Funny stack of connectors for radiator vent

espire

Hi all, I've learned a lot from reading some posts here, but never asked a question before.

We recently moved into a 1930s Long Island steam-heated home. The system wasn't in great shape but it works and we are working on fixing things up one by one.

I'm replacing the old and seemingly stuck Varivalves with new Maid-o-Mists, and found an interesting set of connectors for the vent on one copper-fin radiator. It seems plausible to me that this was meant to be a main vent, as the lower pipes are pretty big, and moreover, this radiator might be the last one on this line.



If I wanted to put a main vent here, how many pieces should I remove? Or, to make things easier, could I just replace the existing vent with a 1/8" vent with a large enough opening?

This also makes me wonder in general, if you put a wide vent on the last radiator in a line, is that often sufficient for main venting?

Thanks

leonz

My being a novice about this tells me that the piping was done in this way because there was not enough room to install a round vent that they had on hand at the time because of the radiator cover itself being so close to the piping and not allowing a larger round steam vent to fit in a vertical position.

If the existing vent works you could either replace it with a new one or leave it.

neilc

looks like condensate is/was getting up to that vent,
is that fintube pitching up towards the vent? drastically?
post a picture of that fintube, end to end to show pitch,
and,
too fast of a vent will hold condensate up in there, even with pitch,
vent your rads and fintube SLOW, and vent your main(s), agressively,

the main venting you speak of should be down in the basement , on the Main(s),

how's the boiler and near boiler piping?
post a picture or 2, floor to ceiling, showing controls, sightglass, your header,

espire

Thank you for your insight @leonz! I'm not sure if the vent was working too well -- it may just be a big room with a small copper radiator that won't work well until the steam is on consistently -- but I replaced it with a fresh one:



@neilc, thank you for the observations and offer to help more! For now I just snapped some photos of the radiator in question. The main leading to this part of the house runs into a creepy narrow space between the foundation and finished walls of the basement so I'll have to save that for another time.




It looks to me like there is a very slight incline which could probably be steeper. I'm not 100% sure if the tilt is so easily adjustable though.

ethicalpaul

that vent might not work well (might remain open in the presence of steam) tilted like that. If that occurs (if you see steam coming out) you might have to remove some of those fittings to get it a little lower so you can make it be straight up.

To clarify, the tilt of the radiator itself is fine, but the vent should be pointing straight up

Dan_NJ

To get some clearance there you could remove the coupling, or the stuff above the bushing in that coupling, put a street 90 right into the bushing there and get enough height for your vent to be upright. I don't like the tilt. You have more stuff in there than needed.

espire

Thanks @ethicalpaul and @Dan_NJ!

Dan unfortunately I'm not so familiar with the pipe terms. I think what you mean is, remove everything above the F-F 1/2" (I think it's 1/2) coupling, put a 1/2" M-F 90º in, and then reuse the existing M-F 1/2"-1/8" on that so I can put the vent on?

Alternatively it should be possible to remove the tall M-M segment and it's F-F coupler and plug the rest on top of that to reduce the height, right? Then I wouldn't need to get any new parts. Though, it looks like these pieces will not easily come apart.


FWIW, the vent is operating correctly for now.

Dan_NJ

Well if the vent is working and stays that way, go with what works I guess? I was thinking into that bushing, assuming it all comes apart, would accept a street 90 M-F and you could extend horizontally off of that.
Edit: Of course you could also try a new Varivalve in there, if for no other reason you know it will fit more or less, and it's heating season
https://www.supplyhouse.com/Bluefin-BLES025-1-4-Black-90-Street-Elbow

espire

Now that I look at that stack again, I wonder why they didn't just use a straight Varivalve instead of an elbow...

I found another radiator with the same clearance issue but no stack of adapter pipes, so I'll have to get a couple of backups that fit, either Varivalves or 41-Ms or otherwise.

Thanks all again for your advice.

mattmia2

I'm sure it originally had a straight valve with a 1/2" thread, that is where the additional fittings came from.

TwoTones

Good job getting rid of vari-valve, they are nothing but trouble.  30 percent of them have a defect that causes them to lock up and not vent.  When they do work, they vent way too aggressively….