Air diffusers and air grilles are used to control and direct airflow in heating, ventilation, and air conditioning (HVAC) systems. Industrial diffusers (HVAC diffusers, diffuser dampers) are also used in industrial air-dispersion applications.
Product categories include two-way diffusers, four-way diffusers, and radial vane diffusers. With each type of product, a rugged metal frame surrounds an array of vanes or blades. These blades are positioned to achieve the most effective airflow for the application. Each blade is held in place by its own tensioning device. Diffusers with single-skin blades and airfoil blades are commonly available.
Air diffusers carry product specifications for the frame, blades, axles, hub, and mounting straps. The frame and blades are usually made of galvanized steel. The number of blades varies by model. One-piece radial vane diffusers have two axles, each of which is made of plated steel and welded at both ends. The hub and four to six mounting straps that come with each unit are also made of steel. White epoxy enamel is a common finish. Additional specifications for radial vane diffusers include maximum temperature, minimum size, maximum size, and duct dimension. The minimum and maximum sizes represent the inside diameter (ID). The duct dimension is the outside diameter (OD).
Air grilles are usually made of aluminum, bronze, steel, or stainless steel and then polished, anodized, or treated with enamel colors. There are many different types of HVAC grilles. Choices include perforated, bar, floor, and extruded. Custom plates, radiator covers, and mitered corners and access doors are also available. Perforated grilles, bar grilles, and floor grilles have specially-shaped openings to promote the flow of air. These shapes may resemble bricks, diamonds, bullets, or shells. Standard industrial grilles often feature slats instead. Products with an acoustically-transparent perforated liner and that use acoustical-grade fibrous media are designed for sound-control applications.
Suppliers of air diffusers and air grilles are located across North American and around the world. They often manufacture and/or distribute a range of HVAC products. Examples include air handlers, central air conditioning systems, dampers and louvers, energy recovery and heat recovery ventilators, evaporative coolers, fireplaces, heart pumps, and heating furnaces. Suppliers of diffuser and grilles may also provide HVAC chillers, HVAC ductwork, and specialty HVAC equipment; room air conditioners; and vents and venting systems.