What Are the Disadvantages of R407C Refrigerant?
R-407C is an HFC blend (R-32 / R-125 / R-134a) that was commonly used as an R-22 replacement. While it served as a practical transitional refrigerant, it has several notable disadvantages that limit its appeal in modern HVAC applications.
Key Disadvantages of R-407C
1. Not a Drop-in Replacement
R-407C is not a direct, drop-in substitute for R-22. Converting systems often requires changes to oil type, system components, and service procedures. Retrofits can be more complex and costly than anticipated.
2. High Temperature Glide
R-407C is a zeotropic blend with a relatively high temperature glide (typically ~5–7°C). This means phase change occurs across a range of temperatures, which can reduce heat-exchanger effectiveness and make system performance less predictable.
3. Lower Energy Efficiency
Compared with newer refrigerants such as R-410A, R-32, or modern low-GWP HFO blends, R-407C often delivers lower COP/EER. Lower efficiency leads to higher operating costs over the life of the equipment.
4. Relatively High GWP
Although R-407C has zero Ozone Depletion Potential (ODP), its Global Warming Potential (GWP) is relatively high (around ~1774). This makes it less favorable under current and evolving low-GWP regulations and corporate sustainability goals.
5. Composition Shift on Leakage
Because it is a multi-component zeotropic blend, R-407C’s composition can change when the refrigerant leaks. Partial recharge with a single component or mixed refrigerants can degrade performance and require full recovery and recharging to restore correct composition.
6. Declining OEM Support
Major HVAC manufacturers have moved toward R-410A, R-32, and other low-GWP alternatives. New equipment and spare parts for R-407C are becoming less common, reducing long-term support for systems designed around R-407C.
Conclusion
R-407C was useful during the transition away from R-22, but its high temperature glide, moderate efficiency, high GWP, and retrofit complexity make it a less attractive option today. For new installations, low-GWP alternatives such as R-32, R-454B, and other next-generation refrigerants are generally preferred.