R410A as substitute for R22

In addition to R407C, the near-azeotropic mixture listed by ASHRAE as R410A is available and widely used for medium-sized capacities in air conditioning and heat pump applications.

An essential feature indicates nearly 50% higher volumetric refrigerating capacity (Comparison of performance data) compared to R22, but with the consequence of a proportional rise in system pressures (Comparison of pressure levels).

At high condensing temperatures, energy consumption/COP initially seems to be less favourable than with R22.

This is mainly due to the thermodynamic properties. On the other hand, very high isentropic efficiencies are achievable (with reciprocating and scroll compressors), so that the real differences are lower.

Another aspect are the high heat transfer coefficients in evaporators and condensers determined in numerous test series, resulting in especially favourable operating conditions. With an optimized design, the system may achieve a better overall efficiency than with other refrigerants.

Because of the negligible temperature glide (< 0.2 K), the general usability is similar to that of a pure refrigerant.

The material compatibility is comparable to the previously discussed blends, the same applies to the lubricants. However, the pressure levels and the higher specific loads on the system components need to be taken into account.