A postmix beverage dispenser including a housing, a water bath, a refrigeration system, a concentrate package compartment, a cooling system for the compartment, and a potable water circuit including a cooling coil in the water bath. The concentrate packages are preferably bag-in-box packages with a flexible tube, and the dispenser includes a peristaltic pump driven by a gearhead motor with an encoder. A flow meter in the potable water line feeds information to the control system which controls the pump speed to control ratio. A ratio card is inserted into a slot in the door to tell the control system the ratio to use for each BIB package. A removable water nozzle improves mixing. An improved subassembly and method for making it is described. The potable water cooling coil is above the evaporator coil and separately removable from the water bath.