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Furnace shutdown

I have a utica 90,000 btu hot water furnace.  When I turn the furnace switch off and back on the furnace will run for a short while, then shut back down.  What could be causing this?


    HVACNUT Member Posts: 5,888
    edited March 2023
    Is there a model number for this Utica furnace?
    In order to continue, do you have an electric meter? A manometer? 
    I take it you don't have a service agreement with a heating company.
  • Wakioni
    Wakioni Member Posts: 1
    My Trane high efficiency furnace goes through the start up process flawlessly until the blower motor kick-on step in which the furnace shuts off while the blower continue running cold air. I replaced the pressure switch as the tech recommended but it does not help. Thoughts?
  • pecmsg
    pecmsg Member Posts: 4,965
    edited February 24

    Your tech recommended YOU change the switch?

    HVACNUT Member Posts: 5,888
    The burners fire, then a maybe a 30 second time delay before the blower motor comes on. And when the blower motor comes on, the burners immediately shut off?

    Orthe burners fire, then a few minutes  pass by, the burners shut off, and the blower motor turns on and continues to run?

    If door number 2 is correct, then it seems like a temperature limit is opening. Have the tech tell you to check for 120 volts at the heat speed terminal on the board.
  • mattmia2
    mattmia2 Member Posts: 9,962
    BWT #1 is an immediate safety hazard because it probably means you have a compromised heat exchanger and the pressure from the blower is blowing out the burner.