Experiment on characteristics of an air source heat pump in false defrosting

For a split type air source heat pump, compares and analyses variation of the parameters such as compressor shaft power, suction and discharge pressures under normal defrosting and false defrosting conditions. Finds that the causes for over high shaft power and discharge pressure of the compressor are no frost on the surface of the outdoor heat exchanger and stopping of the outdoor fan. Presents the principle of the currentlyused defrosting control method with two temperature sensors set in indoor heat exchanger and analyses its shortage.