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Downsize a furnace or Zoned system
I recently replaced the 50 year old furnace while also converting the basement to an apartment. My tenants are always complaining about it being too cold downstairs as I'm the one in control of the temperature from the upstairs T-Stat.
I have a Goodman Model #CAPF1824B6DB 70,000 Btu gas furnace.
There is a main truck line in the floor cavity that services upstairs and downstairs with return air running right next to it. The unit is in the basement and sits on an outside wall in it's own closet. The basement is 800 sqft. with a great room and a bedroom separated by a wall. Literally two rooms and bathroom.
Options I can think of to get control or more heat to the basement...
Downsize furnace and block off lower heat/cool vents and add some form of heating downstairs?
Dual Zone heating?
Add a gas fireplace downstairs to provide additional heat?