The National Air Duct Cleaners Association (NADCA); also known as the HVAC Inspection, Cleaning, and Restoration Association; today announces the publication of a white paper on methods of inspecting ...

To fully understand how to install a high-velocity HVAC system, one must know what it is and what it does. Basically, it is a small duct, high-velocity airflow, heating and cooling system designed to ...

While exposed ceilings in office interiors lend a spacious, open feel, this trendy architectural feature has created a new challenge: finding a viable return air path. Plenum ceilings use the area ...

Article 725 covers remote-control, signaling, and power-limited circuits that are not an integral part of a device or appliance. The correct answer is: a) CL2P and CL3P Article 725 covers ...