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Tech Tips:

Fresh Air in Commercial Buildings: Economizer Sensors and Settings

This tech tip is based on a presentation by Joey Henderson, a veteran symposium speaker and excellent HVAC educator. You can learn more about Joey and the work he does at joejoehvac.com and his YouTube channel HERE. Simply put, indoor air is often nasty. People cough up and exhale germs, and cracks in the envelope […]

Ain’t No Fooling With Free Cooling (Tales of the Economizer)

This article was written by Gary McCreadie from “HVAC know it all.” You can learn more about Gary and his tips and growing community on Facebook and LinkedIn. What is an economizer? Simply put, it is a mechanical device designed to reduce energy consumption, whether it be fuel, electricity, or other. According to Wikipedia, the first […]

Ronald MUSE
#commercial hvac #Economizer #efficiency

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How to Evacuate an AC system, Full Vacuum Procedure

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HVAC School – For Techs, By Techs

Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

In this short podcast episode, Bryan explains how duct tape got its name and why it shouldn’t actually be used on ducts. Duct tape is a versatile home DIY-fix tool, but despite its name, it wasn’t initially made to seal ducts at all.

In 1943, we were in the thick of World War II, and ammo shipments were sealed with wax and paper tape. These were often not durable or difficult to open. Johnson & Johnson developed a tape with rubber adhesive on a cotton duck cloth backing (which was already widely used for military uniforms and tent fabrics). This new tape was nicknamed “duck” tape due to the material and its waterproof abilities (like the waterfowl). A woman named Vesta Stoudt informed President FDR about duct tape, and the War Production Board began using it in wartime supply packaging.

After the war, America had a housing boom in the 1950s, which included the demand for forced-air heating and cooling systems. Marketers thought the tape could seal the ducts in those homes, so they changed the color to match sheet metal and rebranded it as “duct tape.” In the 1960s, this tape was available in retail outlets with the “duct tape” branding.

Unfortunately, in tests by the Lawrence Berkeley National Lab, duct tape failed miserably at sealing the ducts because the rubber adhesive dries out under heat, and dust weakens the adhesive. As a result, many building codes ban duct tape on ducts (spearheaded by California). Instead, UL-listed foil tape and mastic are approved for sealing ducts. However, duct tape still became famous for its versatility as a patching material. It’s prevalent in pop culture and has been used in television shows and even in space.

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How Duct Tape Got Its Name (and Why It Shouldn’t Be on Ducts) – Short #264

11/04/2025

Bryan Orr

The Art of De-escalation

10/30/2025

Bryan Orr