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Fitting to connect sight glass to a drain valve.

This is my current sight glass https://imgur.com/a/ISoFbsB
and I would like to hook it up with a Dahl 1/4" MIP x Male Hose(https://imgur.com/f9YlwBs).

What fitting size should I get?

Comments

  • 109A_5
    109A_5 Member Posts: 1,385
    Hello @datawaym8,
    I'm assuming your present valve is an 1/8" pipe thread, so an adapter, 1/8"MPT x 1/4"FPT would probably work.
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • Danny Scully
    Danny Scully Member Posts: 1,423
    You don’t need anything, as the sight glass drain size is 1/4”
  • 109A_5
    109A_5 Member Posts: 1,385

    You don’t need anything, as the sight glass drain size is 1/4”

    Normally I would agree but that thread looks kind of small compared to the sight glass OD.
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
    Danny Scully
  • ethicalpaul
    ethicalpaul Member Posts: 5,701
    Mine was both. It has a 1/8 part that can be spun out and then there's a 1/4 part remaining. This one looks the same. So I'd go with the 1/4"
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,818
    edited December 2022
    If you want to be sure, take the part with you to buy the new part(s)

    If you want to get really fancy, in place of a coupling, you can use a 45° elbow to make connecting the hose easier
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • veteransteamhvac
    veteransteamhvac Member Posts: 73
    You could always just add some extra tees and couplings and such to make room for your desired valve. This is just an example, feel free to improvise.