The wireless indoor thermostat surface mount 24 h mode 5 up to 35 c homexpert by honeywell thr842dbg with relay box receiver for controlling of the heating or cooling system the room thermostat is placed in the apartment or hung on the wall you can test the signal strength on the thermostat before the installation with preset values and a large display the actual room temperature is shown on the display by pressing the eco key the thermostat will be switched to a temperature of 18 c th