| 摘要 |
PURPOSE: A method for controlling defrost operation for cooling/heating air conditioner is provided to reduce frequency of defrost operation and achieve an improved system efficiency. CONSTITUTION: A method comprises a step(S410) of judging whether the temperature of the coil of outdoor heat exchanger is lower than 0 Deg.C; a step(S412) of sensing the temperature change state if the temperature is lower than 0 Deg.C; a step(S414) of judging whether a predetermined time period(N) has lapsed if no change exists in the temperature or the temperature is lowered; a step(S416) of judging whether the temperature change is constant, if a predetermined time period has lapsed; a step(S418) of judging whether the current coil temperature is lower than a predetermined temperature(X) for performing defrost operation; a step(S422-S426) of performing defrost operation by turning off the indoor fan, outdoor fan and compressor, turning off the four-way valve and turning on the compressor, if the coil temperature is lower than the predetermined temperature; a step(S428,S430) of judging whether the temperature of coil of the outdoor heat exchanger is higher than a predetermined temperature(Y), and turning off the compressor if the temperature of coil is higher than the predetermined temperature; a step(S432,S434) of performing heating operation by turning on the four-way valve and turning on the compressor and outdoor fan; and a step(S436,s438) of comparing the temperature of coil of the indoor heat exchanger with a predetermined temperature(Z) for performing heating operation, and performing heating operation by turning on the indoor fan if the temperature of coil is higher than the predetermined temperature.
|
