A refrigerator door comprising: a front panel that defines a first exterior portion of the refrigerator door; a door liner coupled to the front panel and configured to define a second exterior portion of the refrigerator door ; an insulation space defined between the front panel and the door liner, wherein the insulation space comprises a heat insulating material ; a touch sensor assembly , configured to press against the front panel and sense a touch, the touch sensor assembly comprising a touch sensor mounted to a sensor printed circuit board, PCB, , wherein a sensor connector extends from the sensor PCB; a display assembly configured to display an operation state of the refrigerator on the front panel; a display connector located at the display assembly , and configured to connect electrically to the sensor connector ; wherein the sensor connector comprises: a PCB extension portion extending from the sensor PCB to a position at which the sensor connector couples to the display connector ; and a terminal located at an end portion of the PCB extension portion , configured to connect electrically with the display connector ; wherein the refrigerator door is configured to receive the display assembly through the insulation space into a space between the front panel and the door liner , wherein the display assembly comprises a touch sensor controller and the sensor connector and the display connector are configured to couple to each other when the display assembly is inserted into the refrigerator door . a front panel that defines a first exterior portion of the refrigerator door; a door liner coupled to the front panel and configured to define a second exterior portion of the refrigerator door ; an insulation space defined between the front panel and the door liner, wherein the insulation space comprises a heat insulating material ; a touch sensor assembly , configured to press against the front panel and sense a touch, the touch sensor assembly comprising a touch sensor mounted to a sensor printed circuit board, PCB, , wherein a sensor connector extends from the sensor PCB; a display assembly configured to display an operation state of the refrigerator on the front panel; a display connector located at the display assembly , and configured to connect electrically to the sensor connector ; wherein the sensor connector comprises: a PCB extension portion extending from the sensor PCB to a position at which the sensor connector couples to the display connector ; and a terminal located at an end portion of the PCB extension portion , configured to connect electrically with the display connector ; a PCB extension portion extending from the sensor PCB to a position at which the sensor connector couples to the display connector ; and a terminal located at an end portion of the PCB extension portion , configured to connect electrically with the display connector ; wherein the refrigerator door is configured to receive the display assembly through the insulation space into a space between the front panel and the door liner , wherein the display assembly comprises a touch sensor controller and the sensor connector and the display connector are configured to couple to each other when the display assembly is inserted into the refrigerator door . <EOS>