AIR-TO-WATER HEAT PUMP
CONTROL
UNITS CONTROL
1 OPERATION FLOWCHART
2 MAIN LOGIC
2.1 Defrosting Mode
2.1.1 The condition of start defrosting mode:
Under heating mode or water heating mode, if the accumulative running time of
compressor is over the set interval time of defrosting(default 50min) ,and the defrosting
temperature(outdoor unit heat exchanger temperature) is lower than the set starting
temperature(default -4℃) ,the unit will start running defrosting, and the 4-way valve will
shut off and the outdoor fan will stop
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