. Balancing first came in need in the early 80s when new and more advanced A/C systems were being installed. As these systems began to get more complex the need for balancing increased. A very expensive and complex system was not complete without an independent balance company doing the TAB work. We are mostly recognized for setting up the amount of airflow that would be distributed from each air diffuser. Fan tracking measures supply and return airflows. The return-fan capacity is controlled to maintain a constant difference between supply and return airflow. The method is appealing because it measures the quantities of interest more or less directly. As previously mentioned, the direct-measurement method does not always measure low air velocities accurately; however, fan tracking reduces this risk by measuring airflow at duct velocity. Nevertheless, the method has been criticized because inaccurate outside-air-quantity measurements are the result of the cumulative inaccuracy of two independent measurements (supply and return airflow). Additionally, the method applies only to systems that have return fans. The varying exposures of the rooms of a school or other building similarly occupied require that more heat shall be supplied to some than to others. Rooms that are on the south side of the building and exposed to the sun may perhaps be kept perfectly comfortable with a supply of heat that will maintain a temperature of only 50 or 60 degrees in rooms on the opposite side of the building which are exposed to high winds and shut off from the warmth of the sun. With a constant and equal air supply to each room it is evident that the temperature must be directly proportional to the cooling surfaces and exposure, and that no building of this character can be properly heated and ventilated if the temperature cannot be varied without affecting the air supply. There are two methods of overcoming this difficulty: The older arrangement consists in heating the air by means of a primary coil at or near the fan to about 60 degrees, or to the minimum temperature required within the building. From the coil it passes to the bases of the various flues and is there still further heated as required, by secondary or supplementary heaters placed at the base of each flue. Although the initial cost of installing a VAV system is a somewhat higher than a traditional constant air volume (CAV) system; due in part to special controllers used to control the fan speeds and the added complexity of the VAV terminal boxes, the money saved when these big fans are running below maximum speed quickly pays off. Building ventilation is the process of bringing outdoor air into a building, circulating it, and later purging it to the environment. The main purpose of ventilation is to provide acceptable indoor air quality by diluting and removing contaminants from the indoor air. Building ventilation is achieved by natural or mechanical means, or by a combination of the two. Heating, ventilating, and air-conditioning (HVAC systems) account for 39% of the energy used in commercial buildings in the United States. Consequently, almost any business or government agency has the potential to realize significant savings by improving its control of HVAC operations and improving the efficiency of the system it uses. Heating can be accomplished by heating the air within a space (e.g. supply air systems, perimeter fin-tube radiators), or by heating the occupants directly by radiation (e.g. floor/ceiling/wall radiation or radiant panels). |
