A valve and actuator assembly comprising: a valve configured to control a flow of liquid into a coil (64,82) or heat exchanger; and a valve actuator configured to control opening and closing of the valve via positioning of a valve closure member; the valve and actuator assembly including a fluid temperature sensor configured to sense actual temperature of the liquid at the valve for freeze determination; characterized in that the valve actuator is configured to calculate a flow rate of the liquid flowing through the valve, and the valve and actuator assembly including a zone air temperature controller configured to determine a position for the valve actuator based on a sensed zone temperature and a desired zone temperature; the valve and actuator assembly including a minimum flow control module configured to determine when the liquid temperature sensed by the fluid temperature sensor is at a freeze temperature setpoint, the minimum flow control module being configured in response to override the zone air temperature controller to provide a higher minimum flow rate to avoid a freeze condition; and the valve actuator configured to provide both the minimum flow rate for freeze protection of the liquid through the valve and a maximum rate, the minimum flow rate providing a minimum amount of flow required to avoid the freeze condition, the valve actuator further configured to control that the minimum flow rate of the liquid is provided through the valve until the temperature of the liquid sensed by the fluid temperature sensor rises above the freeze temperature setpoint by a temperature differential to avoid wasting energy. a valve configured to control a flow of liquid into a coil (64,82) or heat exchanger; and a valve actuator configured to control opening and closing of the valve via positioning of a valve closure member; the valve and actuator assembly including a fluid temperature sensor configured to sense actual temperature of the liquid at the valve for freeze determination; characterized in that the valve actuator is configured to calculate a flow rate of the liquid flowing through the valve, and the valve and actuator assembly including a zone air temperature controller configured to determine a position for the valve actuator based on a sensed zone temperature and a desired zone temperature; the valve and actuator assembly including a minimum flow control module configured to determine when the liquid temperature sensed by the fluid temperature sensor is at a freeze temperature setpoint, the minimum flow control module being configured in response to override the zone air temperature controller to provide a higher minimum flow rate to avoid a freeze condition; and the valve actuator configured to provide both the minimum flow rate for freeze protection of the liquid through the valve and a maximum rate, the minimum flow rate providing a minimum amount of flow required to avoid the freeze condition, the valve actuator further configured to control that the minimum flow rate of the liquid is provided through the valve until the temperature of the liquid sensed by the fluid temperature sensor rises above the freeze temperature setpoint by a temperature differential to avoid wasting energy.