Figures 3 and 4 show respectively the relative comparisons of theoretical capacity and energy efficiency ratio (EER) of R32 over R410A at various evaporating (Te) and condensing (Tc) conditions based on standard 20ºF superheat and 15ºF liquid subcooling per AHRI 540 standard assuming equal volumetric and overall isentropic efficiency. As can be seen, R32 has theoretically 3-14% higher capacity in the A/C operating range (45-55°F Te) and 7-16% higher capacity in the H/P operating range (-10° - 30°F Te). Correspondingly, R32 has theoretically -1% to +5% higher EER in the A/C cooling operating range and 0% to 7% higher EER in the H/P heating operating range, thus little more favorable for H/P than A/C operation. The relative gains increase with lower Te and higher Tc.