In addition the cost to replace metal exhaust to PVC and cutting holes thru the side and/or roof. The maintenance on high efficiency with more parts like 2 heat exchangers. Costlier parts like a $300 80% inducer motor vs $1,500 for a 90%. Then if a 90% furnace is not condensing right it will shut down. Not worth it for me with a furnace in the attic and one in the basement.
Is there any benefit to the sealed combustion chamber?
In addition the cost to replace metal exhaust to PVC and cutting holes thru the side and/or roof. The maintenance on high efficiency with more parts like 2 heat exchangers. Costlier parts like a $300 80% inducer motor vs $1,500 for a 90%. Then if a 90% furnace is not condensing right it will shut down. Not worth it for me with a furnace in the attic and one in the basement.