Purpose — This procedure describes how to determine if airflow across the evaporator in a cooling system is adequate. For proper operation of a cooling…
Purpose – This procedure describes how to measure the temperature rise in fossil-fuel furnaces. Temperature rise is the difference between the return air temperature entering…
The rotating magnetic field of the resistance-start induction-run motor is produced by the out-of-phase currents in the run and start windings. Since the run winding…
Return air grilles should be selected for static pressures. These pressures will provide the required NC rating and conform to the return system performance characteristics.…
Terminal boxes can sometimes be located over noisy areas (corridors, toilet areas or machine equipment rooms), rather than over quiet areas. In quiet areas casing…
The spread of an unrestricted air stream is determined by the grille bar deflection. Grilles with vertical face bars at 0° deflection will have a…
High velocities in the duct or diffuser typically generate air noise. The flow turbulence in the duct and the excessive pressure reductions in the duct…
Product research in controlling casing noise has developed a new method of reducing radiated noise. The technique is known as vortex shedding. When applied to…
Ventilating, air-conditioning, and heating ducts provide a path for fire and smoke, which can travel throughout a building. The ordinary types of dampers that are…