The Table below summarizes conduction losses, expressed as capacity losses, measured at each air supply register studied. Conduction losses in the ducts, when in cooling mode, raise the supply air temperature. The capacity loss is the energy lost as a fraction of the capacity before cooled air reaches a room. This is because the ducts were located on the roof, where they gained heat from the ambient environment. Summary of average register conduction losses.
Capacity loss is energy loss as a fraction of capacity before reaching the room.
This work was supported by the California Institute for Energy Efficiency and the Department of Energy's Office of Building Technology, State and Community Programs.