JPS6467568A - Method of controlling inverter tower loading air conditioner - Google Patents

Abstract

PURPOSE: To protect a bellows against damage by setting the upper limit opening of an electronic expansion valve and the lower limit of supercooling and increasing the operating frequency of a compressor by a specified amount when the limits are exceeded respectively thereby requiring installation of a liquid tank. CONSTITUTION: An air conditioner comprising an electronic expansion valve, an inverter control section, a compressor and a frequency control section enters into a control for increasing the command frequency to a compressor by (a) Hz when the cycle enters into insufficient refrigerant operation and the opening of the electronic expansion valve reaches an upper limit N0 . When the frequency is increased to t+a Hz, the quantity of refrigerant to be circulated is increased in the cycle and the condensation pressure is increased thus increasing the degree of supercooling of refrigerant SC in front of the expansion valve. The cycle is stabilized by sustaining the f+aHz state for a predetermined time. If the opening of the electronic expansion valve is still at the upper limit after t0 time later, the command frequency is preferably increased furthermore. When the detected degree of supercooling drops below a set level, the cycle is stabilized by increasing the degree of supercooling.