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I just recently installed a US boiler, Independence - IN-5. Where is the proper skimming port? I installed a valve off the line to the pressure relief valve, seems to be too high. There is a tapping at the bottom of site glass level. Which one should I use to properly skim the boiler?


  • Fred
    Fred Member Posts: 8,542
    There may be a tapping in the boiler block next to the Pressure Relief valve. You should see a knock-out on the back panel. I put a Tee on my Pressure Relief Valve to and use it as a skim port. My boiler is 33 years old and getting a plug out of the boiler block just isn't worth the effort. If yours is new, you should be able to take the plug out and have a proper skim port. Up high, above the normal water level is what you want for skimming. The one at the bottom of the sight glass iss no good for skimming. You want to slowly "skim" water and any oils off of the surface of the water in the boiler.
  • Mark N
    Mark N Member Posts: 1,115
    Did you look in the installation manual? It's tapping L on the block. It's a 1" tapping factory plugged and labeled surface blow off.
  • rudyms31
    rudyms31 Member Posts: 4
  • Danny Scully
    Danny Scully Member Posts: 1,416
    It's actually 1-1/4", manual is wrong for whatever reason.
  • rudyms31
    rudyms31 Member Posts: 4
    thanks will find out today
  • rudyms31
    rudyms31 Member Posts: 4
    you were right Danny it was 1 1/4 fitting, Thanks for your post