Heat exchanger and refrigeration apparatus

A heat exchanger comprising:

• rows of heat exchanging units that are superposed with one another in an air flow direction of the heat exchanger;
• and
• flat multi-hole tubes that:
• extend from a first end toward a second end of the heat exchanging units in the heat exchanging units, and
• comprise gas-side flat multi-hole tubes that each comprise a gas-refrigerant port at one end, wherein
• a refrigerant flows in the flat multi-hole tubes,
• in each row of the heat exchanging units, the flat multi-hole tubes are disposed in a first direction, and
• among the heat changing units, a number of the gas-side flat multi-hole tubes that are included in a front-most row heat exchanging unit on an airflow upstream side of the heat exchanger is less than a number of the gas-side flat multi-hole tubes included in a rear-most row heat exchanging unit on an airflow downstream side of the heat exchanger.