messed up two pipe, see pic

GW

hello, I posted earlier, but after going back I made more notes. I appear to have a goofy two-pipe. the system supply leaves the boiler (near boiler piping is wrong), goes to a tee that splits the main, roughly 50/50. (if I re-pipe, I will get two supplys off the header).



the two supply mains meet together, basically connecting, basically creating one giant main, although both mains are pitching down to where they meet, yet there is a tee where they meet that drops down at 45 deg. and then there is a 1 1/4" main (dry return) that goes back to a F&T. There is no vent on this at all. nothing.



Then the rads create their own return system, each rad has a thermostatic trap. The two mains trace back the same route as the supply mains and come together in a bullhead fashion and the branch comes out where there is a main vent, then drops down into the boiler return water.



After some evening reading in the good steam book I wonder if I should have two f&t traps at the end of the two supply mains, and run two separate returns back, venting each return back at the boiler.



any comments would be appreciated. Thanks, Gary

GW

ahh my pic got lost

I will try to post

GW

pic

OK, so I can't seem to load up my drawing of the steam piping, so let me explain it- the f/t trap has no vent, and it just handles the condensate from the two supply mains that meet at the other side of the basement.



The abused main vent you see is the return system for all the rads in the house. You can see the f/t trap to the left/rear.



Anyway, should I de-couple the two supply mains and install two f/t traps at the end of the supply mains, and then run two new dry returns back to the boiler?



Thanks, this one has me scratching my head, Gary

GW

drawing

Ok it works with jpeg, I am new at posting my home made drawings. Anyway, you can sort of see with my crude drawing that the f&t only handles the drip/return from where the two supply mains meet up. the radiator return systems pipe back to the boiler, meet up, and use a normal #77 vent.



I did not draw the hartford loop, it is there.



The near boiler piping is messed up, and if I re-pipe this beast I will want to have two supplys off of the steam header.



Thanks for any comments, I am not a two-pipe guy, trying to get the basics down



Gary

Steamhead

Well, it's definitely knuckleheaded

see the plugged tee on the dry return just below the air vent? That's where the return from the steam mains connected to it.



Each steam main will need its own F&T, but you don't need one that big- 3/4" will work fine. Both F&Ts can feed into the existing dry return that goes back to the boiler area. If more venting is needed on the steam mains, you can add main vents before the F&Ts.  And use a large vent such as a Gorton #2 on the dry return.

GW

ok

thanks Steamhead, I bet you've seen some winners. One problem though is the radiator returns travel back to the boiler at the same height as the supply main. Am I dead in the water? My impression is at this point I need two f/t and tie back onto the existing returns, and I should get rid of the solo "drip return". My concern is if I get two new f/t traps, I am going to need to drop the entire (2) return systems



Yes, that plugged tee...you are right it seems like the original piping connected the 'drip return' where the plug is, but at some point 20 or 30 years ago the f/t was added, and possible guesses as to why there was never a f/t to begin with?



How can this system work when it was built back in the day? It seems like the 'drip return' was cut in and added, and your observation about the plugged tee seems to indicate that the f/t was added too.



Thanks, Gary

Jamie Hall

I see...

that you've gotten Steamhead interested in this one -- good!  Best thing you could have done.



I do have a comment, though.  Is there any sign that there might have been, once upon a time, crossover traps from the ends of the steam mains into the dry returns?  They would have (most likely) been on a T with the leg going up from the steam main, then a nipple going over to the inlet of the trap (a thermostatic trap, like a radiator), then the outlet of the trap going down to the dry return -- probably into the leg of a T.  That was not an uncommon set up.  The crossover traps handled venting the air out of the steam mains and into the dry returns, where it would have returned to the boiler and that number 77 that's there.  Then that 45 down would not have handled the air -- just any condensate that found its way to that point.  That arrangement would have had the mains and the dry returns at just about the same elevation; no need to have the dry return lower, as you aren't trying to get condensate over into the dry returns -- just the air.



Which way do the mains and the returns pitch?  Towards the boiler?  Or towards the junction? 



Seems to me that if you left the piping pretty much as is, but added the crossover traps (or trap, if you don't split the steam main) the thing would work OK.  That 45 degree down and over with its F&T would act like a rather convoluted wet return...  Might not even need the F&T on it, but it probably does no harm (assuming it's working...).

Steamhead

Tie both new F&T traps

into the beginning of your existing drip return assuming you can get enough pitch. Connect the other end of the drip return to the plugged tee.



Also what Jamie said about the system having had crossover thermostatic traps originally.

GW

thanks, i am still not sure

Steamhead, thanks, i am not clear about the existing dry returns...right now they each back track the supply main and are teed together, and use a typical main vent. What I am not clear on is this OK?



Also, is there a general recommended f/t that you recommend? The grand total edr is 467. So I need two small f/t's? Do I simply use a two concentric couplings to reduce down to whatever size trap I end up using?



Thanks for helping me with my novice questions. gary

GW

pipe

Jamie, I will post a pic, it's hard to see based on the angle i took the pic at, but the two 2" mains come together with a couple of 90 deg elbows (makes sense right--after all they both are pitching down towards each other) So, you can not see the two 90s in the pic, they are hiding behind the drip return.



You will see a nip/cap sticking up out of the drip return. I am not sure if this ever served a purpose. However, it seems to me that the return system from the rads in original and there is no sign that they used connect to the drip return. Of course it is possible that it was changed several decades ago, but it looks original to me, meaning the rad return system never connected to the 'drip' return system.



I am still hung up on when the traps are needed and when they aren't. To re-pipe the radiator return piping would be a lot of work, so- is it OK that they run back to the boiler and use a 77 vent? I realize the piping is lame the way it is now, that could be changed.



Thanks, Gary

Jamie Hall

Let's see where we are here...

First, I presume that the dry returns pitch back to the boiler area and that smaller vent, and then drop into the wet return and the boiler?  Even though they are at about the same elevation as the steam mains?  And you say the steam mains pitch towards that funky drip return.



OK -- we're not that badly off at all.  Shouldn't need a whole lot to get it really singing nicely.



The dry returns, if my supposition above is correct, are fine as they are, except that I would want to replace that 77 with a Gorton #2.  Those returns carry the condensate from the radiators, and also the air vented out of the radiators.  Assuming all the radiator traps are working, there should never be any steam in those dry returns.



Now the steam mains pitch towards that funky drip.  It is really valuable to get air out of those mains as fast as possible, but the only way air can get out now is through the radiators -- not such a good idea.  So you need vents on those mains.  If you split them so they don't join (probably not a bad idea), then you need one good big vent at the end of each one.  That will get the air out of them.  But you also have condensate in those steam mains which you need to get rid of.  Several ways to do that, but given the setup you have I would use two F&Ts and connect them both to that existing funky return -- and I would take the existing F&T off that return, and just have it drop directly into the wet return and the boiler.  I would put a vent on that line just about where it turns down to go to the boiler.



As Steamhead said, if you had the elevation difference, you could hook the F&Ts from the steam mains into the dry returns -- but as I understand it, you don't have the elevation difference.

GW

yes

That is it Jamie.



Is it true that the current returns can basically stay as they are now? Of course i would want to drop each return into the boiler return header independently and put the vents where they belong. I am just perplexed (being a newbie to 2 pipe) because I don't run across many air vents in the good steam book. Is is because the return system is totally seperated from the supply system?



I would use two new f&t's? Do I just concentric coupling down to smaller f/t traps?



Thanks,Gary

Steamhead

Is there a way

to drain the ends of the two steam mains individually into a WET return and run that back to the boiler? Then you could completely abandon the drip serving the two mains and vent them with the usual main vents. The dry returns from the rads would still need to be vented, and yes the 77 vent is too small for that. However, it's perfectly fine for a pair of dry returns to join above the waterline- that way you only need one vent.

GW

sort of hard

If I created a wet return the home owner would need to step over the pipe; I could say it would be the best method- but if I just dry run it back do i really lose much?



I just spoke with someone at B&J, I wish i jotted his name down because he was super, he indicated this was likely a vapor system. At the time I didn't know the date of the house being built- I guessed 1930. After that I called the HO and asked, the answer was 1920.



He said two f&t's may be overkill, that one VT-1 would do the job. I just want to get this thing right once and for all. he also commented that the pressuretrol needs to go bye bye.



Gary

Jamie Hall

Seems to me...

like we're getting somewhere here!  First, as Steamhead notes, there is no reason to split the dry returns and drop them separately.  Just swap out that 77 for a Gorton #2, and you should be good to go on the dry returns.



I kind of figured there was a good reason for the funky overheard drip from the steam mains, though, and there's no good reason to pull it out.  As I think about it, the only real reason to split the steam mains is to establish a definite end to each one -- where you will need a vent (one for each).  Otherwise, if one simply puts a vent at the location of the drip, one really can't be sure that that is really the "end" of the line.  I'm not sure whether that is really necessary, though, or not.  So...  what I would do, if it were my headache, is put a pair of good vents at that junction.  From the photo of the junction, you just might be able to use that odd nipple and cap you mentioned as the start of an antler to hold them -- then you wouldn't have to disturb the mains piping.  Your guy at B&J is right -- if you do that, then you really only need one F&T going into that line, not two.  And 3/4" is big enough (in fact, you don't want to go too big on an F&T -- they wear out faster if they are oversized.  I'd put it right after that new main vent place, more or less instead of the 45 degree down section.



I would rather see eccentric reducers, flat side down, than concentrics.  You are trying to get rid of water flowing on the bottom of the pipe, and a concentric would retain water behind it, which could conceivably present a water hammer hazard.



This probably was a vapour system, from the look of it.



Vents can be a little confusing, but not if you really think about what you are trying to do: provide a way for the air to get out of a pipe, while steam goes in the other end.  Originally, vapour systems often had only one vent, at the boiler, where the dry returns joined and dropped to the boiler.  Some vented the steam mains through traps into the dry returns; others also had vents on the steam mains at the ends (as we are suggesting).  It (or they) didn't need to be big, because the coal fire started slowly, so they didn't have to vent rapidly.  Nowadays, we have oil or gas which goes from zero to whatever in no time at all, and we need to have bigger vents to get rid of the air faster.



Your B&J guy is also right about the pressuretrol -- you'll want a vapourstat instead, and I would bet that this system will run just fine with a 12 ounce or so cutout, and 4 ounce cutin (you'll want to keep one pressuretrol as a high limit backup, in case something happens to the vapourstat -- I'd use a manual reset one, set at 5 pounds, were I to do it).



Hang in there!

GW

yes

Jamie, yes, I am getting there, gonna lay out a plan for the ho tomorrow. Here is a pic of the supply header, note the "between the uprights" supply, tsk tsk, I will get the Ridgid 200 singing soon.

Steamhead

The reason for two F&T traps

is that if each steam main has its own F&T, steam cannot cross over from one main to the other and possibly affect steam distribution. This is the same reason we would drip both mains individually into a wet return, if we went that way.



I'd still look for a way to do a wet return, maybe by running it along the wall in some manner. That would involve the fewest moving parts.

GW

ok

As far as my trying to de-code this system, I think my brain is starting to catch on with the way it is now. Although not ideal by any means, it is 'sort of' working because the supplys can be treated as a one-pipe because the return system is completely separate. I so badly think the system won't work w/o a proper f&t (or two to be more ideal), but that is because a normal two pipe is sharing the drip at the end of the return with the radiator return system.



What I still can not get is the fact that the current f&t  isn't vented, so is this 'drop main' even venting at all? I suppose the condensate water may lift the float and get on back to the boiler, but air isn't going to pass through right?



Thermostatic traps- B&J guy says I am likely getting some bypass when the pressuretrol is sending too much pressure in the supply mains. With a vapourstat the old thermostatic traps will perform a bit better. He says the minor amount of bypass will not be an issue with lower pressures.



In all actuality the rads get fully heated.



One mystery I still haven't solved in my mind is how the boiler managed to lose its water, one of the main complaints is the ho has been seeing the boiler over fill itself, even though a few years ago a time delay was installed on the old feeder (which made the problem go away for a few years...now the problem is back).



I did notice two rads were shut off the other day. This boiler is already a little large, so i wonder if two rads being shut off had anything to do with the missing water (well, not "missing", you know what I mean, it temporarily migrated out to the system.



Thanks for all the comments!