A Honeywell Thermostat Sun On is a type of thermostat that is designed to be energy efficient and user friendly. It is a programmable thermostat that can be set to turn on and off at specific times of the day, or to maintain a specific temperature throughout the day. This allows users to save energy by not having to manually adjust the temperature. The Honeywell Thermostat Sun On also has a feature called “Sun On” which is designed to maximize energy savings by automatically adjusting the temperature to match the amount of sunlight coming into the room. This feature helps to reduce energy costs by ensuring that the temperature is not too hot or too cold. Additionally, the Honeywell Thermostat Sun On has a built-in humidity sensor which helps to maintain a comfortable indoor environment. This thermostat is an excellent choice for those looking to save energy and money while still enjoying a comfortable indoor temperature.