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Weil mclain gv90

Paul_69 Member Posts: 251
What are some things to look for when thermal fuse failed . Inducer started and ran ok and vent seems clear


  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    If the inducer is running then I would check the pressure switch. Actually need a little more information from you.
  • Paul_69
    Paul_69 Member Posts: 251
    Why pressure switch? I was not there.another tech was. I will be going once I have switch to get unit to run again. Can u give me some check points. Thx
  • lchmb
    lchmb Member Posts: 2,997
    Check the differential pressures to see what the draft is running at. Check the length of run on the venting, are you near the edge of it's limit. Check gas pressure's to see if the unit is over fired. Check the burner's for damage, warping or cracking and alignment...Is the unit piped direct vent and if so is it clear...if not is there enough combustion air...
    JUGHNE Member Posts: 10,581
    This boiler might have the HSI that doubles as a flame sensor.
    As it ages it might still be a good HSI, but drops the ball as a flamer sensor. After the inducer fan proves it is next in line for ignition, which it may do. But not work as a flame sensor, fire and drop out and repeat.