Performance Mapping for Variable Ductless Heat Pump Systems in Heating, Cooling and Defrost Operation

As the market for ductless heat pump systems (DHPs) has grown so has the need to represent their performance in building simulation programs to enable the study of their effect on building energy consumption and to assist in the building design. For computationally efficient building assessments, quick computation for power consumption under different external effects is necessary. In this paper, data from various heating and cooling tests on a 9500 Btu/h (2782 W) unit are presented. In both operation modes, the minimum and maximum capacity under different environmental conditions, the indoor unit power consumption and the part-load performance were modeled from the data. A defrost model was also constructed to adjust the heating part-load model for defrost operation and a sensible heat ratio model was built to capture the humidity removal performance of the DHP in cooling. Good agreement between the measurement and prediction was found