I would like an opinion what would make sence.
I had furnace replaced 3 yeas ago by Hvac guy "ex friend" who got me new bryant 100k btus, 1570 cfm. My house 1450 sqf according to software calculation needs 55k-60k furnace. Do i upgrade duck to proper size OR get new proper furnace and still need to upgrade ducks?
House is 25 years old , ducks uninsulated, a/c is 2.5 tons.

Thanks