#a2l

Tech Tips:

This tech tip is an overview of the livestream by the same name, featuring HVAC School contributors Matt Bruner, Roman Baugh, and Adam Mufich, as well as special guests Don Gillis, Dr. Chuck Allgood, and Jason Obrzut. You can watch the full livestream HERE. These gents also gave the “Flammable Refrigerant Update” at the 2023 […]

Retrofitting Existing R-404A/R-507A Systems

This article was written by Don Gillis with Chemours. Thanks, Don! With the American Innovation Act (The AIM Act) in place and the reduction of the supply of hydrofluorocarbons (HFCs) in effect, the need to retrofit systems with lower global warming potential (GWP) refrigerants will become commonplace in the very near future. So, what does […]

Moving Forward with A2L refrigerants

This article about A2L refrigerants was written by Don Gillis with Chemours. Thanks, Don! HVACR service technicians find themselves at the forefront of the refrigerant transition in AC and commercial refrigeration. As hydrofluorocarbon (HFC) refrigerants with high-global warming potential (GWP) are being phased down, mildly flammable A2L refrigerants have been identified as potential lower-GWP alternatives. […]

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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 episode, Bryan talks about the situations when permits are not needed to install HVAC/R (or HVAC/R-related) components.

A few codes are universal in residential HVAC, including the International Residential Code (IRC) and the International Mechanical Code (IMC). The local municipality, also known as the authority having jurisdiction (AHJ), chooses which codes to adopt.

You do not need a permit to install plug-in, cord-connected appliances. However, you need UL-listed plugs. You can also replace plugs without needing a permit, but the ratings need to be correct. Anything less than 25v that doesn’t put out more than 50 watts of energy also doesn’t require a permit. Thermostats and many IAQ accessories, including UV lights, fall into this category.

Portable heating and ventilation appliances, including space heaters and portable cooling units or dehumidifiers, also don’t require permits. Evaporative or “swamp” coolers also don’t need a permit for installation. Self-contained units with 10 pounds or less of refrigerant and are actuated by motors with