Philco Model KG7SC 0900-35C gas furnace

[Andrew Smigiel]

I have recently installed a propane furnace, Philco M0del KG7SC 0900-35C ,made by Nordyne , its been oversized. Fan capacity is too great,I added 3 ducts in the basement & ok. Discharge temp. runs about 100 degrees, static pressure .024.The fireing rate is set at low and it been keeping up at -20. Is this ok and is their a way to estimate output. effecency is rated at 92.1