Generally, the return pressure in a properly operating duct system will be much less than the supply pressure ... a visual inspection of the ductwork will usually turn up most of the leaks. The ...

After sealing the ducts, and going to a variable-speed motor ... We could cut in a second return grille over on this other wall into the return box.” “Exactly,” replied trainer David. “I’d literally ...

During the winter, this setup pulls cold outdoor air in to the house, directly in to the return plenum for the furnace. While a combustion air duct that terminates at the floor will allow cold air ...