iO HVAC Controls D-Z1-06 Zone One 6" Damper AssemblyiO HVAC Controls D Z1 06 ACTUATORS ARE INSTALLED ON 2ND DIMENSION Zone One 6" Damper Assembly The Zone One two position, stand alone damper is a control damper assembly designed to solve over heating and over cooling problems. It can be used to control a single room, or by using multiple dampers, zone multiple rooms. The damper is wired to a thermostat in the room or area that is too hot or too cold. Using a duct temperature sensor mounted on the