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Tech Tips:

My goal in this tech tip is to help those who struggle to understand heat pumps get their heads around them as quickly as possible and understand some of the things a tech needs to know about them. The basic idea of a heat pump is to use the compression refrigeration cycle to move heat […]

Isolation Diagnosis

There are many great diagnostic tools available to the service technician today, but I haven't found a tool as versatile as the simple isolation diagnosis. There are many ways this concept can be applied, but let's start with some examples so that you get what I mean. Low Voltage Short Circuit Isolation Diagnosis You arrive […]

Michael Faraday: Patron Saint of HVAC Technicians

Who was Michael Faraday—besides the guy we named the capacitor after? Well, actually, we named the measure of capacitance after him (the farad), but let’s not get all caught up in semantics. Faraday was a scientist who lived from 1791 to 1867. He was an experimental scientist who had little to no formal education but […]

Blower Fan Watt Draw Considerations for ECMs

I'd like to give special thanks to Steve Rogers from TEC for helping write this tech tip and sharing some helpful visuals. Thanks, Steve! ACCA Standard 310 introduced a grading protocol for HVAC systems. While HVAC practitioners won’t be the ones carrying out the tasks laid out in Standard 310, energy raters will conduct them […]

Tool Selection: Electrical Meters

I'd like to give a special thanks to Tony Gonzalez from Fieldpiece for providing technical guidance about the SC680's power measurement capabilities, as well as VAC and AAC measurements on ECMs. We’ve talked through specifications, applications, and features for a few tools, but none of them have been quite as hardcore as electrical meters. Like […]

Understanding 240-Volt Circuits

It can be useful to think of a multimeter as a “voltage drop” tool. Bryan covers the concept here in an excellent class that I highly recommend. This concept was a big help to me as I began to truly learn how to use a multimeter. A meter reads the voltage differential between two points. […]

The Unexpected Result of Series Circuits

When I teach electrical basics, we do this exercise where we sit down and connect a 10-watt bulb to a power supply and through a switch. It's a SUPER SIMPLE circuit—the kind you might have learned about in a high school science class. But then I grab another 10-watt bulb and tell them to connect […]

Understanding Relays With the 90-340

Relays can be used for many different control applications, including controlling fans, blowers, other relays, or contactors, valves, dampers, pumps, and much more. A 90-340 is a very common, versatile relay that many techs have on their truck. So, we will use it as an example. A relay is just a remotely controlled switch that […]

What is a GFI?

First off, the correct acronym for a GFI (ground fault interrupter) is “GFCI” (ground fault circuit interrupter). The purpose is to act as a safety device to protect from electrical shock. GFCIs are important components of electrical safety. GFCIs can be built into outlets, circuit breakers, and even extension cords. We generally use them for […]

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Podcasts:

History of AWG – Short #186

In this short podcast, Bryan explains the history of AWG, or American wire gauge, which is the sizing system we use for conductors in the United States. Wires weren't standardized before the 18th century (1700s). As fencing, telegraph, and electrical wires started coming out, there was a need for a standardized system. In England, […]

Analog vs. Digital Sine – Short #179

In this short podcast, Bryan breaks down the differences between analog and digital sine waves. Analog readings deal with an unlimited number of values; they are very precise and can have any number of decimals. As a result, the alternating current (AC) analog sine readings have very smooth curves when we read them on […]

Wiring Refrigerated Cases w/ Nathan & Phil

Phil Barr and Nathan Orr join the podcast to talk about wiring refrigerated cases in commercial spaces, including convenience stores and supermarkets. Cases may be medium-temp (or high-temp, in some cases) or low-temp. Medium-temp cases can typically defrost on their own during the off cycle, and low-temp cases may have electric or hot-gas defrost […]

Grounding and Bonding Myths Podcast

In this podcast episode, Bryan talks about grounding and some common misunderstandings related to ground, neutral, ground rods, and lightning. The common phrase that “current goes to ground” is a myth. The transformer (or the power source) that feeds a building creates a potential difference in charges (voltage); current is the motion of electrons between […]

High Voltage A/C Electrical Class

This podcast is a high voltage A/C electrical class that Bryan gave to some of the Kalos apprentices. The high voltage journey begins with basic electrical theory. Basically, a difference in charge is needed for electrons to move and generate power. Motors, which are inductive loads, are the greatest users of power that we will […]

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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 essential episode, Bryan sits down with Jeff and Tom from Copeland to dive deep into the world of scroll compressors and the critical topic of refrigerant compatibility. As the HVAC industry navigates new refrigerant standards and regulations, understanding how compressors are specifically designed and optimized for different refrigerants has never been more important.

The conversation begins with a comprehensive overview of refrigerant classifications, focusing on the A1, A2L, and A3 categories that technicians are encountering in the field. Jeff and Tom dispel common misconceptions, particularly around A2L refrigerants and their relationship to propane (R-290), clarifying that A2L refrigerants like R-454B and R-32 do not contain propane despite widespread confusion in the industry. They explain how regulatory pressures around Global Warming Potential (GWP) limits are driving the transition to these new refrigerants, with targets under 700 GWP for air conditioning applications.

The technical discussion covers the fundamental operating principles of scroll compressors and why they’ve become the dominant technology in HVAC applications. With over 200 million scroll compressors sold by Copeland, the technology has proven its reliability and efficiency. However, the guests emphasize a crucial point that many in the industry overlook: each compressor is specifically optimized for particular refrigerants. This isn’t just about basic compatibility – it’s about precision engineering to meet efficiency requirements and ensure long-term reliability. The scroll geometry, oil viscosity, and internal components are all carefully matched to each refrigerant’s unique properties.

Safety takes center stage throughout the discussion, with both guests stressing that while A2L refrigerants are “mildly flammable,” they require heightened safety practices that were previously considered best practices but are now mandatory. This includes nitrogen purging during brazing, proper evacuation procedures, comprehensive leak testing, and thorough documentation. The conversation also touches on the practical challenges contractors have faced, including refrigerant availability issues, while maintaining the importance of following proper procedures regardless of supply chain difficulties.

Topics Covered:

Refrigerant Classifications: A1 (non-flammable), A2L (slightly flammable), and A3 (flammable) categories and their safety implications
Compressor Optimization: How scroll compressors are specifically engineered for each refrigerant, including R-454B and R-32 applications
New Compressor Naming Conventions: Introduction of “Y” series compressors for A2L and A3 refrigerants, replacing the traditional “Z” series
Oil Viscosity Requirements: Different POE oil specifications (32 vs 46 viscosity) for various refrigerants and temperature conditions
Safety Protocols: Enhanced safety requirements for A2L refrigerants, including mandatory nitrogen purging and leak testing procedures
Glide Characteristics: Understanding temperature glide in R-454B (2.4 degrees) versus single-component R-32
Refrigeration Applications: Multi-refrigerant capability in commercial refrigeration compressors and natural refrigerant trends
Service Compressor Strategy: LX series compressors designed to cover multiple R-410A applications for aftermarket needs
Regulatory Timeline: Upcoming January 1, 2026 GWP limits for supermarket refrigeration systems
Tools and Resources: Copeland Mobile app for compressor selection, cross-referencing, and technical specifications
Training Importance: Critical need for enhanced technician education and OEM-specific training programs

Visit the EPA’s website to stay up to date on the latest HFC phasedown rulings and information at https://www.epa.gov/climate-hfcs-reduction.

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Scroll Compressors & New Refrigerants w/ Copeland

09/11/2025

Bryan Orr

Leaky Ducts = Sweaty Houses – Short #256