Experimental investigation of split air conditioning unit: exergy and total equivalent warming impact analysis using R32 and R290 instead of refrigerant R410A

The pressure to phase down high-global warming potential (GWP) refrigerants is increasing. This study compares the impact of three refrigerants R410A, R32 and R290 under high outdoor temperature (ODT) in range (30–50 °C) conditions utilizing a split-type air-conditioning system. The measurements were carried out in a calibrated test lab. The results show that exergy destruction increased by increasing (ODT). R410A demonstrated consistently large heat losses, especially in the compressor and condenser. R290 indicated the smallest absolute exergy destruction for most of the components. Generally, R290-based system is the lowest in terms of total exergy destruction by approximately 4–30% less than R410A. R290 shows also an increase in the total equivalent warming impact (TEWI) with the ODT from 30 °C to 50 °C about 35%, but indoor temperatures have small effect on this value about 5%. R32 decreases TEWI by about 20% compared to R410A while R290 is the lowest of about 30% with respect to R410A. These disparities are highlighting the importance of refrigerant selection in climate impact, especially in hot climates. It is concluded that R290 is showing potential as an environmentally friendly refrigerant.