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dunkirk condensating dcb 165 wall mount High Efficiency boiler error 128

NotAgainNotAgain Member Posts: 2
boiler ran fine after new install in October, now error 128 loss of flame appears every 2-3 days? Could the sensing electro have gone bad already, would it cause this code? Gas pressure is fine. Mbh is 175, no flue clogs.


  • clammyclammy Member Posts: 2,505
    do you know if the unit had a combustion testing done when it was started up and if the installer had gone through the start up check list ,combustion and gas pressure testing aside from programming the controller correctly for the type of system you have . I think you should call the installing company and have them do as I have suggested . Most likely the flame sensor is dirty and needs to be clean and if the combustion is off it will foul the sensor . Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • NotAgainNotAgain Member Posts: 2
    Thanks clammy. I am the installer. I am hesitant to pull the sensor without a replacement gasket. We followed start up procedure to a T and been in contact w the company to change certain parameters. The boiler is natural gas. We r gonna re check combustion readings on Monday to see is anything has changed but all were in speck upon fire up.
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