On Fri, 19 Oct 2007 16:10:27 GMT, PaPaPeng wrote
Re Furnace install Questions:

Look at the labels inside your current furnace. There should be a BTU
rating somewhere. A close BTU match for your new furnace is what you
atre looking for.

Bingo! The OP never said anything about the replacement being
motivated by over/under capacity of his old unit.