HLS 16 is a 1-stage floor heating or cooling controller for individual room temperature control. Both heating and cooling are controlled by using the same thermal actuator. The cooling or heating function can be selected with the external contact. The actuators are controlled time proportionally in about 20 second sequences. Room temperature is detected by an internal NTC10 sensor. The output, controlling heating (red light) and cooling (green light), is proportional to the difference between set point and measured value.