Zone One™ is a control damper that is designed to solve over-heating and over-cooling problems. Zone One™ consists of a thermostat and a factory wired damper or diffuser that contains an actuator, control module, and duct sensor. The duct sensor senses whether there is warm air (above 72F) or cool air (below 72F) in the branch supply duct. If the Zone One™ thermostat is calling for cooling and the duct sensor senses cool air in the duct the damper will open. Otherwise the damper will remain closed. If the Zone One™ thermostat is calling for heating and the duct sensor senses warm air in the duct the damper will open. Otherwise the damper will remain closed. One thing to keep in mind in using a Zone One™ is to not install a Zone One™ thermostat and damper assembly in the area where the equipment space thermostat is located. The Zone One™ is an inexpensive yet powerful solution to overheating or overcooling problems in commercial buildings.