Union Nut on One-Pipe Steam

jbmoff

Good morning,

So I realized after about a week of finally cold weather here in NJ that my boiler feeder was adding almost one gallon of water every two days to my system. Strangely, as I generally only add about 2 gallons MAX per heating season. So, I go off to play detective first before panicking about having a leak in the boiler! I find a second floor rad union nut had been leaking - A LOT. Last night, I turned the valve off as my heat was off for the night and today. The valve was replaced about 7 years ago, along with the riser to the valve (maybe a 15",1.25" piece of pipe) That riser had always been angled TOWARD the radiator making it difficult to pitch the end of the rad toward the valve. Not sure why.

Any way of possibly remedying this? I am going to tighten up the union this afternoon, etc. but you can clearly see the end of the radiator sitting almost 1/4" off the floor. We've had no issues with operating the radiator this way….

Thanks for your help as always!

ethicalpaul

Honestly I wouldn't worry about the pitch of the radiator unless you saw problems. All radiators hold some water in them between heating cycles. I've never disconnected a radiator without having water come out (I've only done about 6 but still—pros will tell me if I'm wrong about this). Make sure your supply valve there is fully open.

Have you put a level on top of the radiator to see what its actual pitch is? You can't use the floor as a comparison, it might not be level.

You might be able to get a plumber (or yourself) to fix the angle of the supply pipe, or it might be quite a challenge depending on the situation.

Problems to watch out for due to bad radiator pitch (and/or bad pitch of supply pipe horizontal below the floor):

• Banging
• Radiator vent spitting water or failing to close
• Maybe gurgling sounds
• Inability of radiator to heat up

One more note—the leak might be caused by the way you have tried to raise the far end of the radiator—the union is taking a lot of force from holding up the radiator like that…you might consider removing the shim on that end and adding whatever shims you need to add to make the radiator align with the valve.

delcrossv

Agree. The riser should not be supporting the weight of the radiator.

Jamie Hall

Tightening the union nut isn't going to help! Don't do it! You'll crack the nut and then you'll have a big job.

What needs to happen:

1. Disconnect the union, holding the riser in position.
2. Place shims under the legs of the radiator (probably have to do both ends) so that the spud on the radiator lines up exactly — left-right, up-down, angled) with the matching union on the valve.
3. Make sure the union faces are clean and smooth, but don't use anything harsh on them (nothing harsher than a nylon scrubbing sponge!). Some people advocate a smear of dish soap on the faces, but it shouldn't be necessary to add that — nor should pipe dope be used.
4. Make up the union by hand, and then tighten the nut no more than one half additional turn.
5. If it still doesn't seal, take it apart again. Double check the alignment and the condition of the faces.

jbmoff

The rad is pitched correctly (I used washers on the vent side). It's been so long since I did it…but without the washers, it is definitely pitched toward the vent, if I recall. And yes, I always pitch with a level. It heats great. Nice and slow. No water hammer. I have many vintage adjustable DOLE 1A vents (made in USA, baby) on my system that work effortlessly.

I think my biggest issue was/is that the riser has no movement vertically, which I found strange as most usually have a bit of play in them. Attaching the union nut to that riser had been difficult because of its rigid position. Thinking that may be why the thing was leaking so bad.

EdTheHeaterMan

Union Nut on One-Pipe Steam

The Steamfitters Union in the Philadelphia area, where grew up, had lots of Nuts working as both administration and rank and file members. Most of them were pretty harmless but nuts that became known as The Helpful Union Guys (THUGs) were the nuts you needed to be careful of.

Just saying. That is how it was back then!

jbmoff

@jamie:

Agree! I've done this a million times. Even changed the supply valve and spud myself on countless radiators.

BUT: the riser is ANGLED … maybe 4-5 degrees to the LEFT as you look at the radiator … making it difficult to line up the spud end/nut when you slide the radiator over to meet it. Best way to describe it is wanting to push the vent end of the radiator down into the floor 1/4 in in order to get it to line up.😰

Jamie Hall

Then the radiator is going to have to be angled as well, to match. A union isn't meant to, and cannot, compensate for ANY angular misalignment.

If it's less than an inch or so, it's not going to hurt anything to have the radiator off level.

ethicalpaul

OK yeah if there is no vertical play in the supply pipe I can see where that would be challenging.

But you have the far side shimmed up and I think if you remove or reduce those shims, you should have better luck aligning the radiator to the valve.

jbmoff

Well, I am going to give it a try without the washer shims on the far side. Going to be cold in NJ this week, so will give it a try later tonight.

Fingers crossed

jbmoff

So, I disconnected the union and definitely re-aligned the face to the valve. Boiler on. BUT… Unfortunately, it is still leaking and strangely enough, the valve is leaking quite a bit at the riser as well. Once the steam condenses, I can see the water dripping - A LOT - at the union and cascading down the riser into the floor.
Obviously, the valve needs to be removed. Anyone suggest replacing it completely or am I going down the wrong rabbit hole on this?

in all the years I have lived with steam heat, I have never faced the situation where the valve begins to leak at the riser, and I cannot get the union to lineup properly. Very weird.

ethicalpaul

I'm a little confused…it's leaking in two places? Or the leak at the union is just running down the valve and pipe?

Regardless, yes you can get a new valve which will include the "spud" (the part of the union that screws into the radiator) and the valve part.

The hardest part is getting the old spud out of the radiator, but there are several youtube videos showing how to do it.

jbmoff

Yes. Both places. 🤬 Just removed the valve. Will tape and pipe dope it and then see if I can line up the union again.

jbmoff

Talk about out of plumb

Jamie Hall

Tiresome. If that's the riser in question with the radiator out… there's no way a union is ever going to seal with the radiator even remotely level. Do you have any access to the piping below to get it at least remotely plumb?

Incidentally, I'd be kind of surprised if it had been installed originally that far out of plumb. Any idea what might have changed?

jbmoff

First, that riser is almost immovable. No play at all, which I’ve never come upon.
Second, I was able to re-tape/pipedope the valve. (No leak at riser now). My son and I wiggled that radiator as much as possible and I WAS able to line up the union pretty well. Nonetheless, I did find the valve is cracked under the union-hence the leak. 🥵. A large one, too.

When we moved in, the riser had a T valve which fed that radiator and another 1-1/4 inch pipe that ran in the opposite direction into the bathroom (through the wall) and fed that room. It was always out of plumb.
Crazy, right? It was capped when we moved in as the bathroom was remodeled with radiant heat.

EdTheHeaterMan

Depending on the fitting below the floor , that riser may be easy or hard to get it where you want it. It may be as easy as enlarging the opening and rotating the elbow below the floor (like the Left illustration). OR it may be difficult if the elbow is facing to the left or right and has a long run before the next fitting. (like the Right illustration) That one will mean that you need to do some major lifitng of pipes to get thet to pitch the correct way.

There should be something called a swing joint where there are 2 elbows within a few inches of each other that will allow for movement in all directions. Can you get to the underside of the floor? (like in a basement or crawl space) that way you can see what options you have.

delcrossv

https://forum.heatinghelp.com/discussion/comment/1819794#Comment_1819794

Or,you can put a street 90 into a regular ell and make your swing joint at the top of the riser. Get a straight radiator valve and you're done. Easy peasy.

jbmoff

I'm very familiar with swing joints. No way this set- up has one.

Unfortunately, I cannot get under the floor as it is a 2nd floor location, and my plaster ceiling in the dining room is in the way!

I did notice a significant crack in the valve last night - the union (after some jiggling and shimming of the rad feet) seemed actually ok. Ordered a new valve so we will see the results later today.

Thanks everyone for your insight!

delcrossv

Try my suggestion above, If you can handle having the rad 2" further from the wall.

Your valve cracked because it was handling a mechanical load- it shouldn't.

jbmoff

I am going to try the new valve this afternoon, along with being sure the rad is supported by shims/floor rather than the union/valve and go from there. Fingers crossed as I do not want the rad out from the wall 2 more inches with the new swing joints atop the riser… although it's a genius idea!!!😍

EdTheHeaterMan

Since you did have the old valve in place and that kind of straightened the vertical on that pipe, Lets assume that the elbow under the floor is turned the correct way. When the valve was removed from the radiator, the elbow shifted back to the position in the photo. If you can get something to cut that area of the floor so the pipe can actually turn to the true vertical position, the valve will fit better. If that works then you can make an oversized escutcheon that will cover the oversized opening in the floor.

ethicalpaul

I fear that joint, if there, won't swing. It is rusted in place. The whole pipe will flex that far and then return before the threads will give.

delcrossv

https://forum.heatinghelp.com/discussion/comment/1819900#Comment_1819900

Putting a street 45 on the end can get you back to your original wall spacing. Try the shims, but make sure the valve isn't supporting anything as you snug it up.

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1819908#Comment_1819908

You are probably correct Paul, but that section of floor is not helping. that pipe with the rusted threads nas to both bend and flex the way it stands now …and enlarging the hole can't hurt.

RTW

I respect all suggestions, but esp. Jamie Hall:

"

"What needs to happen:" etc

I too have single pipe steam system in a circa 1760 cape with, well, uneven floors. All that I would add (though I expect push back) is apply an ever- so -thin layer of pipe dope at the connection. I had all my cast iron radiators removed for paint removal and re-painted with ferrous metal paint years ago and used the ever -so -thin layer of pipe dope recommended by local family-owned plumbing shop and never looked back

just a suggestion by someone who loves steam heat

Regards,

RTW

RTW

P.S. I should add I only used pipe dope on the one problem radiator and none of the others that were properly aligned

Long Beach Ed

Did anyone else notice that the paint on that nipple indicates it is a modern replacement and not a 120-year-old piece of pipe? Check the paint and the mill marks. Something here has been messed with before.

mattmia2

Probably when the valve was replaced. If you're feeling lucky you can unscrew the nipple out of the floor and screw in another one. Probably when that was done it turned a couple joints in the floor and wall below and shifted the ell below the floor over.

jbmoff

Well… success! Without too much modification: valve was cracked. Bad. Yes, the nipple was replaced about 10 years ago but the original was that way, too. 😡

ethicalpaul

Nice. I assume the radiator is now pitched the wrong way. See how it does, you might get some hammer on start of heating, or you might not. Let us know!

If it does bang, try a very small vent on the radiator such as a MoM or Gorton #4

jbmoff

I did not put a level on it yet - have just been making sure there is no leak, which there is not.😎

Right now I am using a NOS Dole Verivent 1A from maybe 1959! Works like a charm.

Jamie Hall

If it's working, don't fix it…