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ultra 155 cycles on and off repetitively

Brotherhr Member Posts: 1
My boiler sounds like it is turning on and off over and over all night sometimes. It makes heat though.


  • Jamie Hall
    Jamie Hall Member Posts: 21,092
    Most likely a control problem -- or a wildly oversized boiler with no buffering. But we need a lot more detail on the system -- system size, boiler size, piping, controls...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JUGHNE Member Posts: 10,561
    When was it opened up and serviced last?
    Failing flame sensor has those symptoms.