Moving steam return in one pipe system…images in thread

steam1916

Hi, I have a return pipe in the middle of my basement that is head level but runs across entire width of home.

My plumber said he can remove that return and relocate it so goes around the perimeter snaking under the stairs along the wall and making a left against the front wall and back to the boiler.

Should I be concerned it will mess with the entire system or since it’s a return it’s not as big a deal as the other pipes to the various radiators.

looking for advice sorry no pictures.

mattmia2

If it is a return it can be rerouted fairly easily by someone that understands how steam works. You can't just move it anywhere, but the rules you need to follow give you a lot of flexibility. If you are moving it from above the water line to below the water line you need to make sure your new design still allows it to vent properly. Is this one pipe or two pipe?

steam1916

it’s a one pipe steam system!

What are the rules?

mattmia2

The simplest way to put it is to say the water has to get back to the boiler, the air has to be able to get out and the steam has to not be able to get anywhere it shouldn't be.

If you hire someone that understands steam that should be simple for them.

steam1916

additionally how hard is it to move the pipes upward higher into a cieling? Is that possible, and if not, why? Why can’t people just move them lol

mattmia2

If it is a return it has to be under where the steam condenses in the main and the emitters, the water can't flow up hill.

EBEBRATT-Ed

If you raise the pipe it will probably trap water and you will get water hammer. But we need pictures to tell for sure. Chances are if it could be raised the original installer would have done that

steam1916

ok attached the pictures!

mattmia2

That is a single dry return. If it were to drop to the floor and run along the floor to the boiler, it needs that vent that is at the boiler to be moved to where it drops to the floor.

The condensate that forms in the radiators and in the main itself runs toward the end of the main because it is all pitched that way then it follows that dry return below the main back to the boiler.

The air in the main also follows that dry return toward the vent at the boiler where it is vented out.

You might want to get "We Got Steam Heat" to learn the basics of how steam systems work.

steam1916

I am reading that. It’s not dropping to the floor, it’s only going to be waist high though around the wall…

ethicalpaul

Do you mean you plan to run it waist high? It's at head height now, right?

Waist high is not good. You don't want it near the boiler water line. Far above it, or far below it is what you want.

steam1916

well we’re gonna reroute it underneath stairs and around the perimeter but I guess it will all slope downward —- would that be sufficient??

Jamie Hall

Rules tend to be unhelpful, because there are too many exceptions… but…

First, the pipe carrying the steam to the radiators has to be pitched to allow the condensate which it also carries to drain. It can either pitch back to the boiler or away from it. But it has to pitch.

At its lowest point it has to connect to a pipe which will carry the condensate back to the boiler. In your case, that is the pipe which you want to move. That pipe can either be high, but lower than the pipe carrying steam, in which case it must pitch back toward the boiler where it can drop to the boiler, or it must be well below the water line of the boiler — preferably at or near floor level. If it is low, it doesn't need any pitch.

The air has to be able to escape freely from the pipes. That is called main venting. Where the main vent or vents is placed depends on how high that return pipe is.

steam1916

This is how he is going to run it, it’s all prepped but how do we feel about the location

Jamie Hall

Hmmm… that is the boiler over in the far corner? That will probably be OK, but ONLY, repeat ONLY, if the pipe has a definite slope of not less than 1 inch in 10 feet towards the boiler end. If it's set with any less slope, it will give you trouble.

I'd be much happier if it were set an inch or two above the floor level…

steam1916

why floor level??

ethicalpaul

Because you don't want it near the water line of the boiler

mattmia2

You want it to be filled with water so that steam can't get in to it and collide with the water and cause water hammer.

Why do you want it half way up the wall? Near the ceiling tucked over to follow the wall or anywhere near the floor would be fine.

steam1916

I don’t think it can go upwards where the stairs and wall are, I’ll ask if we can lower it

mattmia2

I see possibly 2 different dry returns in those pictures. Which one are you trying to move and what are you trying to accomplish by moving it?

steam1916

oh my. Those pipes are hot, I think one is the third floor and other is for the first

steam1916

which two?!

steam1916

we are try to gain the space where it ran across middle of room lol

mattmia2

I think sketching a rough floor plan would help. I thought this was one return

And this is another

But now I think yo might just be showing different segments of the same pipe.

You could bring the pipe around the perimeter near floor or ceiling level in the opposite direction and avoid the stairs altogether. If you do it at floor level you can use copper.

steam1916

The two pipes together is near the front of the house and the one you circled is in the middle. I don’t think we’re touching the two ganged together and to be honest I’m not sure it’s like that, but any information would be helpful

Jamie Hall

As @ethicalpaul said, floor level will give you much more reliable op0eration and many fewer headaches. Your intermediate height — while it may work with enough pitch on it — is just about the worst elevation it could be at.

steam1916

where do I find the boilers water line and how do I ensure I’m below it??

mattmia2

it is marked on the side and is approximately in the middle of the sight glass. you should be probably 6"+ below the bottom of the sight glass although if there is only one connection to that wet return the distance below is less critical

steam1916

yes my boiler is on a concrete platform but that newer black pipe looks like it’s almost parallel to the sight glass on the opposite side of the room lol

ethicalpaul

You can use a laser level to see just how close it is, but by putting it down at the floor you remove all doubt.

Keep in mind the water level in the boiler can vary over time and if it gets lower to just at or slightly below parts of the horizontal return, you can experience water hammer. It's not pleasant!

One of my "clients" had this scenario because in the old days boilers were much taller and their water lines higher, so their "waist level" return was OK a hundred years ago but with their new boiler they had hammer. They found they could raise the water level and keep it high and it would run silently.

mattmia2

https://forum.heatinghelp.com/discussion/comment/1869849#Comment_1869849

usually that only becomes a problem if there are 2 or more drips in to that wet return. if there are 2 returns above the water line the steam can come in one drip and the air can get out another drip to the vent so steam can get down to the water level and hammer. if there is only one drop to the wet return the riser tends to stay full of air and steam doesn't contact the water. unless it is so high above the water line that the boiler end is partly open and steam can get in that way.

steam1916

but regardless tell the plumber to move to closer to the floor? Or sloped??

steam1916

@mattmia2
So I measured this morning the waterline is around 34 inches and the new pipe is around the same off the floor, given the floor is not level but my laser was dead.

I have reached to my plumber and let’s see what he says

steam1916

@mattmia2 and you may be right there are two returns?? I noticed two vents here in the pictures where it loops back

mattmia2

I can't tell what connects to this pipe:

steam1916

they both connect below into the same pipe

mattmia2

What connects to it from above?

steam1916

@mattmia2 one has a vent gauge thing and another has a vent gauge thing.

steam1916

it’s something like this I guess lol

mattmia2

https://forum.heatinghelp.com/discussion/comment/1869934#Comment_1869934

it has to have another pipe connecting to it above the water line for there to be something for it to vent. That doesn't mean that someone that didn't know what they were doing didn't stick a vent on it. You may want to find a steam expert unless you want to learn yourself and micromanage the plumber(or they should find one or look at what we said if they are open to learning.)

ethicalpaul

It's kinda hard to see in the photo, but that's a reducing tee at the top with the other main coming into it, I think. Crusty!