One Pipe System Wet Return - Can somebody advise ?

JasonFritz

I am trying to re-do my wet return for a one pipe boiler steam system and I wanted to route the wet return in a different way than the original configuration .
Looking for an advice if what I want is going to work or not ? Obviously I am not a heating professional
I will appreciate any advice . Thanks

ethicalpaul

Yes, it should be fine. The wet return is very forgiving. It can go up, down, all around, as long as it always remains below the waterline.

Of course, the shorter and straighter, the better. You can see my effort in this area here, with lots of good advice from the forum: https://forum.heatinghelp.com/discussion/178547/winter-return-repipe-project/p1

One really good piece of advice, which was also given to me on my thread above, is to make sure to plumb a Tee and valve at each end of the return, with 3/4" garden hose fittings on it so that you can flush out the wet return periodically (honestly like once every 5-10 years should be fine but you can do more with an easy hookup). Without the valves, it's basically impossible to flush it, and being a low point, it will collect gunk.

Try to send your drawing or photos and we can advise more. (Look for the "picture" icon at the top of the message editing area)

JasonFritz

well i want to put it above the waterline .....and only drop down in front of the boiler.

ethicalpaul

Do you mean "keep it above the water line" as in extend the dry part farther?

Or do you mean "have it below the waterline, then raise it above the waterline for awhile, then drop it back down later"?

I think we'll need to see the drawings

JasonFritz

i uploaded the drawing - it doesn't show up ? i see it on the post on my end .....

JUGHNE

Do you have only one drop from one main?
And where are your steam main vents?
What size are they?

JasonFritz

only one drop down towards the wet return in the end of the 2 inch main steam line . main line steam vent is a foot after the drop down to wet return.

ethicalpaul

I'm curious--why this change?

Also, why start the new dry section 28" lower from the main instead of starting at the height of the main at that point so you don't have to duck as much to get under it?

Jamie Hall

If -- and only if -- there is just that one drop from the steam main, you can raise it as shown -- though as @ethicalpaul says, why not just raise it all the way up to just below the existing steam main? If it's going to be above the water line, it doesn't matter how far above -- in fact, there is a great deal to be said for it's being all the way up, as that way it won't do evil things to the water level in the boiler, which it will if it's only slightly above the cold water level. For the typical boiler, running at a cutout of 1.5 psi, it should be at least 28 inches above the water line -- or solidly below it, but not in between.

JasonFritz

The pipes are running alongside the  wall and ceiling ( corner) of the house. There are windows under the 2 inch main steam line , so i want to put the return under the windows - that's why 28 inch. Plus i have " ledge" in the wall where pipes can "hide" and have a completly smooth and straight wall in front of them.  

JUGHNE

You are turning a wet return into a dry return.
Dry returns are to be sloped to drain just like a plumbing line.
The reason being that the air vents are often at the end of the dry return and the air will not pass thru any water pockets.
Also if steam travels thru that dry return and there are water pockets you may get water hammer.
Also any condensate sitting in a pipe will lead to deterioration such as you probably had in the old wet return.

Jamie Hall

I can almost guarantee that if you set that new pipe less than 28 inches above the boiler water line at it's lowest point you are going to have problems. You may find the boiler cuts off erratically on low water. You may find, if you have an automatic water feeder, that the boiler overfills. You may even find that you have the water hammer from Hell.

Steam heat is remarkably forgiving. Except for a few things, and one of them is that a dry return has to stay dry at all times, and a wet return has to stay wet at all times.

Do yourself a favour and do it right...

mattmia2

You could come out from the wall so it clears the space the windows need to open.

JUGHNE

Or go back to wet return laying on the floor near the wall.
You can lay it on bricks along the wall.
Works unless you have door way or wall to go thru.

JohnNY

Thank you for you using both "advise" and "advice" correctly.
So rare these days.

JUGHNE

John, how right you are! That would not have been noticed without you pointing it out.
Perhaps Erin will issue extra points for correct punctuation, spelling and grammar?

EBEBRATT-Ed

@JUGHNE

If we get graded on spelling and punctuation I have already flunked.

JUGHNE

No, I would never suggest that as there should be nothing to discourage anyone from posting anything.

I just notice the demise of the English language on the internet, texting and E-mails. To a certain extent, technology has done this to us as we rely on Spell Check etc. to cover for us.

The public school system has also allowed it to happen.

STEVEusaPA

EBEBRATT-Ed said:

@JUGHNE

If we get graded on spelling and punctuation I have already flunked.

If we get graded on spelling and punctuation I would have already flunked.

lol
Hey Ed it's the only thing I could ever correct. Leaving two pipe oil lines aside .

BobC

What I notice is the inability to string information together and devise a plausible answer without all the facts. They have a collection of facts ready to go but seem to lack the skills to interpolate between them.

I think some of educations decline can be laid at the doorstep of teaching to the test.

Bob

JasonFritz

From all the comments here I gather it is not a good idea to move the wet / make it dry / return to the middle of the wall . it was a preference but I am not married to it , so if it is a bad idea I will not do it and just leave the wet return on floor as it was.
Thanks for the thoughts and the time to write guys .

......i have to replace the original /corroded / pipe with new for the wet return , I had a old 1 inch copper wet return , that is sufficient ? should it be sloped towards the boiler and can it run a bit above the floor or it has to be laying down on the floor ?
Copper or black steel pipe is better for wet return ? i like steel because it's impossible to puncture :-) .....but the damn thing rusts ....... :-( .....so I guess copper ?

JasonFritz

This is the end of the main steam line 2 inch - going down to the wet return line - 1 inch . Should I leave the air valve in the same position or attach it higher to the horizontal part of the 2 inch main steam line ? I saw a video online suggesting putting 2 or even 3 main line vents for faster air evacuation ? and in case one fails ? crazy ? or a good idea?

Jamie Hall

That air vent is fine where it is -- but it's probably too small. The video you saw is correct -- although it is possible to overdo it in terms of money (not venting capacity -- but vents aren't free). How big (diameter) and long is the main that that vent serves? Then we can suggest what might work better.

On the wet return -- it can be copper or black iron; doesn't really matter (just not galvanized steel!). It doesn't have to slope -- so long as it is well below the boiler water line, you can run it pretty much as you please. I would suggest that you provide Ts with plugs or valves at the ends of the longer horizontal run, so you can flush it easily, though.

ethicalpaul

I just redid my wet return in black pipe because that's easier for me to work with and it's across a walkway so the strength was good for me. Yes it rusts, but it rusts slowly

nicholas bonham-carter

How high is the point of connection to the vent from the boiler waterline?
When the pressure in the boiler rises, the waterline of the wet return rises 1.75 inches per ounce of pressure. You don’t want that waterline to rise up to the point of connection, blocking the escaping air. In case of doubt, Make the connection as high as possible. You may need an antler of vents, if the main is long enough.—NBC

EBEBRATT-Ed

@nicholas bonham-carter
is correct about the vent location and @Jamie Hall is as well.

If the vent works ok where it is leave it be. Install new one(s) depending on how much pipe it is venting.

Technically, the correct location for the vent is higher on the horizontal pipe 18" away from the elbow where it turns down.

But if it works where it is and spits no water leave it alone

JasonFritz

Main line is a 2 inch pipe - 50 feet long . furnace is on one side of the basement. - straight run. -  Main line is pitched. 3.5 inches over 50 feet. vent on the other side . the pictures are the old vent - i don't think it was working that well, or at alll. 😕 wasn't hissing. And seems rusty. - since I re- did  the main line with new pipe it's easy enough to put 2-or -3 air vents in the horizontal end 18 inches away from the turn down to wet return. 
I don't think it adds expence to the project , T-s are like 10-15 bucks. I haven't checked the air vents but I'm sure they are not " hundreds" of $. 
I'm doing it for myself- so I'd rather make it work well. Winter is coming 😁😁😁😁

Point of connection of the OLD air vent -  7 foot basement. I would say it was 20 inches from the ceiling....84 - 20 = 64 inch. -(33 inch water line , furnace was on bricks. ) , so  31 inch above water line. 

New air vent i can put on the horizontal end of the main steam 2" pipe as high as 3 -4 inches below ceiling. (8 inch empty joist space above anyway) - so it will be 47 inches above water line. 😁

JasonFritz

dropping from main steam line 2 inch - vertical drop to wet return line - should I keep the 2 inch pipe for the portion "above " the water line - and then reduce 2 inch to 1 inch "below" the water line - and do the lower portion of the vertical pipe and the wet return all in 1 inch ?

old pipe was 2 inch(about 2 feet) - reduced to 1.5 inch ( about 3 feet) - reduced to 1 inch just on the floor level .

JasonFritz

Excited to finish the end portion and wet return , and post pictures so you guys can see if I f*cked up

ethicalpaul

My opinion is that you can reduce it immediately in that area. There is no steam getting delivered to radiators, it's just sitting there with no movement at all.

Just keep the reducers on vertical pipe only. Otherwise they trap sitting water in the main.

PS: What's the net sq ft or BTU rating of your boiler? Just curious how large it is.

JUGHNE

IIWM, I would put full flow ball valve when you start the 1" line.
Then below it add a tee for hose bib connection, 1/2" ball valve would be best.
Do the same on the other end.
Then you can isolate the wet return and flush water from either end without pushing sludge into the boiler or up into your steam main.
Use F X F hose for connecting, I use washer machine hoses.

JasonFritz

I have a 170 000 Crown bermuda boiler/ furnace
https://www.ecomfort.com/Crown-Boiler-Co.-BSI276ENPZZPSU/p24041.html

JasonFritz

Hi guys , another interesting question for the Pro-s :-)
I have a 1,1/4 inch gas supply to the furnace - that reduces to 3/4 inch - that enters the furnace as 1/2 inch nipple - what the heck ? Do i need such a large gas supply pipe ? Or i can just do the whole thing in 3/4 inch ?
No idea why it was done like that ...... they had leftover pipe ?

ethicalpaul

I’m not a pro but I’m awake 😃

Mine is 1” going to 3/4 going to 1/2. Part of it is because I used to have a gas water heater also coming off that 1”. Also my old boiler was larger BTU and who knows what the one before that was!

Gas pipe causes resistance to flow and there are charts showing what size pipe you need for various distances vs feed rate.

I only redid enough gas pipe to make a more direct route to my boiler. So I left the 1” in place but did cut it shorter because the old routing was crazy/lazy.

JasonFritz

Oh, i kind of understand doing the first 50 - 60 feet from the gas meter to the furnace with 1,1/4 inch. For resistance, flow, whatever. But the last 5 foot drop from ceiling in 1,1/4 and within a foot reducing to 3/4 to 1/2 inch? 
I think I'll just change the last 5 foot drop from ceiling to 3/4 with a 1/2 inch tee into furnace. Really dont want that thick 1, 1/4 inch pipe right in my face. 😁😁😁

mattmia2

You have to do the pressure loss calculations. The sizing was probably done with the most conservative method but unless you recalculate, you wouldn't know if that run can be smaller and still have adequate pressure at the flow that boiler requires. It also may have been sized for an older conversion burner or boiler that was less efficient or more oversized than the current boiler.

JasonFritz

Thank you " matmia2" . Does anybody has a link for  pressure loss calculator? 

STEAM DOCTOR

I would leave the larger gas. Might not be neccessary, but will help on low gas pressure days. In my part of the world, we have occasional low gas pressure days. When it's reallly cold, the gas infrastructure can be overloaded. Next time that gas pipe is in your face, just give it a kiss and thank it for being there for you. 

ethicalpaul

JasonFritz said:

Thank you " matmia2" . Does anybody has a link for  pressure loss calculator? 

The boiler install manuals all seem to have the tables in them, but listen to the @STEAM DOCTOR

mattmia2

That chart in most manuals is just an excerpt from most of a chapter of the fuel gas code that you have to work through to do it properly.

JasonFritz

The Crown Boiler Install manual ust says " refer to whatever number / chapter of the US gas code for pipe sizing" .....its very helpful they couldn't have just said ....you need whatever size ....or whatever gas pressure ....for this or that size boiler ?
both easy to measure :-) .......instead refer to a bunch of tables ,find which one applies to you first if you can .... I hate it when companies make it harder when not necessary ... :-)