Abstract: An air conditioner includes an indoor unit, an outdoor unit, an outdoor expansion valve, an indoor expansion valve, and a controller. The controller executes first control and second control. The first control includes stopping cooling operation or heating operation if a first condition is satisfied during cooling operation or heating operation, and then starting cooling operation or heating operation if a second condition is satisfied. The first condition indicates that a heat load in a target space is low. The second condition relates to the heat load in the target space. The second control includes setting opening degrees of the outdoor expansion valve and the indoor expansion valve upon a start of cooling operation or heating operation according to the first control to be larger than opening degrees upon satisfaction of the first condition.

Abstract: A heat exchanger includes: a first heat transfer tube; a second heat transfer tube; and a branching tube having a first end connected to an end of the first heat transfer tube, a second end connected to an end of the second heat transfer tube, and a third end, and connecting the first end, the second end, and the third end to each other. The first heat transfer tube is larger in heat exchange quantity than the second heat transfer tube. The branching tube has a first flow path connecting the first end with the third end, and a second flow path connecting the second end with the third end. The first flow path is shorter than the second flow path. The branching tube includes: a U portion; and an inflow portion having an end connected to the U portion.

Abstract: An air conditioning control system includes an air conditioner, a setting unit, a control unit and a learning unit. The air conditioner performs air conditioning in a room. The setting unit sets a first temperature and a second temperature. The first temperature is a target temperature for a first area in the room. The second temperature is a target temperature for a second area in the room. The control unit controls the air conditioner so that a temperature of the first area approaches the first temperature and a temperature of the second area approaches the second temperature. The learning unit learns control of the air conditioner so that the temperature of the first area approaches the first temperature and the temperature of the second area approaches the second temperature.