Abstract: The air conditioner is disclosed which determines a stop mode of an outdoor heat exchanger when a difference between a total of a heating power level or levels requested from one or more indoor units and a total of a cooling power level or levels requested from one or more remaining indoor units falls within a predetermined range and, when the stop mode of the outdoor heat exchanger is set, forcedly recovers a regrigerant which is accumulated on the outdoor heat exchanger back to a compressor.

Abstract: A refrigerating circuit apparatus includes a two stage compressor having an upper stage compressing cylinder and a lower stage compressing cylinder, a heat storage tank, an upper stage side variable opening expansion valve and a lower stage side variable opening expansion valve. The upper stage side variable opening expansion valve is controlled toward its closed position for executing a heat storing operation wherein heat is discharged from refrigerant to the heat storage tank. The upper stage side variable opening expansion valve is opened and the lower stage side variable opening expansion valve is closed for carrying out a defrosting operation. Heat stored in the heat storage tank is used in the defrosting operation for removing frost accumulated on an external heat-exchanger during the heating operation.

Abstract: Refrigerating apparatus including a compressor, condensor and a plurality of evaporators which are connected in parallel and controlled by individual electromagnetic valves in response to temperature changes of individual evaporators. The refrigerating apparatus also includes an inverter circuit and a bypass circuit which causes refrigerant to flow from output side of the condenser to the input side of the compressor. When the temperature of the bypass circuit drops because of operation of the electromagnetic valves, the inverter circuit adjusts the operating frequency of the compressor.

Abstract: In a method of controlling a refrigeration cycle constructed by connecting a compressor, an outdoor-side heat exchanger, an expansion valve, and an indoor-side heat exchanger, the temperature of a coolant ejected from the compressor is detected by a sensor, and the opening rate of the valve is adjusted in accordance with the detected temperature. When the detected temperature exceeds a prescribed upper limit, that opening rate of the valve which is indicated on that occasion is stored in a memory, and then the opening rate of the valve is increased to reduce the temperature of the ejected coolant to a lower level than a prescribed lower limit. After the temperature decreases from the lower limit, the opening rate of the valve is adjusted to a larger level than that level which is previously stored in a memory by a prescribed extent, thereby keeping the temperature of the ejected coolant between the upper and lower limits.

Abstract: A Rankine cycle apparatus comprises a circulating pump for circulating a working medium through the apparatus, a gas generator having a tube connected with the outlet side of the circulating pump wherein the working medium flowing in the tube is evaporated, an expander connected with the outlet side of the tube of the gas generator, a condenser having a tube connected between the outlet side of the expander and the inlet side of the circulating pump wherein the working medium flowing the tube is condensed, pressure and temperature sensors for sensing the pressure and temperature of the working medium at the outlet side of the gas generator, and a flow control valve for controlling the rate of flow of the working medium to the gas generator on the basis of the pressure and temperature sensed by the sensors.

Abstract: A humidity-measuring device used with an air conditioner provided with an interior heat exchanger and refrigerant pipe which comprises:a first sensor which is provided at an inlet of the interior heat exchanger and produces a first output signal denoting a temperature of air streams drawn into the interior heat exchanger;a heat conductor positioned in a state extending to the inlet at one end of that portion of the refrigerant pipe, through which the refrigerant flows with a low pressure;a second sensor which is disposed in that portion of the heat conductor which faces the inlet and produces a second output signal; anda system controller which is provided with a memory for storing data on the air humidity corresponding to the first and second output signals, and measures the humidity of the sucked air from the data stored in the memory in accordance with the first and second output signals from the first and second sensors.