To operate properly, a thermostat must be located on an interior wall away from direct sunlight, drafts, doorways, skylights, and windows. It should be located where natural room air currents (warm air rising, cool air sinking) occur. Furniture will block natural air movement, so do not place pieces in front of or below the thermostat. Also make sure the thermostat is conveniently located for programming.
Better performance and efficiency of the thermostats
Prevent “ghost readings” or unnecessary furnace or air conditioner cycling
A variation in the temperature of 1°C saves around 7% of the HVAC energy consumption