R-438A
For R-438A, replaces is R-22; trade name(s) is Freon™ MO99™; ashrae safety class is A1; gwp is 2264 (2059); compatible lubricant is MO, AB, POE, verified against its source on 2026-08-11.
- Refrigerant
- R-438A verified
- Replaces
- R-22 verified
- Trade name(s)
- Freon™ MO99™ verified
- ASHRAE safety class
- A1 verified
- GWP
- 2264 (2059) verified
- Compatible lubricant
- MO, AB, POE verified
What the source says
Freon™ MO99™ R-438A A1 2264 (2059) MO, AB, POE elastomeric seals require replacement. R-22 Replacements for Great choice in systems where changing to POE oil is not practical,
— chemours.com, retrieved 2026-08-11
What epa.gov says
R-22 Retrofit Blends R-404A R-407A R-407C R-407F R-417A R-417B R-421A R-421B R-422A R-422B R-422C R-422D R-424A R-427A R-428A R-434A R-438A R-507A
— epa.gov, retrieved 2026-08-11
Sources disagree
More than one authority states this, and they do not state the same thing. Both are reproduced with the source each came from — deciding between them is yours, not ours.
Trade name(s)
chemours.com says trade name(s) is Freon™ MO99™, as of 2026-08-11.
Freon™ MO99™ R-438A A1 2264 (2059) MO, AB, POE elastomeric seals require replacement. R-22 Replacements for Great choice in systems where changing to POE oil is not practical,
https://www.chemours.com/en/-/media/files/freon/opteon-freon-general-replacement-guide.pdf
freon.com says trade name(s) is Freon™ MO99, as of 2026-08-11.
Freon™ MO99 (R-438A) is the best overall all performance when using R-407C? match (energy efficiency, capacity, operating pressures, and If R-407C is used without a full oil change to POE, there is mass flow rates) to R-22 in air conditioning applications.
https://www.freon.com/en/-/media/files/freon/freon-mo99-faq.pdf
Sources
- chemours.comhttps://www.chemours.com/en/-/media/files/freon/opteon-freon-general-replacement-guide.pdf
- freon.comhttps://www.freon.com/en/-/media/files/freon/freon-mo99-faq.pdf
- epa.govhttps://www.epa.gov/sites/default/files/documents/Choosing_Right_R22_Retrofit.pdf