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New furnace but cold on 2nd floor

Hi - I have a 1yr old Rheem 95% gas hot air furnace. I normally keep it low (about 63) but when it's on it blows very strong and the air on the first floor is semi warm coming out. On the 2nd floor cool air comes out of the vents.

The ducts are not insulated in the basement.

Any thoughts?


  • Jamie Hall
    Jamie Hall Member Posts: 23,272
    Start by

    insulating the ducts.  If you want warm in the basement, put an outlet with a damper on it down there.

    I hope the ducts to upstairs are in a warm space, and not in the outside walls.  If they are, and aren't heavily insulated, there's another potentially big problem.

    Second, check the balance of the air flow -- are you getting the air flow you expect?  If not, are there dampers to balance the flow?

    Can the air return freely from upstairs?  Even if the ducts flow properly, if the air can't get out of a room easily it certainly isn't going to get in easily.

    Third, hopefully the furnace was sized properly for the system...

    Just for starters.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • unclejohn
    unclejohn Member Posts: 1,833
    You may

    Not have the correct speed settings on the fan. Most are set with dip switches and the default settings are normally for the max air flows.
  • Jim Davis_3
    Jim Davis_3 Member Posts: 578
    No heat

    Check the temperature in the ducts right off the plenum on the furnace.  It may not be coming out hot.  Newer furnace do require 50% more airflow than old furnaces.  If the airflow was low the air would be hot-hot.  It is rare the airflow on these new furnaces is too fast.  Sounds like the furnace might not be firing at the correct firing rate.