Gas engine heat pump (GEHP) is attracting increasing interests owing to the high heating efficiency. However, the refrigerants used in existing GEHPs present high global warming potential (GWP) values, facing the challenge to be phased out. In this work, the heating performances of a water-source GEHP using R134a and low-GWP refrigerant R152a were investigated and compared. The influences of engine speed and evaporator inlet temperature on the refrigerant operating parameters, heating performances, and compressor efficiencies were evaluated. The results indicated that the GEHP using R152a showed higher heating efficiencies, higher compressor efficiencies, lower discharge pressures, and lower natural gas consumption as compared to R134a. As the gas engine speed increases from 1200 rpm to 1600 rpm, the primary energy ratio, isentropic efficiency and volumetric efficiency using R152a have an improvement of 2.6–10.4%, 3.5–10.7% and 5.8–7.3%, respectively, compared to R134a. The comparisons of experimental results indicate that the GEHP can achieve higher heating performance by using low-GWP refrigerant R152a as the drop-in alternative for R134a.

燃气发动机热泵（GEHP）由于高加热效率而引起了越来越多的关注。但是，现有GEHP中使用的制冷剂具有很高的全球变暖潜能值（GWP），面临着逐步淘汰的挑战。在这项工作中，研究并比较了使用R134a和低GWP制冷剂R152a的水源GEHP的加热性能。评估了发动机转速和蒸发器入口温度对制冷剂运行参数，加热性能和压缩机效率的影响。结果表明，与R134a相比，使用R152a的GEHP显示出更高的加热效率，更高的压缩机效率，更低的排气压力和更低的天然气消耗。当汽油机转速从1200 rpm增加到1600 rpm时，一次能源比 与R134a相比，使用R152a的等熵效率和体积效率分别提高了2.6–10.4％，3.5–10.7％和5.8–7.3％。实验结果的比较表明，通过使用低全球升温潜能值的制冷剂R152a作为R134a的替代品，GEHP可以实现更高的加热性能。