Air-conditioner and operation control method thereof

A method for controlling an operation of an air-conditioner comprising:

• operating a small-capacity compressor;
• making the pressure of a suction end of a refrigerant channel and a pressure of a discharge end of the refrigerant channel of a large-capacity compressor equal while the small-capacity compressor is being operated;
• and
• actuating the large-capacity compressor after making the two pressures equal.

A method for controlling an operation of an air-conditioner comprising:

• a first step in which, in case of a cooling operation, a small-capacity compressor and a large-capacity compressor are actuated, and then, when a value of a room temperature varied by the actuated small-capacity compressor and large-capacity compressor is smaller than a value obtained by subtracting a pre-set first temperature from a desired temperature set by a user, the small-capacity compressor and the large-capacity compressor are stopped;
• a second step in which in a state than the small-capacity compressor and the large-capacity compressor are stopped, when the value of the room temperature is greater than a value obtained by adding a pre-set second temperature to the desired temperature, it goes back to the first step;
• a third step in which the first and second steps are repeatedly performed as many as the pre-set number of times;
• a fourth step in which only the small-capacity compressor is controlled to satisfy a relation of (desired temperature−pre-set first temperature≦room temperature≦(desired temperature−pre-set second temperature);
• a fifth step in which when the value of the room temperature is greater than a value obtained by adding a pre-set third temperature to the desired temperature, a valve is operated for a certain time and then stopped;
• and
• a sixth step in which the large-capacity compressor is actuated.

An air-conditioner comprising:

• a small-capacity compressor and a large-capacity compressor for compressing a refrigerant to a high temperature high pressure gaseous refrigerant;
• a valve for connecting a suction opening of a refrigerant channel of the large-capacity compressor and a discharge passage of a refrigerant channel of the large-capacity compressor;
• and
• a controller for performing a controlling operation by the following steps comprising:
• a first step in which, in case of a heating operation, a small-capacity compressor and a large-capacity compressor are actuated, and then, when a value of a room temperature varied by the actuated small-capacity compressor and large-capacity compressor is smaller than a value obtained by subtracting a pre-set first temperature from a desired temperature set by a user, the small-capacity compressor and the large-capacity compressor are stopped;
• a second step in which in a state than the small-capacity compressor and the large-capacity compressor are stopped, when the value of the room temperature is greater than a value obtained by adding a pre-set second temperature to the desired temperature, it goes back to the first step;
• a third step in which the first and second steps are repeatedly performed as many as the pre-set number of times;
• a fourth step in which only the small-capacity compressor is controlled to satisfy a relation of (desired temperature−pre-set first temperature≦room temperature≦(desired temperature−pre-set second temperature);
• a fifth step in which when the value of the room temperature is greater than a value obtained by adding a pre-set third temperature to the desired temperature, a valve is operated for a certain time and then stopped;
• and
• a sixth step in which the large-capacity compressor is actuated.