A thermostat includes a display and an illumination device that is configurable to illuminate the display in a partial illumination mode and a full illumination mode. In the partial illumination mode the illumination device generates a light intensity sufficient to review the settings of the thermostat without generating heat of a sufficient amount to disrupt thermostat measurements. The full illuminated condition is actuated upon interaction with the thermostat. Once interaction with the thermostat is completed the illumination device thermostat returns to the partially illuminated condition.