R-32 is a commodity refrigerant used globally and manufactured by various companies. R-454B is a blend of R-32 (68.9%) and R-1234yf (31.1%), where R-1234yf is a proprietary refrigerant owned by Honeywell.
Since R-454B is a blend of 2 refrigerants, any leak will dissipate one refrigerant more than the other, changing the total composition. Therefore, topping off R-454B will not maintain its optimal blend, resulting in potential degradation of performance. On the other hand, R-32 is not a blend. The chemical composition of the refrigerant in the system will remain the same with any leakage and topping off, without concern of changing the chemical composition or performance. Additionally, R-32 can be topped off in either liquid or gas phase which can make installation and servicing easier than with R-410A or R-454B.
No - an R-410A system wasn’t intended to be charged with an A2L like R-32.
R-32 evaporator coils and air handlers are required to match with a R-32 outdoor units.
Our plan is to make furnaces field convertible from R-410A to R-32 compatible with a PCB field conversion kit.
Leak detection features will be included in products where required based on refrigerant charge quantity. In residential unitary ducted systems, indoor coils and air handlers will include leak detection features that will interrupt the heating or cooling call if R-32 is detected in the airflow. Some ductless (RAQA) products will also have built-in leak detection. However, most RAQA will be below the refrigerant charge quantity requirement and therefore will not require leak detection features.
It is not required, but it is recommended that contractors obtain training for the safe handling and transportation of Class A2L refrigerants. ACCA, ESCO and NATE all provide safe handling and transportation training with certifications. Refrigerant manufacturers also provide training. Daikin provides live training options, VR training, and prerecorded content geared towards technicians and comfort advisors available at www.HVACLearningCampus.com.
If their tools are rated for use with Class A2L refrigerants and are non-sparking, they should be able to use them. A separate set of hoses for each unique refrigerant is required to avoid mixing refrigerants. Existing gauge sets for R410A, R22, R407C, etc. can be used to measure pressures, but they may not have appropriate saturation temperatures for R-32 (and R454B).
Leak detectors for use with A2L refrigerants are now available.
R-32 has slightly higher pressures compared to R-410A, but they are very similar and therefore applied and used in the same manner. Our quality and reliability testing has shown there are no discernable differences.
Yes, R-32 is an allowed refrigerant under the 2024 International Mechanical Code (IMC). The 2024 code includes RCL and LFL, providing more detailed limits that R-32 ultimately adheres to. It is important to use the latest IMC for all your construction. For more information on the code, please refer to: International Mechanical Code (IMC)