Even though we have only one finished room (a guest room) on the
second floor of this new house, looking ahead to the time when the
rest of the 2nd floor may be finished, our HVAC subcontractor put in a
large furnace and AC for it, one big enough to take care of several
rooms. The problem now is the noise. When it comes on, it sounds
like a jet plane taking off. The subcontractor has suggested
diverting a large part of the furnace/AC output into the unfinished
attic space, but that will mean that most of what we pay for up there
will be wasted. Can anyone suggest other solutions?

Thanks for any comments.