The WTS8/9 series touch button thermostat is a temperature control device with an LCD screen that displays the real-time room temperature or the set temperature. Once the temperature is set, it sends an on/off control signal to the air handling unit valve to regulate the temperature according to the occupant's desired comfort. The WTS9 series wall modules work with air handling units and regulate the room temperature by controlling the fan speed and the opening/closing of valves. These modules are generally used to control the valves of air handling units.