The best and most popular drop-in replacement for existing R-22 air conditioning systems is Freon MO99 (R-438A) or RS-44b (R-453A). These are designed as direct "drop-in" replacements, meaning they require no expensive system modifications, oil changes, or new metering devices.
Since Freon MO99 is the closest capacity match to R-22, compared with most of the other no-oil change refrigerants, it will reach the desired set point before other, lower-capacity refrigerants. With Freon MO99, residents are unlikely to know a different refrigerant is even being used.
Chemours has developed a new generation of low global warming potential (GWP), hydrofluoroolefin (HFO) based refrigerant replacements for Freon™ 22 in new and retrofitted equipment. See Opteon™ XP40 (R-449A).
Freon™ 407C has been a popular R-22 replacement because of its properties, which include: Similar cooling capacity, energy efficiency, and pressures as R-22 in systems. An ability to be topped off after a leak, multiple times, with minimal impact on system performance.
Comstar RS-44b is the closest, market available drop-in replacement for R22 that requires no oil changes and no system changes. Other features include: Equal Flow Rate & Cooling Capacity as R22.
You cannot just switch refrigerants because R410-A and R-22 have different chemical properties. R410-A operates at a higher pressure. If you put R410-A into an R-22 system, the parts will rupture due to the increased force. You can convert your current system to one that runs on R-410A, but the cost will be high.
Yes. The mass flow rate and operating pressures of Freon™ MO99 are the closest of all the mineral oil compatible replacement products and will likely perform adequately in an existing R-22 system with a capillary tube expansion device.
Freon™ 407C will have higher discharge pressures and lower discharge temperatures when compared to R-22 operation.
If you put R410-A into an R-22 system, the parts will rupture due to the increased force. Mentioned above, R410A is a higher-pressure refrigerant than R-22 and has a lower boiling point.
As of January 1, 2025, the sale of R-407C is prohibited because its Global Warming Potential.
A2L refrigerants, the new refrigerants for 2026, will replace R-410A in new systems. A lot about A2L refrigerants is explained in their name: The “A” means low toxicity. The “2L” is a safety classification, indicating it is mildly flammable.
The most common r22 replacement refrigerants include R407C, R422D, and R438A (MO99). Each offers different advantages in terms of compatibility, cost, and environmental impact.
R410A is a near-azeotropic refrigerant composed of 50% R32 and 50% R125, with ODP = 0. It is mainly used as a substitute for R22 refrigerant. It has a higher cooling capacity per unit volume and good heat transfer and flow properties, but its pressure values are about 60% higher than R22 at the same temperature.
For example, when replacing R22 with R134a, there are many problems that cannot be replaced directly; the cooling power of R134a is 60% lower than that of R22, which means that the condenser of the system must work overtime to achieve the same cooling capacity. R134a is not good for rubber parts and can cause leaks.
Freon™ MO29 also appropriate for stationary DX air conditioning applications, including DX water chillers. Freon™ MO29 refrigerant: Extends system life using the same equipment as R-22, so a system with an R-22 leak does not need to be completely replaced or upgraded. Offers similar capacity and efficiency as R-22.
Because R290 has similar saturated pressure-temperature characteristics and volumetric refrigerating capacity as R22, is miscible with the oils typically used in R22 compressors, is relatively cheap and is reported to yield favourable efficiency, it is often deemed as a desirable option to use in existing R22 systems.
Homeowners without EPA certification are not authorized to purchase or recharge systems with r410a refrigerant. Doing so could violate federal law and void manufacturer warranties on your HVAC system. Even if you find listings online that suggest otherwise, be cautious.
Transition from R-22 to R-410A
In the EU and the US, R-22 could not be used in the manufacture of new air conditioning or similar units after 1 January 2010. In other parts of the world, the phase-out date varied from country to country.
Beyond pressure, the two refrigerants use different oils for lubrication; R22 systems use mineral oil, while R410A requires synthetic oil, which doesn't mix well with R22. These compatibility issues can lead to inadequate cooling, component wear, and even long-term system failure.
Mixing R22 with R407C
According to the 609 EPA rule, mixing refrigerants is illegal and anybody caught doing so will be heavily fined. Although you may this restriction is primarily political we would like to give you a basic education to explain the two most devastating effects of such action: To the environment.
The squeezed refrigerant moves through the system without carrying much, and the AC keeps on working without cooling. So, if you feel warm air blowing from your air vents when the system is set to cool your home, that's a clear sign of overcharged refrigeration.
At 90°F, typical R-22 system pressures are about 250 psi high side and 40-45 psi low side. High side pressure around 250 psi is normal if the condenser is clean and airflow is adequate. Low side at 43 psi indicates proper suction pressure. Check for refrigerant overcharge or restricted airflow causing high pressure.
Although they're both refrigerants, the higher efficiency of R-410A requires an upgrade to the equipment. For example, plan to replace the refrigerant tubing, the evaporator, condenser, and compressor. Other components might also need updates.
MO-99 is already a blend of five refrigerants, what difference does R22 make? They both are mineral oil compatible, and have the same boiling points. I haven't bought a virgin can of R-22 in ten years. Mixing is not recommended, because you know, they are in the business of selling refrigerant.