WATER CHILLER-HEATER UNIT OF AIR COOLED HEAT PUMP AND DEFROSTING CONTROL METHOD THEREFOR

摘要

A water chiller-heater unit of an air cooled heat pump and a defrosting control method therefor. The water chiller-heater unit of the air cooled heat pump comprises a first heating water system and a second heating water system. A first air conditioning heat exchanger (17) in the first heating water system and a second air conditioning heat exchanger (27) in the second heating water system share a fan (10). The method comprises the following steps: detecting an outdoor environment temperature T4 in real time, and detecting running parameters of a water chiller-heater unit of an air cooled heat pump in real time; when the water chiller-heater unit of the air cooled heat pump enters a defrosting mode, determining, according to T4, whether to control the water chiller-heater unit of the air cooled heat pump to run in an alternate defrosting manner; and if the water chiller-heater unit of the air cooled heat pump runs in the alternate defrosting manner, controlling, according to T4 and the running parameters of the water chiller-heater unit of the air cooled heat pump, a first heating water system and a second heating water system to run in an alternate heating manner, such that an air conditioning heat exchanger not in a heat exchange operation state performs defrosting by means of continuous running of a fan. The method performs defrosting by using continuous running of a fan due to switching between systems, thereby improving the heating effect of a water chiller-heater unit of an air cooled heat pump, and improving the user experience.