In this introduction to A2L refrigerants, Slipstream presenter Ryan Hoger provides a comprehensive overview of the industry's shift from traditional refrigerants like R410A and R134A to newer, lower-global-warming-potential alternatives, specifically R454B and R32.
This change, driven by environmental regulations, includes a “phase down” process that began in 2022. By December 31, 2024, manufacturers will no longer produce equipment compatible with older refrigerants, marking a complete transition to the new refrigerants by January 1, 2025. Installation deadlines vary: packaged systems can be installed up to three years after manufacture, while split systems must be installed within one year.
The transition to A2L refrigerants introduces certain procedural and equipment changes for HVAC professionals. New refrigerant cylinders will be marked with a red band and will require left-hand threaded adapters, which may necessitate additional equipment adjustments. Tools used with A2L refrigerants must be spark-free to prevent accidental ignition. Installation practices for A2L refrigerants mandate adherence to safety protocols previously recommended for older refrigerants, like purging with nitrogen and evacuation, which are now compulsory.
A2L refrigerants, which are classified under a newly created category by ASHRAE standards, are mildly flammable but challenging to ignite, positioning them as safer options for broader HVAC adoption.
A notable feature in A2L-compatible systems is the integration of refrigerant leak detection sensors and control boards, designed to enhance safety by intercepting thermostat signals and shutting down the compressor and other potential sources of ignition if a leak is detected. These systems can dissipate leaked refrigerants by turning on fans to prevent accumulation in a single area, further reducing risk.
For larger, package systems, the same controls apply, although factory wiring simplifies the installation process by eliminating the need for field piping.