What is low ambient control?
This is a control device which allows an air conditioning system to provide indoor cooling when the external ambient temperature is low, such as in winter. It is needed, for example, when an area has a high year-round heat gain so causing the air conditioning to run all year. Fitting a low ambient control prevents the evaporator from freezing. The most common method is to vary the speed of the condenser fan in order to maintain the head pressure (or high-pressure side) of the refrigeration system. Thus, low ambient control is often also known as head pressure control.
