Abstract: A ceiling damper system that comprises a damper housing having an input opening to accept air from a heating, ventilation and air conditioning HVAC system, and an output opening to supply the HVAC air to a room. The system further comprises a damper mechanism to substantially block the flow of air through the damper housing when the temperature around the housing reaches a predetermined level. Two or more cross members are included, each of which is mounted between fixed points in the ceiling in a position to allow the cross members to support and hold the damper housing. The damper housing rests on the cross members and is mounted to the cross members. A method for mounting a ceiling damper that comprises providing a ceiling damper having a damper housing for accepting air from a HVAC system and providing the HVAC system air to a room. It further comprises mounting at least two cross members across fixed points in a room ceiling in a position to support the damper housing.

Abstract: A mechanical dual temperature damper closing mechanism having a primary link that separates when the ambient temperature reaches approximately 74° F., closing the damper. The new mechanism provides a reliable means for reopening the damper to allow airflow for the control of smoke spread. A secondary link is engaged within the new mechanism to reopen the damper. When the ambient temperature reaches 180° F. the secondary link separates, closes the damper such that it cannot be reopened.