Test, Adjust, Balance (TAB)
Test, Adjust, Balance are the three major steps used to achieve proper operation of HVAC systems. In general, the TAB specialist performs air and hydronic measurements on the HVAC system and adjusts the flow as required to achieve optimum performance of the building environmental equipment systems. A certified written report which summarizes equipment performance, as well as performance deficiencies, is provided upon completion of the testing.
Testing: The use of specialized and calibrated instruments to measure temperature, pressure, rotational speed, electrical characteristics, velocities, and air/water quantities are required for the evaluation of equipment and system performance.
Adjusting: Adjust is the final setting of balance. Devices such as dampers and valves, adjusting fan speeds and pump impeller size/speed, in addition to automatic control devices such as thermostats and pressure controllers to achieve optimum performance and efficiency during normal operation.
Balancing: Balancing is the methodical proportioning of air and hydronic flows through the system mains, branches, and terminal devices using acceptable procedures to achieve the specified airflow or hydronic flow within testing and design limitations.
Deficiency: Deficiency is considered any circumstance that adversely affects the specified balance of a device or system.