High Efficiency Furnaces - issues?

Tremolux

After a great deal of searching and research, and numerous delays, we've decided that none of the "trick" solutions we've researched are really suitable for the 2 story brick house we're restoring. The original radiators, circa 1930, were removed due to cracking from repeated freezing, and we just can't take the risk of having old pipes go bad.



The "conventional" approach will be to put one furnace in the attic, for the 2nd floor, and another one in the basement to handle the 1st floor. Our contractor has recommended a pair of the 98% Lennox models with 2 stage heat and a variable speed motor.



Are there any issues with these units that we should know about? ( price is not our major concern )



Are there any significant differences between these and similar models from other manufacturers?



Do very high efficiency models require more frequent routine servicing?



Is a variable speed fan and 2 stage heat the current "state of the art"?



Would a two or three speed fan work as well?



Any other helpful suggested are welcome.



Thanks for your time and attention.

martin

high end furnaces

The 2 stage variable furnace is a nice furnace, I like the newer modulating furnace but not all mfgs. have them. I think all major brands are quality units and the quality of the installation and dealer is what sets them all apart.

Brad White

One thing I have always noticed

is that the higher efficiency furnaces move more air but at a lower temperature. Because yours is a "new" system, you will not have an issue provided that the ductwork is sized to the delivered air volume (CFM).



But I mention this in general that when retrofitting a new high efficiency furnace to an existing duct system, the air flow rates are often more than the duct system can practically handle in a quiet way. FYI



While you go about your project, do not skimp on the return paths. Use the rules, good duct design and seal heck out of the ductwork too. Pays dividends.