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Steam Rad supply gate valve "Stem Horizontal"?

SteamFTW Member Posts: 76
Over the years I've seen comments on HH that suggest--if you have to use a gate valve in place of a the usual angle or straight steam radiator valve--installing the gate valve with the "stem horizontal".

Anyone know the reasoning behind this recommendation? Does it depend on the specific type of gate in the valve. I've seen valves with two parallel gates, one for each port. Others with a two-part central gate that expands as it tightens up. Others with a single central gate. Others with the "wedge". I'll admit that when I've had them in my hands, I never paid close attention to the inner walls of the valves, i.e. the part that would become the track for condensate when the valve is "stem horizontal".

Make me think of a great thread years back that included a digression on the difference between the innards of various valve types. (I could be wrong, but I think it included @Charlie from wmass, @EdTheHeaterMan, maybe @nicholas bonham-carter). One of those "I shoulda bookmarked that!" threads.

Thanks for your insight.
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  • Jamie Hall
    Jamie Hall Member Posts: 23,567
    Other than muttering that I wouldn't use a gate valve if I could possibly help it...

    The reason for setting it horizontal rather than stem up, in my view, would be to avoid having anything caught in the small space at the "bottom" of the gate track, where it needs to be able to slip in to seal and keeping it from closing all the way. Clearly, though, there is the possibility of crud getting into the "side" track and getting pushed into that space.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Charlie from wmass
    Charlie from wmass Member Posts: 4,331
    It's easier to pull gate horizontally when threads strip.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
    EBEBRATT-Ed Member Posts: 15,767
    You can put it in any position you want. Stem down is not recommended though.
  • SteamFTW
    SteamFTW Member Posts: 76

    ...Clearly, though, there is the possibility of crud getting into the "side" track and getting pushed into that space.

    I agree. That's a pretty big fly in what seemed like great ointment at first. There's no one answer to this, of course, but @Charlie from wmass's scenario--perfectly valid in itself--gave me an idea. His scenario isn't about preventing something from happening, like keeping out the crud. It's about that fact that *when things go wrong* you may be really glad the valve was oriented stem-horizontal. As in "do your work with concern for the 'next guy', if only because *you* might be the 'next guy'."

    So, you can't keep the crud out of a gate valve. But you can make it easier to get the crud out!

    With the valve installed stem-vertical, you have to fight gravity to get the crud up and out of the trough at the bottom and out the top of the valve. But with the valve on its side, as soon as you remove the gate, the crud--even if you have to break it up--has an unobstructed path out toward you. Squirt water in there and rinse it out. There's nothing in its way.

    I'm not disassembling a perfectly good gate valve to confirm this, but based on those detailed, shaded cutaway drawings in a Crane Catalog from the 1950s, it sure looks plausible to me.
    Fast. Cheap. Good.
    Pick any two.