A system includes a heat exchanger; a variable actuator in operative communication with the heat exchanger and configured to vary a flow of a first fluid through the heat exchanger in a continuous manner; a discrete actuator in communication with the heat exchanger and configured to vary a flow of a second fluid through the heat exchanger at one of at least two discrete rates; and a controller in communication with the variable actuator and the discrete actuator, wherein the controller is configured to adjust the position of the variable actuator within a range dependent upon a current position of the discrete actuator.