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.
Search form. Plenum Heater. An electric plenum heater can convert your existing natural gas, propane, or oil furnace into a dual fuel heating system. An electric plenum heater gives you the ability to take advantage of the low-cost dual fuel electric rate and the flexibility to use the most cost-effective heating source at any time.