Evaluating R450A as a drop-in replacement for R134a in household heat pump tumble dryers
An investigation into the applicability of R450A as a replacement for R134a in heat pump tumble dryers was made in collaboration with Gorenje, d.o.o.
This paper presents the results of an experimental study evaluating R450A as a possible drop-in replacement for R134a in household heat pump tumble dryers. A heat pump installed in a tumble dryer was equipped with pressure and temperature sensors, and electrical power meters. First, the energy consumption according to the IEC 61121 standard was evaluated using R134a. Then the refrigerant was replaced with R450A and a new optimal charge was determined. The tumble dryer performance was then evaluated again and compared with the previous results. It was found that R450A is a suitable drop-in replacement for R134a in heat pump tumble dryers. The total energy consumption of the tumble dryer decreased by 3.7% and several other benefits such as a better utilized evaporator, and a lower refrigerant temperature at the compressor outlet were observed. Additionally, the refrigerant charge CO2 equivalent was reduced by more than 50%. However, the duration of the drying cycle increased by 4.2%, due to a slightly lower condensing temperature in the heat pump.