2-stage heat pump, variable speed furnace
We live in a 100+ year old, two-story house in Maryland, and have had seven estimates on retrofitting a new system (heat pump, furnace and duct work). We have narrowed our contractors down to two and would like your input on the best system that we have been quoted. More specifically is it worth the extra money to get the 2-stage outside unit and the variable speed inside unit or is one more important than the other? Winter here can be quite chilly and the summer is horribly humid.
option 1: 16 SEER HP (2-stage) and variable speed oil furnace
option 2: 14 SEER HP (single stage) and variable speed oil furnace
Like I said, our house is old and definitely not the most energy efficient, although we will be replacing a few windows and doors once the new system is installed.
What do you think? Is there going to be a noticeable difference between the two systems in terms of comfort and efficiency? Is it more important to spend the extra money on the inside or outside unit?
Thanks in advance!