A: For example, if you want to control the temperature to be 25℃, the temperature range should be 23°C～27°C. Set the TS value as 25 and DS value as 2, so that the heater could be triggered at 23℃ (TS-DS) and automatically turn off at 25℃. Also, the cooler will be triggered at 27℃ (TS+DS) and automatically turn off at 25℃.