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Steam Sucking Science! Infrared Video of Vacuum Heating a Wall-hung Radiator.

Gordo Member Posts: 852
We installed this wall-hung radiator today. In order to save a bit of time getting the steam to it (and getting the new paint to out-gas odors quicker), we removed the vent and "sucked" the steam into the radiator while my son filmed it with a FLIR to capture a infrared video of the moment.

Notice that while under vacuum, the bottom connection to the radiator allowed water to be drawn up into the radiator from the wet return. A rough calculation of the induced vacuum applied appears to be in the order of 18" H2O.

Sorry for the loud noise!

All Steamed Up, Inc.
"Reducing our country's energy consumption, one system at a time"
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STEVEusaPAErin Holohan HaskellCLambcc816


  • Sailah
    Sailah Member Posts: 826
    Sweet. Someone likes his new Flir toy!

    I was doing a steam monitor install today at Boston University. Brand new boiler room to me and no one knew where the traps were. I whipped out my FLIR and in 3 seconds knew where everything hot was located. Major time saver they are just a great invention.
    Peter Owens
  • PMJ
    PMJ Member Posts: 1,265
    edited March 2017
    This situation is very different than natural vacuum in a closed system. Here a large volume of air is continously flowing through the radiator into the shop vac coming mostly through the dry return creating the slightly lower pressure in the rad. The condensate is dragged back in with the fast moving air. There is no such air flow with natural vacuum and no condensate comes back in this way. Just pointing this out for anyone worrying about such things in trying natural vacuum.
    1926 1000EDR Mouat 2 pipe vapor system,1957 Bryant Boiler 463,000 BTU input, Natural vacuum operation with single solenoid vent, Custom PLC control
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,490
    I am so grateful for this. Nothing beats a visual, Thanks, Gordo!
    Retired and loving it.
  • Koan
    Koan Member Posts: 436
    @gordo That picture of you does you no justice! :)
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,490
    I think it makes him look like a superhero. Glowman?
    Retired and loving it.
  • AMservices
    AMservices Member Posts: 610
    Wouldn't it be nice to heat all the radiators with the use of a vacuum.
    Oh Yeah! You can