FROSTING/DEFROSTING METHOD FOR INVERTER HEAT PUMP AIR CONDITIONER

摘要

PURPOSE: A defrost control method is provided to minimize user inconvenience and improve efficiency and reliability of system by accurately recognizing the time of frost formation at an outdoor heat exchanger. CONSTITUTION: A method comprises a first step of classifying outdoor temperature into three sections and starting a defrosting operation with different compressor operation time and pipeline temperature for each of the three sections, a second step of lowering, if it is judged as a defrosting operation, operation frequency to a minimum frequency for outdoor control, switching linear expansion valve, and performing defrosting operation at an operation frequency for a predetermined time period if the operation frequency at the start of defrosting operation is higher than a predetermined frequency, a third step of switching a four-way valve, performing defrosting operation at the lowest frequency during a predetermined time period, and performing defrosting operation at a high frequency, and a fourth step of turning off a compressor during a predetermined time period when the defrosting operation is completed.