Plumbing – this old plumbing fixture and can it go


I'm looking to do some DIY plumbing work, but this fixture confounds me. It looks like the biggest water hammer arrester, I've ever seen; but it can't be that simple. What is it, and what will I lose if I remove it?
What is this pipe for

Best Answer

I've never seen one of these (old ones) myself, but following Ed Beal's comment on a different question it's probably "an early form of damper as it was full of air" which could be as "large 2" pipe tee after the main valve with a stubbed leg verticle for 4-6 feet". A bit of googling can find similarly tall (and old looking) ones, although perhaps not quite as tall as yours (n.b., the one below was labeled "primitive"):

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