HVAC School - For Techs, By Techs

An R-454B Ramble w/ Elliot

· Summarized

Share this episode
Anyone with this link can open it.
Share Link
Start at 0:00

Key takeaways

  • R-454B systems require significantly longer stabilization times than R-410A, impacting technician practices.
  • Undercharging may be a beneficial strategy for technicians working with R-454B to avoid complications during service.
  • The reliability of new A2L components like sensors and dissipation boards may be concerning, introducing new potential failure points.
  • Industry politics and lobbying have played a significant role in the refrigerant options available, affecting service technicians.
  • Continuous education and observation through tools like thermal imaging can help technicians adapt to new refrigerant behaviors.

Summary

R-454B Charging Behavior

The discussion centered around the prolonged charging times of R-454B refrigerant, with technicians reporting stabilization periods of up to an hour, in contrast to the usual 15-20 minutes seen with R-410A. This slower stabilization leads to challenges with subcooling drift, complicating service calls and installations for technicians.

Field Charging Strategy

Technicians have begun to adopt strategies like intentional undercharging to mitigate issues with R-454B systems. Bryan and Elliot recommend relying more on line length specifications instead of fixed charge quantities to adapt to the unique characteristics of R-454B.

A2L Safety Components

The conversation highlighted concerns about reliability of A2L refrigerant sensors and dissipation boards. Though failure rates weren't drastically higher than other components, they introduced additional failure points which contractors need to be aware of.

Refrigerant Stratification Theory

Two main hypotheses were discussed regarding the delayed equilibrium behavior of R-454B: one involves density differences causing stratification in the condenser, while the other suggests that one component may act like a non-condensable, leading to operational inefficiencies.

Industry Politics

Bryan expressed frustrations with the political maneuvering behind refrigerant choices, particularly focusing on the contentious nature of R-454B's rollout and how it compares to R-32. The conversation underlined the impact of lobbying on refrigerant legislation.

Manufacturer Accountability

The duo critiqued manufacturers for lacking accountability during the rollout of new refrigerants. Problems like warranty support and the impact of untested components were emphasized as critical issues affecting contractors.

Future of HVAC

Looking ahead, Bryan and Elliot anticipated new technologies like heat recovery chillers and completely refrigerant-free systems. They discussed the importance of adapting to such innovations in the HVAC landscape.

Sponsors

  • Refrigeration Technologies · Featuring the new Viper wet rag heat shield, a flame-resistant welding pad suitable for wet or dry use.
  • TrutechTools · Providing a wide range of tools and exceptional customer service for 18 years, offering everything from power tools to blower doors.
  • Navac · Known for their cordless power tools used for bending and flaring copper quickly, offering a series of innovative tools.
  • Filtrete Air Filters · A leading air filter brand, though the segment humorously cautions listeners about the podcast content.

Show notes

In this raw and unfiltered episode, Bryan sits down with Elliot, a senior service tech and newly minted install supervisor, to discuss the realities of working with R-454B refrigerant in the field. What starts as a technical discussion about the new A2L refrigerant quickly evolves into a candid conversation about industry frustrations, manufacturer accountability, and the practical challenges technicians face with the latest refrigerant transition. With four years of hands-on experience, Elliot brings fresh perspectives on everything from charging procedures to equipment reliability issues.

The conversation takes an honest look at the R-454B rollout, which Bryan describes as a massive industry failure. Unlike typical manufacturer talking points, this episode dives into real problems technicians are experiencing: extended charging times, subcooling drift, and equipment component failures. Bryan and Elliot discuss how R-454B systems can take up to an hour to stabilize compared to the 15-20 minutes they were accustomed to with R-410A. This isn't just an inconvenience—it's affecting how technicians approach charging procedures and follow-up visits.

The episode also explores theoretical explanations for R-454B's unusual behavior. Bryan presents two hypotheses about why the refrigerant takes so long to reach equilibrium: either density differences between R-32 and R-1234yf are causing stratification in the condenser, or one component is settling at the top and acting like a non-condensable. While admitting he's "not a mathy details guy," Bryan encourages field technicians to investigate these phenomena using thermal imaging cameras and careful observation. This practical, boots-on-the-ground approach to understanding new technology exemplifies the podcast's commitment to real-world problem-solving.

Beyond technical discussions, the conversation touches on broader industry issues, including the politics behind refrigerant selection, manufacturer warranty support (or lack thereof), and the challenges faced by contractors trying to maintain fair pricing while dealing with new equipment failures. Bryan and Elliot also address the reliability concerns with new A2L safety components like dissipation boards and refrigerant sensors, noting that while failure rates aren't dramatically higher than other components, they represent additional potential failure points that weren't previously necessary.

Topics Covered

  • R-454B Charging Behavior: Extended stabilization times (up to 1 hour vs. 15-20 minutes for R-410A) and subcooling drift over time
  • Field Charging Strategy: Why technicians are intentionally undercharging slightly and relying more on line length specifications
  • A2L Safety Components: Dissipation boards and refrigerant leak sensors—their function, failure rates, and nuisance alarms
  • Refrigerant Stratification Theory: Potential explanations for delayed equilibrium involving density differences and non-condensable behavior
  • Industry Politics: The R-454B vs. R-32 debate, GWP legislation, and lobbying efforts that shaped current refrigerant standards
  • Manufacturer Accountability: Warranty support issues, untested components, and the financial burden on contractors
  • Recovery and Reuse Concerns: Questions about blend consistency when recovering R-454B and tank contamination issues
  • Future of HVAC: Discussion of heat recovery chillers, secondary fluid systems, and emerging refrigerant-free technologies
  • Pressure Testing Requirements: New legislation requiring extended pressure tests and improved brazing practices
  • Practical Field Advice: Using thermal imaging to diagnose condenser behavior and verify proper refrigerant distribution

 

Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.

Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

Subscribe to our podcast on your iPhone or Android.

Subscribe to our YouTube channel.

Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.

Follow this show on AudioBrevity and new episodes get summarized for you. Create a free account

Couldn't load the audio. A blocker may be stopping the show's tracking links. Open the file