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Tech Tips:

I was talking about dry contacts with one of my techs, and he looked at me like I had three heads—and one of them was on fire. So, I figured it would be good to cover the difference between wet and dry contacts in a tech tip. Basically, “dry” contacts are switches with no shared […]

Motor Speed – The Basics

How does a typical single phase motor know how fast to run? Typical induction motors are dependent of the electrical cycle rate of the entering power (measured in hertz) for their speed. Our power in the US makes one complete rotation from positive electrical peak to positive peak 60 times per second or 60hz (50hz […]

Ohms/Continuity Basics

Some quick basics – An ohmmeter is used to measure the resistance to electrical flow between two points. The ohmmeter is most commonly used to check continuity. Continuity is not a “measurement” as much as it is a yes/no statement. To say there is continuity is to say that there is a good electrical path […]

What Makes an Autotransformer Different?

The definition of a transformer is a device that changes the voltages in an alternating current circuit. You may have heard of an autotransformer or a buck-boost transformer, and these terms are usually used for the same type of device; they just highlight different aspects. A transformer does not need to be a buck-boost to […]

Lockout/Tagout Basics

DISCLAIMER: HVAC School is NOT an official OSHA safety training resource! Although we provide safety tips in good faith, our website is not a substitute for safety training from an authorized OSHA training source. Locking out and tagging equipment is one of the most basic safety procedures in general industry and maintenance work, especially in […]

Crankcase Heaters and Single-Pole Contactors

We keep two-pole, 40-amp 24v coil contactors on all of our vans. They are versatile and reliable, and you can replace most residential A/C contactors with them. There are a few things to watch for, though, especially when you have a crankcase heater. Many brands power the crankcase heater constantly and shut it on and […]

An Electric Heat Mistake

I started working as a tech when I was 17 years old, fresh out of trade school. My first winter out on my own, I went to a service call in an older part of Orlando, a part of town I had never worked in before. It was an especially cold winter that year, and […]

Strip Control Wires Properly

Erich Vinson is a tech from Colorado and one of the most entertaining people I interact with online. He wrote this quick tech tip on stripping back the outer jacket properly on control wires, and it happens to also be something I preach. Thanks, Erich. In the first picture (above), you can see what happens […]

Grounding and Bonding Myths

Grounding is an area of many myths and legends in both the electrical and HVAC fields. This is a short article, and we will briefly cover only a few common myths. For a more detailed explanation, I advise subscribing to Mike Holt's YouTube Channel HERE. Myth – Current Goes to Ground Actually, current (electrons) 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