We just had a 90+% efficient furnace installed. The pros and cons, as I see them, is that with a very efficient furnace you use less gas to heat your home so you save money. It burns the gas more efficiently. The trade off is that the unit costs more and the installation may even cost a bit more because these furnaces use a separate intake and exhaust system that are PVC pipes that exist out the side of your house instead of using the chimney for exhaust like the lower efficiency furnaces do (at least my Carrier model does this). Also, these furnaces are more complex so reliability may be an issue and the cost to fix may be higher. But I figure that I’m going to be in this house for the next 20+ years so I’ll recoup the extra cost of the unit down the road, and the warranty is 10 years on parts and a lifetime for the heat exchangers. And it’s so quiet as well.
