Heat exchanger and air-conditioning apparatus

An air-conditioning apparatus comprising:

• a heat exchanger including a first heat exchanger and a second heat exchanger each including
• a plurality of heat transfer tubes extending in a vertical direction and spaced apart from each other in a horizontal direction,
• a first header located at lower ends of the plurality of heat transfer tubes, having an outlet for refrigerant, and configured to distribute or combine the refrigerant, and
• a second header located at upper ends of the plurality of heat transfer tubes, having an inlet for the refrigerant, and configured to distribute or combine the refrigerant;
• a flow control valve provided at an upstream pipe located upstream of the inlet of the second header in the first heat exchanger, the flow control valve being configured to adjust a flow rate of the refrigerant that flows into the inlet of the second header in the first heat exchanger;
• a branch pipe branching off from the upstream pipe which is located upstream of the flow control valve, and connected with the inlet of the second header in the second heat exchanger;
• and
• a controller configured to control the flow control valve in defrosting such that the flow rate of the refrigerant which flows into the inlet of the second header in the first heat exchanger is lower than a flow rate of the refrigerant which flows into the inlet of the second header in the second heat exchanger,
• wherein
• in a polygonal housing, the first heat exchanger and the second heat exchanger are arranged in a flow direction along an airflow that passes between the plurality of heat transfer tubes, as viewed from above,
• the first header and the second header of each of the first heat exchanger and the second heat exchanger each have straight portions extending along sides of the housing and bent portions located close to corners of the housing that connect the sides of the housing and bent in a horizontal direction, as viewed from above, the first header and the second header also having ends that are provided close to other corners of the housing,
• the first heat exchanger is provided on a leeward side in the airflow relative to the second heat exchanger,
• the inlet of the second header of the first heat exchanger is located in a heat-exchange front area that is located on one side of the second header in a direction along a horizontal length, and
• the outlet of the first header of the first heat exchanger and the inlet of the second header of the second heat exchanger are located in a heat-exchange end area that is located far from the heat-exchange front area in the direction along the horizontal length and that is located close to another corner of the housing.