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Manufacturer and instruction sheet

bld999bld999 Member Posts: 47

I figure someone has seen this on a system before, it dates from 2006 in my case. "Simplex" is the brand.
I'm looking for the manufacturer or a user sheet for this gauge, which is also some sort of valve.
It's the valve function that is obscure, and I'd like to read or hear what type and how it is intended operate on a primary loop for a modcon boiler.


  • STEVEusaPASTEVEusaPA Member Posts: 4,142
    Aren’t we looking at a simple temperature gauge?
  • ratioratio Member Posts: 2,442
    How 'bout a pic or two showing the body & piping?

    The outside of that gauge looks like it's supposed to rotate to allow the index marks to point to different temperatures, is that what you're seeing?

  • bld999bld999 Member Posts: 47
    It has a valve feature . When you rotate the face, it opens or closes a valve. It's hard to see, but there is an "off on " printed close to the center of the display face.
    A casual observer might rotate the face to the upright position, which in fact might close the valve if it is mounted on a horizontal pipe run. Big mistake if they don't realize it.
  • bld999bld999 Member Posts: 47
    This setup is in a rental building, so maybe a couple days before I would be able to get more pics. The red plastic rim does not rotate around the gauge face. The face and the red rim rotate as one piece.
    I had a recent service, and the tech put the sharpie line on the face, said line this up with the pipe and keep it there while running.
    I'm just curious who made the thing and what purpose it might have other than temp display.
  • mattmia2mattmia2 Member Posts: 1,314
    is it some sort of thermostatic mixing valve?
  • bld999bld999 Member Posts: 47
    It doesn't mix, it just sits on the primary loop with a second one on the return end. Question is, why would you use a gauge with a valve feature in a primary loop when it is so vague that it is a valve as well, and a simple innocent rotation could close off the near boiler piping?
    Maybe I should just safety wire the things open and leave the curiosity behind! That would work...
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