Extended vent runs for excessive-performance items can boost furnace expenditures; manufacturers restrict equivalent size
https://squareblogs.net/eudonawupx/setting-up-an-efficient-heating-system-with-the-right-size-and-type-of-furnace-kwn0
Extended vent runs for high-performance versions can extend furnace costs; producers decrease equal length, infrequently requiring redecorate.