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Weil McLain condensate trap accumulating water

quaker120 Member Posts: 2
edited March 16 in Gas Heating
I have a Weil McLain gas boiler. Every few weeks, it fails to complete the startup cycle and throws a pressure switch error. When this happens, the internal condensate trap is full of water (the side of the trap where the white tubes connect). If I empty the water out of the trap, the furnace starts fine.

Here is a picture of the trap that I'm referring to (without water, I just drained it this morning)

Does anyone know why the water accumulates in the trap, and what I can do to prevent it?



  • Jamie Hall
    Jamie Hall Member Posts: 23,276
    Something is blocking the drain -- bad slope, kinked, something stuck in it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • quaker120
    quaker120 Member Posts: 2
    Thanks, Jamie! I will check the drain.
  • Big Ed_4
    Big Ed_4 Member Posts: 2,783
    Make sure there is an air gap on the drain....
    I have enough experience to know , that I dont know it all
    HVACNUT Member Posts: 5,829