The best direct replacements for R22 are "drop-in" HFC blends like R438A (MO99), R407C, R422B, and R417A. These substitutes require minimal or no system modifications and are compatible with the mineral oil already in your existing R22 system.
The "best" R22 replacement depends on whether you are doing a drop-in retrofit (using existing equipment) or upgrading the whole system. For retrofits, the top choices are R407C for maximum efficiency and R422D for easier compatibility. For long-term viability, replacing the system entirely with an R454B or R32 system is recommended.
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.
The best replacement for R-22 depends on your system's configuration. Because R-22 is fully phased out, the most common drop-in substitutes are R-438A (MO99), R-407C, and RS-44b (R-453A). These allow for system retrofits, though complete system replacement is often recommended for aging units.
While true "drop-in" replacements are largely a myth (no alternative performs identically to R22 without adjustments), you can safely retrofit your system. Popular R22 retrofit options include R-453A (RS-44b), R-421A, and MO99 (R-438A).
There is no true chemical "drop-in" replacement for R22; every alternative is a unique blend that requires recovering the remaining R22 and evacuating the system. The best, most widely accepted retrofit refrigerants that require minimal to no oil changes include R-438A (MO99), R-422B (NU-22), and R-427A.
Yes, MO99 (also known as R-438A) is a direct, "no-oil-change" drop-in replacement for R-22. It is specifically engineered to replace R-22 in residential and commercial air conditioning, heat pumps, and refrigeration systems.
Natural resource as substitute
We have come to the conclusion that the best substitute would be Propane (R290). Propane has very similar thermodynamic behavior to R22 and it is a natural refrigerant.
R-22 refrigerant typically costs between $𝟗𝟎 and $𝟐𝟓𝟎 per pound. Because R-22 has been phased out, the supply is dwindling, which causes prices to continuously climb.
R-22 was a commonly used refrigerant that is being phased out because of its harmful impact on the ozone layer. If your HVAC system uses R-22, don't panic — you can still use and maintain your system as normal. But, when it's time for your system to be replaced, you'll need to upgrade to a more sustainable alternative.
There are no refrigerants that can be safely or legally mixed directly into a system with R-22. Doing so can cause catastrophic compressor failure, severe pressure inconsistencies, and oil breakdown.
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.
No, R410A cannot be used in an R22 system. Doing so is dangerous and will destroy the equipment. R410A operates at pressures 40–70% higher than R22, which will cause R22 components (coils, lines) to rupture. Furthermore, the oils are incompatible—R22 uses mineral oil, while R410A requires POE oil.
Prior to 2020, you could still obtain this obsolete product, which is also known as Freon. Although EPA rules prohibited the sale of new systems using R-22 in 2010, HVAC technicians could still buy, sell, and use R-22 to service existing systems. But not anymore! R-22 is now very difficult to source and very expensive.
R-454B is not a drop-in replacement for R-410A or R22. While R-454B shares many characteristics with R-410A, its use is restricted by codes and regulations to systems specifically designed for it. The same is true for R32.
The Key Differences Between R22 & R32
R22 loses on both fronts. This gas has a medium ozone depletion potential, which is too high to be approved for any use. Meanwhile, its global warming potential is 1810. R32 has a zero ozone depletion potential and a GWP of 675.
If you're interested in learning how to refill R22 in your air conditioner, it is important to know that this is not something a homeowner can do on their own. Due to complexity, safety concerns, training and licensing required we do not recommend doing this without having a trained professional onsite.
It is possible to use a different type of refrigerant inside an R-22 system. There are “drop-in” refrigerants that serve exactly this purpose. When someone has an R-22 leak, it's possible to remove all the R-22 from the system and replace it with a drop-in refrigerant.
Yes, R-22 is highly scarce and very expensive. Because production and importation were completely banned in 2020 due to environmental regulations, supply now relies entirely on recycled or stockpiled amounts.
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. Lower Discharge Pressure compared to R-407A, R-407C and R-427A.
As of January 1, 2020, the United States banned the use of the R22 refrigerant, commonly known as Freon.
The best replacement for R-22 depends on your system's configuration. Because R-22 is fully phased out, the most common drop-in substitutes are R-438A (MO99), R-407C, and RS-44b (R-453A). These allow for system retrofits, though complete system replacement is often recommended for aging units.
A 30-pound cylinder of R-22 refrigerant is generally worth between $500 and $1,200 to purchase wholesale, and up to $2,400 to $4,500 if bought directly from a service company during a home repair.
MO99 (R-438R) by Freon offers the closest performance match to R-22.
No, you should never mix MO99 (R-438A) with R-22.