Abstract: An HVAC damper includes a sheet metal frame surrounding a series of pivotal damper blades that are each supported by a pair of plastic bearing members. Each bearing member is a unitary piece that includes a radial bearing, a thrust bearing, a lug for connecting to a damper blade, a shaft-receiving feature for connecting to a drive shaft, and multiple crank pins for selectively connecting to a drive linkage. Choosing which crank pin gets connected to the linkage determines a damper blade's rotational direction relative to the other damper blades. Adjacent damper blades preferably rotate in opposite directions to ensure positive sealing engagement between their adjacent blade tips. The bearing members allow the drive linkage to be installed outside the frame to avoid obstructing the airflow through the damper. During assembly, the bearing members allow the damper blades to be placed within the frame prior to installing the bearing members.

Abstract: An HVAC damper includes a sheet metal frame surrounding a series of pivotal damper blades that are each supported by a pair of plastic bearing members. Each bearing member is a unitary piece that includes a radial bearing, a thrust bearing, a lug for connecting to a damper blade, a shaft-receiving feature for connecting to a drive shaft, and multiple crank pins for selectively connecting to a drive linkage. Choosing which crank pin gets connected to the linkage determines a damper blade's rotational direction relative to the other damper blades. Adjacent damper blades preferably rotate in opposite directions to ensure positive sealing engagement between their adjacent blade tips. The bearing members allow the drive linkage to be installed outside the frame to avoid obstructing the airflow through the damper. During assembly, the bearing members allow the damper blades to be placed within the frame prior to installing the bearing members.

Abstract: A valve extension actuator subassembly for rotating an extending valve stem of an HVAC valve, having a rotational, polymeric, cylindrical, hollow projection body extending on a central axis coaxial with the valve stem, having an inner end and an outer end, and defining a central space therein, a transverse polymeric handle on the outer end of the projection body, a metal valve plate at said inner end of the projection body, rotatable therewith, and receiving the extended valve stem to rotate it, a removable thermal insulative plug in the central space for thermally insulating the subassembly, and a removable cap closing the outer end of the body. Connection of the body to the valve plate preferably includes snap-on detents. The body preferably has drive lugs interfitting with the valve plate. One embodiment has an adjustable memory stop plate serving as the valve plate, the stop mechanism being accessible with a tool extended through the central space of the body after removing the insert and cap.