| Option | GWP (AR4) | GWP Change | Safety Class | Type | Capacity vs Existing | COP vs Existing |
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How to Use the Refrigerant Conversion Calculator
Choose the refrigerant now in the system: R-22, R-410A, R-404A, R-507A, R-407C or R-134a.
Pick the operating point that matches the system, such as air conditioning or medium-temp refrigeration, and the approximate age of the equipment.
Press Find Replacement Options to see each retrofit, service or new equipment option with GWP change, safety class, oil, glide and capacity match.
Recover the existing refrigerant, follow the refrigerant and equipment manufacturer procedure, and compare retrofit cost with replacement before you start.
Refrigerant conversion in Canada: retrofit or replace?
Every job on an aging system comes down to one decision: change the refrigerant in the existing equipment, keep servicing it as it is, or replace the equipment with a unit designed for a lower-GWP refrigerant. This tool lists the realistic options for the refrigerant in the system and compares each with it at the operating point you pick.
How the capacity match is calculated
For each replacement the tool runs an ideal vapour-compression cycle at your evaporating and condensing temperatures and divides its volumetric cooling capacity by that of the existing refrigerant. For a retrofit into the same compressor, that ratio is a first estimate of how much capacity you keep. COP is compared the same way. The figures leave out compressor volumetric efficiency, expansion valve behaviour and heat exchanger changes, so treat them as a screen and not as a guarantee. Fluid properties come from CoolProp and GWP values are AR4 100-year values for every refrigerant, so the percentages compare like with like. Compare any two refrigerants in more detail with the refrigerant comparison calculator.
What a retrofit involves
Recover all of the existing refrigerant, repair the leak that caused the service call, change the filter-drier, change the oil if the new refrigerant needs a different one, and check the expansion device. Never top up with a different refrigerant, because the mixture cannot be reclaimed and the pressures will not match either fluid. Find and fix leaks first with the refrigerant leak finder, then weigh in the new charge with the refrigerant charge calculator. Blends with glide change how you read superheat and subcooling, so use the dew point for superheat and the bubble point for subcooling.
R-22 systems
R-22 is an HCFC, and HCFCs are controlled under the federal Ozone-depleting Substances and Halocarbon Alternatives Regulations. The regulations prohibit manufacturing products designed to contain R-22 and require recovered HCFCs that are no longer needed to go to a recycling or reclamation facility. At 5°C and 45°C, R-407C keeps 95% of the R-22 volumetric capacity with a 96% COP match and 6.2 K of glide, while R-422D keeps 84%. The R-422D GWP is 51% above R-22 on the AR4 basis, so it lowers the cost of the retrofit more than it lowers the climate impact.
R-410A systems
No refrigerant is a drop-in for R-410A. R-454B keeps 98% of the capacity at 5°C and 45°C, but it has 1.5 K of glide and is class A2L. R-32 has 113% of the capacity and a discharge temperature of 75°C against 62°C. Both need equipment designed and listed for them, so the practical choices are to keep servicing the system with R-410A or to replace it.
R-404A and R-507A systems
R-404A and R-507A have the highest GWPs of the refrigerants here, at 3,922 and 3,985. R-448A, R-449A and R-452A keep 101%, 101% and 99% of the R-404A capacity at -10°C and 40°C, and cut the GWP by 65%, 64% and 45%. R-448A and R-449A have about 6 K of evaporator glide, so convert pressures to temperatures with the PT chart calculator and use the refrigerant blend calculator to see how the blend sets the glide.
R-134a systems
R-134a runs at much lower pressure than R-404A. At -10°C and 40°C, R-134a has only 62% of the R-404A volumetric capacity, so the two are not interchangeable. R-513A and R-450A are the low-pressure options, at 99% and 87% of the R-134a capacity at 5°C and 45°C. R-1234yf is class A2L and is intended for vehicles and equipment designed for it.
Canadian HFC rules and what they mean for service
Environment and Climate Change Canada says the regulations decrease the supply of HFCs allowed into Canada step by step, and that they also reduce demand in manufactured products. That affects the supply and price of high-GWP refrigerants over the life of a system. The ECCC page on the regulations has the details, and the refrigerant phaseout guide sets out the timeline by refrigerant.
Retrofit or replace the equipment?
A retrofit only makes sense when the rest of the system is sound. If the compressor, coils or controls are near the end of their life, a refrigerant change spends money on equipment that will be replaced soon. Compare the retrofit with a new installation using the HVAC replacement cost calculator, and check the manufacturer warranty before you change the refrigerant in newer equipment.
Frequently Asked Questions
The usual retrofit options are R-407C and R-422D. At 5°C evaporating and 45°C condensing, R-407C gives 95% of the R-22 volumetric capacity with 6.2 K of evaporator glide and needs a change to POE oil. R-422D gives 84% and 3.7 K of glide, and the manufacturer allows existing mineral oil in many systems, but its GWP is 51% higher than R-22 on the AR4 basis. Neither is a drop-in, so recover all of the R-22 first and follow the refrigerant manufacturer procedure.
No. Both are for equipment designed and listed for them. At 5°C evaporating and 45°C condensing, R-32 has 113% of the R-410A volumetric capacity and a discharge temperature of 75°C against 62°C. R-454B has 98% of the capacity and 1.5 K of glide, where R-410A has almost none. Both are class A2L. Keep servicing an R-410A system with R-410A, and consider the lower-GWP equipment when the system is replaced.
R-448A, R-449A and R-452A are the usual retrofit refrigerants. At -10°C evaporating and 40°C condensing, R-448A gives 101% of the R-404A volumetric capacity and cuts the GWP by 65%. R-449A gives 101% with a 64% cut, and R-452A gives 99% with a 45% cut. R-448A and R-449A have about 6 K of evaporator glide, so read superheat from the dew point. Recover all of the R-404A first and check the expansion valve.
R-134a runs at much lower pressure than R-404A or R-410A, so only low-pressure refrigerants match it. At 5°C evaporating and 45°C condensing, R-513A gives 99% of the R-134a volumetric capacity and R-450A gives 87%, with GWP cuts of 56% and 58%. R-1234yf gives 92%, but it is class A2L and is meant for vehicles and equipment designed for it, not for retrofits.