Analysis and Modelling of Heat Pump Performance using a Rolling-Piston Compressor

This paper presents the experimental analysis of a small-scale heat pump system featuring a variable-speed rolling-piston compressor, designed to evaluate its cooling performance under controlled laboratory conditions. The experimental test stand incorporates an outdoor unit consisting of a Mitsubishi MUZ-A09NA compressor-condenser unit and an indoor finned-tube double-row evaporator (MSZ-A09NA), connected through an electronic expansion valve. The refrigerant used in the system is R410A, and only the cooling mode of the heat pump was studied in this investigation. The test stand is equipped with a network of calibrated sensors, including T-type thermocouples and piezoresistive pressure transducers, for accurate real-time measurement of refrigerant temperatures and pressures, as well as air-side temperatures across the evaporator and condenser. Airflow rates are measured using ASHRAE-compliant anemometer traverses, and differential air temperatures are captured using multi-junction thermopiles to analyze heat exchange efficiency. The methodology involves system stabilization under steady-state operating conditions, data acquisition, and performance evaluation through thermodynamic analysis. Key performance indicators such as cooling capacity, compressor efficiency, and COP are derived from the measured parameters. The results demonstrate the operational effectiveness of the rolling-piston compressor in modulating performance and improving efficiency under varying load conditions. This study serves as a foundation for optimizing control strategies and enhancing the energy performance of compact residential heat pump systems.