Two Pipe Steam - Air Vents and some other confusion

Dnogu860

So I've owned my home for almost 2 years now and it has a 2 pipe steam systems. The system works Ok but just is not right. The heat is inconsistent throughout the house and nine of the radiators seem to heat up at the same time. It is more like they heat up in the same order every time and certain rooms only get consistent heat on colder days.



First is the main air vent. It does not exist. I have followed the lines to the end of the main steam lines and it does not exist. There is something else there that looks more like a thermostatic trap. By the end of the return line it appears like the main air vent should be there. Not sure. I have also been through the entire basement and there is not any f&t traps.



I am wondering if that is were the main vent should be in and if it is necessary with my set up. All of my questions came about after reading "We've Got Steam Heat" and thought it is extremely helpful I'm also confused about different stuff now.

Rod

Two Pipe Steam.

Hi - I labeled your pictures . What are "A" and "B" ?  Where does "C" lead?  The way the piping to the "trap" is configured it might pass air and close for steam but doesn't look like it would pass condensate (water)

In the other picture,where do "X" and "Y"  lead back to? Where do the pipes leading downward from "X" & "Y" lead?  I've attached a generic drawing of possible two pipe steam mains and returns layout. Note the absence of a  drip line when a cross over trap is used.

It might help if you posted some pictures of your your boiler. Take them from back away so we can see the piping connected to the boiler and that of the mains and returns.

- Rod

Dave in QCA

Looks a little like an old Dunham system

The thing that looks like a radiator trap, may actually be one. If so, it should work pretty good unless it has failed. Dunham in the early years used and air service valve, essentially a Paul type valve and the capacity was not as good as is needed for good main venting. Anyway, this serves as the main vent on your steam main. It looks to me like the steam main is the larger pipe, and the condensate return is the somewhat smaller pipe that is just a little higher. This is a perfectly good way to vent your mains. It works very good. I am guessing that this point is distant from the boiler and the pipe that drops out of site is a drip for the steam main and it goes below the water line and back to the boiler.



The second picture is a little confusing, but it looks to me like the top of the return stack, where the condensate return lines drop and return to the boiler. Is there a vent of any type, or anything where you hear air escape from the return piping? I am guessing that you may not! Actually, if that is the case, I have seen a system cobbled nearly the same way. That small black iron pipe with the cap looks very much like the way Dunham connected to the top part of the Dunham Air Eliminator, which was their system vent device. All air, from the steam main and radiators are vented at a central point off of the condensate return lines.



I have attached a file that shows such a system except that the end of steam main is looped around so that it ends close to the boiler. It could be far away just as well. You will also see the Air Eliminator.



If your system is looking like this and my guesses are correct, you could run a test by simply removing the cap on the 1/2" black iron nipple. Then run the system and see if air comes out of that point. As long as your pressure stays low, i.e., controlled by a vaporstat at around 8 oz, and as long as all of your traps are in working order, you really don't need anything on that pipe. However, since you don't know if your radiator traps are working or your crossover trap. And, since I don't know if you have accurate low pressure control... It might be wise to install a Main vent devise at that point. It will close if water OR steam comes in contact with it. I would recommend a Gorton #2.



That will get you started on balancing your system. If my guessing is all correct, and you make the changes I have suggested, and you still have uneven heat, there are a few other things that can be done. It IS VERY POSSIBLE to get your system balance and you will have nice even smooth heat.



Please give us pictures as Rod has asked. We really need to see more to know what is going on.

Jamie Hall

Almost certainly

a vapour system which has -- no surprise -- been cobbled, as Dave says.  That thingy between the return and the main is a crossover trap, and is usually just a radiator trap.  Since there should be a drip on the main, there is no need for it to pass anything but air.



Like any other trap, though, they can fail.  It should be checked to be sure it is operating properly.



If it isn't working, or you are not sure, your best bet would be to replace it with a regular radiator trap or, even better, if you can determine the exact make and model you may find that the working innards are available and you can just replace them.



As Dave further notes, a main vent would be near the boiler -- and a Gorton #2 at that location would be the way to start.

Dnogu860

Two Pipe Steam

"A" is a dry return line next to the end of the main steam pipe. "B" is the end of the main steam pipe. "C" goes down to a some pipes that I assume are a wet return.



"X" is the return line that runs back down into the loop of pipes. "Y" also runs to the same place. "Y" is actually the water fill pipe.



I've attached to more photos of the back of the boiler and piping above. Let me know if there is anything other pictures needed.

Dnogu860

Two Pipe Steam

Thanks for all your help. I will definitely put the Gordon #2 at the end of the black pipe. Is there a specific trap that would work best for the radiators.



Thanks for all your help.

Unknown

your boiler

First of all.. your boiler is 100 percent piped wrong

Dnogu860

Two Pipe Steam - Air Vents and some other confusion

This I figured. I knew it seemed off when there was copper and solder. I also am posting this picture because it seems odd that the return line drops into the Hartford Loop. Do you have any specifics. I looked on the website for somebody that does steam work in the Lehigh Valley in PA but I can not find anybody that specializes in steam.

Dave in QCA

WOW

All I can say is that with so many things done completely wrong, at least they piped it in copper! That will make it easy to cut and remove! I don't know if I have ever seen a boiler that had some many things done completely wrong! I am amazed that you get any heat out of it at all.



You really need to contact a good steam pro that knows what he's doing and have this thing straightened out.

Dnogu860

Two Pipe Steam - Air Vents and some other confusion

Where can I look to find reputable steam specialists in my area? I found tons of plumbers and HVAC companies but non that really focus or seem to even really understand steam?

Steamhead

Look closely at those copper fittings

they look like DWV fittings, for soil piping!



There is also a short-circuit between the steam side and the return side, so putting a main vent there won't help much- the steam will jump over and close it.



This is a classic example of "you can't fix stupid". The boiler manufacturer includes a piping diagram and all you have to do is follow it.



What part of Lehigh Valley are you in?

Dnogu860

Two Pipe Steam - Air Vents and some other confusion

Allentown, PA. (the west end)



I've been staring at this for a while. If you seperated the steam side and the return side (which is also where the water feed is, could you just repipe the return and feed into the wet return before the Hartford Loop?



Thanks again for all your help.

Bio

Steam guy

You can try Jstar at ecuacool, he's in NJ but covers some PA also  732-494-HELP.

JStar

Steam

Wow. Those pictures are incredibly hard to look at. It reminds me of pictures of boilers that exploded; pipes everywhere, no rhyme or reason at all.



I certainly do service Allentown. I'd be happy to offer an estimate. You can call or write any time.

732-494-HELP

j.starosielec@ecuacool.com

Steamhead

"And we're living here in Allentown"......

That would help, but there's so much else wrong with that installation it's best to just start over.



Definitely get JStar to work on it. He knows his steam!

JStar

UPDATE

So, we repiped the boiler and made some system upgrades such as new cross-over traps, and inlet orifices in all of the radiators. New Vaporstat running at 10oz or less. System hovers right round 6 oz.

JStar

System

Also of note...all of the cross-over traps were failed closed. The original radiator traps were looking very beat up as well. I couldn't believe this system ever worked in any capacity. When we were done, every radiator was hot within minutes of the boiler making steam.

Steamhead

That's beautiful work

with great results! Well done!

Dave in QCA

Great Job

As always, very nice job, Joe. I have also seen that Dunham traps tend to fail closed, but sometimes, a radiator trap can be open and won't close. I think it is because the thermostatic element comes apart allowing the the disc to lay on the seat. Sometimes the cycle might cause it to be moved to the side, allowing air and steam to pass.



The old crossover traps looked like they might be Dunham Air Service valves. They were often used as crossovers. I found a couple on my 2 indirects, and they too were failed closed.

JStar

Dunham

They were indeed the Air Valves from Dunham (and one Hoffman). After seeing about 50 different replacement options for the elements, I opted to just replace the whole trap.

SWEI

De-knuckleheading vapor systems

seems to require a bit of creativity, but the results are clearly worth it.



I'll ask again -- is there any reason some of this ingenuity could not be applied to a conventional two-pipe system (using currently available parts) to produce a kind of modern "vapor retrofit"?