The international airports in Pennsylvania are Lehigh International Airport at Allentown, Erie International Airport at Erie, Harrisburg International Airport at Harrisburg, Philadelphia International Airport at Philadelphia,
Electric Plenum Heaters. A plenum heater is an electric resistance heating device that is installed in the plenum, which is the spot in the ductwork system where ducting and furnace join. Air is heated as it flows across electric elements and then is distributed through the existing ductwork.
Think of the furnace plenum as the last place air is at your furnace, at itâs highest pressure, before traveling throughout your house. From the outside, itâs really nothing more than a metal box, in simple terms.his is exactly what your furnace plenum does before air is released and delivered. Other terms used for furnace plenum, are âsupply plenumâ or âintake plenum.â. Copyright Â© 2008-2015, HomeRepairgeek.com All rights reserved.