Share 'Residential Ceiling Diffuser with Duct Sealing Issues - Courtesy of Fluke Coproration - ©2010'

This is an infrared image looking up at the 1st story ceiling of a home. Leaky ductwork appears to be untentionally heating the area between a first and second story. (At least it is within the building envelope and not in the attic.... still not very efficient, however.)