Uneven heating in two mains - incorrect piping? i posted pics - please help!

sean_b

Hello all, I have a question about how my new steam system is piped

and if it might be the cause of some of the problems I am having with

it.  I am completely new to steam heat but have been coming to this site

for a couple months now and have learned a ton! It has been an

invaluable resource!Sorry for the long post, but I figured more

information the better - I hope someone might be able to point me in the

right direction - this has been a seemingly endless process of trial

and error chasing down the issues with this system.  Very frustrating.





I put up a couple pics showing how the new boiler is piped.  A

little background is that the old burnham boiler died and had to be

replaced.  The heating co. basically put in a new smith series 8

3-section boiler to replace the old using all existing piping as much as

possible I think.  Basically the main problem I am having right now is

very uneven heat from the radiators in the rear of the house vs the

front of the house.  The rear rads take forever to heat up, and the

front rads all heat very fast (minutes).  You can see that there are two

mains.  The steam comes out of the riser, makes a couple 90 deg turns

and then hits a riser to a main that I call the front main (all

radiators on the front of the house are fed from this main).  It then

travels a bit further maybe 12 to 18 inches or so then hits the second

riser that goes to the rear main which feeds all radiators on the rear

of the house.  Both mains seem to vent well and heat up fast - the front

main does heat up faster for sure but the rear main is only a couple

mins behind it seems.  though maybe not quite as hot.  Remember the

steam hits the front main first.  Also all of the front rads heat up

super fast even the second floor rads.  but it takes quite a while

longer for the rear house radiators to heat up, especially the second

floor ones - takes forever! Most all of the time the second floor rear

house radiator (the furthest possible radiator) never heating up at all

unless the system has run for a long time like 40 min+. By the way, all

radiators have brand new ventrite adjustable vents, and the mains have

brand new ventrite vents.  It is a single pipe system, condensate going

in direction of steam.  All mains and exposed supply pipes and even the

returns are now insulated.  





Also, the radiator vents seem to vent very hard.  The fronts make a

lot of sound with air very rapidly exiting (they are mostly closed down

to 5 or less). The rear rads vent even worse - many making loud and

very uneven whistling sounds almost like uneven panting  or

something.  But seems like a lot of air pressure coming out at times

though not all the time (weird I know - dont know how else to explain

it).  All rear radiator vents are wide open as far as possible in an

attempt to get them to heat faster.  The front rads heat up and vents

close fast.  There was a water issue in that rear main (caused by a

contractor who unknowingly caused a change in the pitch of that rear

main) but heating guys have since fixed pitch, I have pitched suspect

rads more (that I thought might be retaining water), and there is no

longer any water hammer at all and I don't really hear gurgling per se.

like i did at one point (when the pitch of the main was messed up).

Also, i have never witnessed the pressure go past 1.5psi so I think it

is set correctly.





My biggest question is could the cause of the long time it takes to

heat up the rear radiators be caused by the fact that the steam hits

the front main first, then makes its way to the rear main? I.e. Is the

front main robbing the rear main of steam?  Is this the proper way to

pipe the two mains? It probably is as it was like that before....  But

we had a contractor (not a heating contractor - a building contractor)

tell us it is wrong - the main riser should go to a header that is a T

with one main going left, and the other to the right and the steam would

hit both at the same time.  To me, at first this made sense but then if

you figure the steam going up the main riser at a certain speed and

pressure, will suddenly have that speed and pressure cut in half - dont

know but maybe that could create a vaccuum or something.  





My second question is what to make of the uneven and loud and rapid venting of radiator vents?





Thank you in advance for any help or advice you have.  Anything

will help.  I feel like I have been chasing one problem after another

for the last three months and wasting a lot of fuel oil in the

process...





-Sean

Dave in QCA

Piping Looks OK

I can't tell from the pictures what size the header piping on the boiler is, and whether it is what the manufacturer requires, but I don't see any reducing bushings, and that is a good thing.  The orientation of the piping, and the way it is connected to your building piping, and to the equalizer and return, is correctly done.



The problems you describe sound like venting issues.  I assume that this is a one-pipe system.  You have 2 mains.  Do they have main vents on them?  If so, what type?  Are they working?  (Do they get hot?  How long does that take after the boiler begins to make steam?  Do they close, or do they continue to hiss and blow out steam?)

For your radiator vents, what type do you have?  Are they all the same, if not, list them all out.



The general advice for good and even steam distribution is that your mains should be vented FAST and Completely.  Your radiators should be vented slow.  It takes the combination of both of these things to get even steam distribution.  When you get even steam, you will love it!

TomM

...

not sure what the cfm's are on the vents you have, but remember, 'it's all in the venting'.



and this guy's wrong:   we had a contractor (not a heating contractor - a building contractor) tell us it is wrong - the main riser should go to a header that is a T

with one main going left, and the other to the right and the steam would

hit both at the same time

venting rates will determine where the steam wants to go, not the configuration of the piping. 

sean_b

re: Piping Looks OK

Thanks Dave. 



It is a 1-pipe system both mains have vents located about 20 inches back from the end of the returns (just before the do a 90 deg turn and head down to go back into the system).  The mains do vent and do get hot and close.  The front main as I mentioned vents very fast and closes within minutes.  The rear vent (the one that is second in line so to say) also vents pretty well, just not quite as fast but it does get hot and the vent does seem to close on it a few minutes after the front main does.



All radiator vents and the two main vents are all brand new and went in with the new boiler at the end of November.  All vents are "Vent-Rite".  The mains are big unadjustable ones, and the rads have smaller adjustable vents (1-8) and are all the same.   Like I mentioned the front radiators I currently have closed the vents down to vent mroe slowly as they work so well - at about 4-5 for each.  4 or below hey dont seem to work well.  The rear mains I have wide open just to try and get them to heat quicker.



Any ideas what could be causing the venting issues?  that is my suspicion also that maybe water in the main but then we get no water hammer so then i thought maybe the piping configuration might contribute to the slowness..

Rod

Main Vents

Hi-  I think the first thing I would do is dramatically increase my main venting. You mentioned that you are using Ventrites for main vents. Ventrite makes two main vents the 35 and the 77. You didn't mention which one you are using so I included info for both. Both are rather on the small side venting capacity wise.Here is a comparison of main vents venting at 1 oz. of pressure: (This info is from Gerry Gill's excellant venting book available in the Shop section of this website)

Ventrite  35         .110 cu.ft per min.

Ventrite 77          .190 cu ft per min.

Gorton # 1          .333 cu ft per min

Gorton # 2         1.100 cu ft per min.



Since you can't overvent a steam main, I'd place a Gorton #2 on each main and see what that does. My system has Gorton for main vents and Ventrite adjustables for radiator vents. (Gortons are available from Pex Supply on the internet.)

Radiator vents are another subject and you CAN cause a lot of problems by overventing your radiators.  ("Vent your mains fast and your radiators slow")

Your piping looks generally okay. You mentioned that you have now insulated the piping which should be a big help to the system.

You might also want to take a look at Gerry Gill's website. He's the Cleveland steam pro who wrote the book on venting. He has a lot of good steam articles there including a very good one on venting. http://www.gwgillplumbingandheating.com/

- Rod

sean_b

venting

would it help to have an additional vent added to the rear main?  the mains have Ventrite vents, and what the heating system installer called thier largest - maybe 3/4" i *think* he may have said...  Do they make larger vents?



again, the main does vent, it's just the radiators that seem to take forever to heat up off that main.  but then i can hear them venting also!  quite a bit of venting actually!  so i am confused if i can hear them venting, and feel the air coming rushing out, doesnt that mean that steam is making its way to them pushing out the air?

nicholas bonham-carter

smith header

why not get out the installation manual for your boiler, and compare the mfg's required piping with what was installed. i would think that the header should be one diameter larger than the riser, and maybe they would have specified 2 risers instead of only one.

while firing up from cold, can you feel any difference in the initial heat up of the 2 mains about 10 feet from the header. if the header is undersized, then that with bad main venting would cause the speed of steam arrival to be much slower.

was the new boiler properly sized to the radiation? if you were slightly under sized, that would exaggerate any restrictive difference between the 2 mains, especially with weak main venting.--nbc

sean_b

re: Main Vents

Thank you Rod!!!!  I just went to the basement and verified they are VentRite #35's - so the smallest of the small!!!  Not good.  I am going to call some local plumbing supply places to see if they sell those Gortons.  Will the Gortons fit on top of the same stem or nipple or whatever it is that the ventrites are on?



Thanks!!!

Dave in QCA

Main Vents Etc.

Rod and Tom have nailed it!!

Also, just check the I&M manual, and your boiler calls for a 2" riser and header.  It looks like that is what you have.  Your building piping is connected to the header perfectly.  Your general contractor does not know beans about steam piping, and should not be offering erroneous advice.



The capacity of a main vent does not have much to do with the pipe size, but rather the size of the passages inside the vent.  The main vents that your contractor installed vent at less than half the rate that the old standby, the Hoffman 75.  They vent at about 1/10th the rate of a good Gorton #2.



What you want to have in your steam system, is a venting set up where the mains vent very fast and the radiators slow.  What this will do, is allow the steam to work its way quickly down the main to the path of least resistance, the main vent.  When the steam gets there, the main vent closes, and then the steam begins to flow into the radiators, evenly, at the same time.  When your main vent is inadequate, like the ones you have, the steam will begin to flow into the radiators way before the steam gets to the main vent.  As the steam flows into the nearest radiators, given the huge mass of the cool cast iron, those radiators will actually tend to draw in steam to take the place of the steam that is condensing to water, and so the progress of the steam moving down the main will slow down, and perhaps actually stop until those near radiators that are hogging the steam become fully heated. 



A gorton #2 on each of your 2 mains would be good.  I would the close all of your radiator vents to position 5 and see where that gets you.  You can fine tune at that point, but nothing is going to work right until you get some decent main vents installed.

sean_b

re: smith header

I do have the manual.  It calls for what is there - a 2" header and 2" riser and also for a 3-5 section boiler (mine is 3 section) they want 1 riser. 



the diagram doesnt show the piping past the header though - basically shows it going from th header to a single pipe going up to a main - doesnt show how to do it if there are 2 mains - i guess they dont consider that part of the "near boiler piping"

Rod

Steam to the Radiators.

I think what is happening now is that your radiator vents are doing most of the venting for the mains. This is why you hear all the hissing. Steam enters the mains as quickly as the air leaves the mains, however on reaching and entering the first radiator, things change. The steam in this radiator (and others the steam reaches first) condenses, going from a volume of 1 cu ft. of steam = 1 cu. inch of water. This creates a huge vacuum which more steam then rushes in to fill. This huge need for steam can slow down the steam traveling in other parts of the system.  The idea of using large main vents is that air is quickly removed from the mains so that steam reaches all the radiators at approximately the same time. The condensing in the radiators can then be controlled by (the vent) the speed at which the air is leaving the radiators.  This what is meant by "Vent the mains fast and the radiator slowly".

You said you tried turning the radiator venting down but had problems with it . That's because these vents are now doing the job of the main vents. With proper main venting these vents will be just be able to look after their individual radiator and you should be able to turn them way down with no problem.

- Rod

sean_b

Update - new main vents - and Should air be sucking into a radiator vent?

Ok, so I just went the the plumbing supply store and put on two brand main vents.  My mains now have Gorton #1's on them.  there was one store nearby that had them in stock and no one had #2's so i figured i'd try the #1's - they vent triple the rate the ventrite #35's do so it HAS to be a big improvement.



I am running the system right now.   All radiator vents have been set to 5.  Pretty much all of them have heated up and done so fairly quickly!  The mains vented much more quickly but again that rear main was slower to close still by a few minutes.  Both both are very hot all the way to the main vents etc...



Next issue is the one radiator that is furthest away on the second floor and on the rear main still took forever to heat.  I put my ear close to the vent on it and could hear it sounded a little like air being sucked in and out of it.  So i placed a piece of teflon tape very loosely over the top and sure enough it would  puff up when air was venting out and suck into the little hole a bit when air was being sucked in.  Now each time it sucked into the hole, i started hearing some gurgling sound down in the pipes some where - not a heavy gurgle but kind of a mix beween boiling water sound and maybe the sound of very shallow water gurgle if that makes any sense.  So air comes out of this vent, no gurgling sound, then when air sucks in and the teflon tape seals it up so it cant gt in, the gurgling sound really gets noticeable.  BUT when i stopped the air from being sucked into the radiator with the tape, it heated up very fast!  So strange.  Should there be some sort of vent that only lets air go one way?  I dont know how if there is water in the line, i could get it out...

Dave in QCA

Hmmm...

Excellent work!  How long did it take for the steam to make it from the boiler to the main vent?  It should be 3 minutes or less, if you start counting when the steams starts to leave the boiler.  If it is taking longer than that, you still need to increase the venting, especially on the line that is taking longer.



Regarding the other issues with the one problem radiator, I'm not sure what's going on, but I suspect that it would have heated up at the same time it did, that preventing it from sucking air back in was coincedental to the arrival of the steam.  If it were me, I would go around the house, and reset every vent to position 4, except the vent on this radiator, and I would set it at 7 or so, and see where you get.

sean_b

re: hmmm

I am pretty sure it is less than 3 min for each.  Now the pipe and vent itself warmed up very significantly in less than 3 min for sure, but as for actually closing i am not sure.  how do i know for sure if they have closed or not?  i held teflon tape in front of them also to try and check, but by the time I did it seems they must have been closed because no air was coming out.



I will go around and retest with all vents at 4 except this one and try it.  I have to wait a little bit for the house and system to cool - that last test brought me up to 71 deg in here!!!  i'd like to try and time it from cold start....



 

Dave in QCA

When does a Gorton close?

We have had a few exchanges on this subject.  The Gorton tends to close around 130-140 F.  It does not make any sounds when this happens, so it is a little hard to tell.  What I usually do is feel the pipe that the vent is connected to.  There is little doubt when the steam arrives, it is suddenly VERY HOT!!!



Let us know your progress.

sean_b

another update - main vent spitting a bit

So the latest update - I ran the system again from almost cold - luke warm anyway and there is still some issues with the main venting i think.  i turned all rad vents to 4 with the exception of the problem radiator, which was set to 7.



The front main (is the one that vents and heats the fastest) vents very fast and hard with(both have new Gorton #1's)  - doesnt seem quite right - i mean there is a lot of wind that comes out of that vent and after a couple minutes when the steam must have started coming out at its fastest, it even started to spit out some water - it was blowing the teflon tape i was holding in front of it all over the place - very strong air pressure being forced out.



On the other hand, the rear main does vent, but with nowhere near the same pressure coming out of the vent as the front main has.  so i cant imagine that it is undrvented.  it just isnt getting the pressure it seems.  it did take more than 3 min for sure for the stem that the vent was on to get pretty hot.  More like 8-10.  Oddly however, the problem radiator (which is on the rear main) did heat up at the same time as the others about 15 min to get good heat to them. 



So seems if i lower most rads to 4-5 range, keep the problem one open more, it might be a bit better balanced.  however, i am not sure what to make of the main venting issues. 



How might someone best diagnose a venting issue in a main?

dannyboy

pipe it

most residential boilers today require a 2-1/2" header

sean_b

update - something wrong with rear main still

Ok, so my update is that I have tested out the timing of how fast those two mains heat  up a couple times now. 



The front main with the Gorton vent it heats up even quicker.  From the time the boiler starts sending steam, i'd say about 4 min or give or take for the vent to be pretty hot.  By the way, this vent vents pretty fast and furiously can really hear the air rushing out fast.  Also, the vent was directly under a beam so ti was on a 3" nipple i'd say.  The old Vent-Rite vent used to spit a little cruddy water out, but this Gorton spit a great deal more out.  Is this normal to have happen?  The vents are located at the end or the returns (about 18" back from where they drop off to the floor).   I added a couple elbows, and a 4.5" nipple to go around the beam, and now the vent sits high and dry about 9" or more above the top of the main return.  No more spitting. 



The rear main however, something is still wrong.  I think that main is still trying to vent through the radiators maybe - air comes through the Gorton vent, but very slowly.   It takes a good 20-25 minutes for the vent itself to get hot.   But most of the main itself is hot but so are all the radiator riser pipes (or take-offs?).  My understanding is that if it were venting properly, that vent would be hot in no time, and the radiator risers still cool pretty much until the main vent closes.  There is not any water hammer in this pipe though - any ideas what else might be causeing the vent problems?  Can there be water blocking it and no water hammer?  I am at a loss where to even start!



Also, my water is (and has been for a while) quite dirty.  The heating guys are supposed to come back to give it another (2nd) skim soon, but I think it may be surging as the top of the sight glass seems damp and moist, not water cascading down or anything, but definitely moist.  Also the water moves up and down quite a bit.  Not violently, but when when the boil really starts going it seems to slowly go up and down a couple inches, or more at times.  Also, when at rest, the water level comes back up to w/in normal range.  But after it has been running 20 min it does a low water self-diagnostic test - shuts the boiler and checks the water level after 60 sec.  supposed giving time for foam to settle I think - The water however sometimes makes it almost all the way to the very bottom of the sight glass.  Sometimes the LED indicates low water and boiler doesnt come back on right away.  Also, each time this has happened the water feeder has NOT come on (which is good I think because after it sits a few more minutes the water does make its back up to the normal level (between min and normal).  Do you think I am producting wet steam which might be messing up the rear main?  Why isnt it messing up the front main?



Thanks again for taking time to read this!  You guys have been incredibly helpful so far, hopefully I can return the favor one day!



by the way, i just now purchased Dans book "We got steam heat!"!!!  Cant wait to get it! 

Dave in QCA

pictures

Can you take some pictures of your mains, how they run, and especially of both vents.  Another thing you might want to check is that there is no sag in that back main.

sean_b

re: pictures

i will try and take some when i get home this evening and put them up.



There was sag in that rear main at one point (induced by a contractor we had do some remodeling work for us), and a couple weeks ago the boiler install folks had come back and discovered it and corrected the pitch (seemingly).  Prior to fixing the pitch - the main would get hot up to a point, then be cold beyond that point.  There would be some hammer noise and after a long time of the boiler running steam would eventually make its way past the sag (and pooled water). 



Since fixing the sag, there is no longer any point along the main where the heat stops dead like that.    It takes a long time to heat up still, and after say 15 minutes of steam being produced, the main pipe is definitely hotter up to the point of the last radiator take-off than it is at the main vent (which is pretty much at the end of the road). 

BobC

how fast

I think Dave is onto something with making sure there is no sag in the back steam main.



Next time you start from just a warm boiler see how the steam progresses down that rear main. If it slows down at a specific section there may be water pooling in that area of the pipe - pooled water will collapse steam.



Check that main and any radiator leaders that come off it with a level to make sure all the piping is sloped correctly. All building sag with age just like we do.



Until that boiler water is clean and the water level stays within about +/- 1/4" it's going to be difficult to balance the venting out. Even still it might be worth throttling back the rapidly heating radiators down to 3 or even 2. The Ventrites will vent between 0.036 and 0.125cfm from a setting of 2 through 8. the vent is off if it is set to 1.



Bob

sean_b

sag

Thanks Dave and Bob!



Bob maybe you were writing your response before you saw my update, we posted just a couple minutes apart.  I was replying to Dave re: the sag in the pipe...



"There was sag in that rear main at one point (induced by a contractor we

had do some remodeling work for us), and a couple weeks ago the boiler

install folks had come back and discovered it and corrected the pitch

(seemingly).  Prior to fixing the pitch - the main would get hot up to a

point, then be cold beyond that point.  There would be some hammer

noise and after a long time of the boiler running steam would eventually

make its way past the sag (and pooled water). 







Since fixing the sag, there is no longer any point along the main where

the heat stops dead like that.    It takes a long time to heat up still,

and after say 15 minutes of steam being produced, the main pipe is

definitely hotter up to the point of the last radiator take-off than it

is at the main vent (which is pretty much at the end of the road). "

BobC

Clogged return

Sean,



You mentioned the LWCO was shutting the system down but that water was finding it's way back to the boiler after a few minutes and that the water feeder was not feeding water (probably because of a built in delay). Your return pipes maybe partially clogged with crud and might need to be snaked out. You might want to adress that before having the boiler skimmed again.



Post some pictures of that rear main, it's vent, and the return. Also how long is the return back to the boiler?



Dirty boiler water contributes to wet steam, maybe it is effecting the rear main more because of it's length?



Bob

Dave in QCA

Test that Gorton #1

I am going to recommed that you remove the back Gorton that you just installed to see if it is clear.  I bought 4 Gorton #2 vents last summer.  One was stuck closed, the others were fine.  I was in the process of getting approval to send it back, and I was going to pack it up.  Even though I could not blow air through it before when it was positioned in the upright position, and also, it had no internal clatter from shaking it, like the others did, I should it real hard again.  All of a sudden, it began to rattle.  I turned it upright, blew through it, and it was fine. 

I suggest you try the same thing.  You might also try running the boiler with the vent removed and see how fast the steam gets to the open pipe.  But, watch it VERY closely, and be prepared to kill the boiler FAST when the steam arrives!  That should give you some comparison of how it works both with and without that new main vent.

Dave in QCA

Return piping pictures please

I was just looking the original pictures you posted of your boiler.  It is hard to see what is going on with the return piping behind the boiler.  Please take some more pictures, I am seeing something that does not make sense.

sean_b

re: clogged return

Thanks Bob! 



i will definitely get more pics up this evening.  Couple questions on your comment.

Could a partially clogged return pipe cause slow venting in a main? (by the way both returns join up into a single return pipe just before entering the hartford loop(?) and then going back into the boiler... so i would think a clogged return would slow both, unless of course the clog is only in the rear return and located before joining the front main return pipe (see attached diag.)



second question is where do you start/stop measuring the return from?  the last radiator take-off to where they re-join? 



As for the length of one return vs the other, both loops (front main/return and rear) are pretty close in length and almost mirror images (front slightly longer in total).  In the absence of pics, i just drew a diagram of how the basement system is piped and attached it.  I dont have dimensions (because i am in my office at work!) but it can give you an idea....

sean_b

return piping

Thanks Dave, I will gets pics asap.  I put a little diag in my last post to illustrate - it might help.



  Also, re: the new Gorton vent - after it spit water last night i took it off and made sure i can blow thru it - no problem.  when you shake it you can definitely hear everything moving freely around also.... 

Dave in QCA

Return questions

Sean,

Good job on testing the vent. 



I see where your return drop down, go around the chimney, and then come up to the boiler, and turn up and connect into the hartford connection.  That is all good.



I also see where the equalizer goes down, around behind the boiler, and connects into the return tapping of the boiler.  Just behind that return tapping is a tee.  The side inlet is coming from returns/equalizer.  The connection going back, comes through a ball valve that is open, and before that, it is coming through a cast iron strainer.  Before that, I can't see.  Where is that line coming from?  What is it connected to?  Why is there a strainer in it?

sean_b

i think i am with you...

Thanks Dave,



i am not sure what the strainer is!  is that the black thing that connects to a green piece which is then connected to a red piece?  VERY TECHNICAL! haha!!! 



the bottom left corner of the middle picture i originally posted?  If so that connects to a new megastore water tank that i also had installed.  i will post pics of that also tonight.

sean_b

More Pics!

Wait, I just found i have some more pictures that I did not originally post because my original question was about my header/riser piping!



You can see both returns coming down and rejoining, and how the megastore is piped etc,..  can kind of see where the vents are in last photo behind the megastore but i will put better shots of that later

BobC

Should not normally cause venting issues

A clogged return won't slow venting unless the water backs up enough to block that vent. It's just that if we fix enough problems the cause of a particular problem often becomes clearer.



You seem to have a  parallel flow system so your dry return would run from the end of the main after the last takeoff to the point after the vents where it heads for the boiler return; the wet return is anything below the boiler water line. When they installed the boiler, did they check the existing wet returns to be sure they were clear?



As long as the mains are about the same length the venting on each should be about the same. I think Dave mentioned removing the rear main vent and see how it vents then - just be sure to be ready to kill the boiler when the steam reaches the open vent pipe.



How many sq ft of EDR do you have being fed by that 3 section boiler?



Bob

Dave in QCA

indirect water heater

OK, I get it now.  You are connected to an indirect water heater too.  The line is drawing the water from the bottom of the boiler, through the strainer first to protect the pump from sediment crud.  

I thought it was somehow connected to your houe return piping, but it is not.

sean_b

Updated with Pics

Bob and Dave, I took more pictures and numbered them to put them in

some sort of order.  The first 2 show my vents and how/where they

are connected and the ends of the returns.  They are about 18" or so back from where the return

drops to the floor.  The vent on the left is for the front main.  It was

spitting a bit of water before as it was only on that first nipple

directly under the beam about 3 or 4" off the main (I had read somewhere

else it should be closer to 6") so i raised it using those elbows and

another nipple.  The vent on the right is for the rear main.  What you

see is the heating installers attempt to get it to vent better.  He

thought there was a vacuum happening as air would suck back into and out

of the ventrite that was on there so he added a vacuum breaker to it

(says Hoffman #62 vacuum breaker) on it. 



The next 2 pics show just the boiler and some near boiler piping. Photos

6-9 show the rear main piping starting at the boiler and looking leftish

and moving clockwise to the center of the basement where the returns

come back.  In 10-11 you can see in the return pipes that after the very last

radiator takeoffs, the mains hit reducers going from 2" down to 1.25"

pipes then both returns duck under a beam.  Photos 12-16 show the

front main and then some return piping

again.



Timing: I ran the

system again from a Luke warm starting point ( had been off for at least

45 min) to time things.  I have a hard time knowing for certain the

starting point of steam production so from the time the burner started

(prior to steam production) it took about 6-8 min before that front main

vent go too hot to even touch and the front rads were heating nicely

BUT the front  vent still vents so fast and furiously that it still

sucked water all the way up the new extended stem I made for it! Not

much but gave a nice squirt.  (btw the ventrite spat all the time also

but not a ton). 



Rear Main: Then, 8 min later

(t+16 at this time) the rear vent finally started to vent  pretty fast -

loud and fast enough I could hear it across the basement with boiler

firing.  It vented for a bit then slowed down.    The odd thing was it

was still cool to the touch.  Also during this entire time the main pipe

was seemingly heating up pretty evenly as far as I can tell - pipe was

hot at each radiator takeoff but not too far up each radiator pipe.  But

they didnt really heat up in series like one after another.  No cool

points on the main until you got past the last rad take off and to the

vent (i.e. the return pipe was only warm - not hot like the main between rads).  The main vent  still only pretty warm (no longer cool).  Then

the main vented fast again for a min or so, then slowed again... Still

only warm by t+18.  Then finally by t+20 it got too hot to touch. 



By t+25 to 30 or so, all radiators were producing a lot of heat - even the furthest away problem rad.



ALSO - i talked to installer this morning.  Two weeks ago when they fixed the sag in the rear main (hopefully fixed - maybe still an issue?) he said they suspected a clogged return also - took apart unions, inspected and was free flowing.  Also, they are coming to skim again this afternoon. 

Dave in QCA

Two issues.

This pictures of your 2 new vents are very helpful.  By the way, the vacuum relief vent was bogus on your installers part, he was barking up the wrong tree.  But, it will cause no harm to the system.



The photo of your vents shows me that you are not have just a little dribble of condensation coming out of the front vent.  I can tell from the rusty water streaks that it is squirting a lot of water, and it is rusty dirty boiler water.  That indicates that the boiler is still dirty, and needs to be skimmed much more to remove the oil and crud.  What is most likely happening, because of the oily water, it is causing water to be thrown up the boiler riser with the steam and it is enough that it all can't go back down the equalizer pipe.  So, it is heading up into your steam piping.  Naturally, it is going up the first pipe it comes to, more than the second.  So, you are getting a lot of water thrown up your front steam main.   This is going to cause all sorts of steam distribution problems and your system is not going to settle down until they do a bunch more skimming, which will get your boiler to be able to produce dry steam.



There is an additional thing that your pictures show, and it is of concern.  Your indirect water heater is being heated by water taken from the return connection and pumped by a small electric pump, through the exchanger on the indirect tank, and back to the boiler, where it is being discharged into the boiler through the skim port.  That skim port is at, or slightly above the normal water line, and coincedentally, directly beneath the supply port of the boiler where the steam exits.  This seems to me to be a recipe for producing wet steam.  If the pump is running to heat the water tank, it will be shooting water (at a temp lower than the boiling point) into the steaming area of the boiler, right beneath the point where the steam is trying to exit.



I have read the installation manual for your boiler, and I do not find any indication that this connection is approved for the purpose that your installer has used it.  I have also looked for additional connections that could be used, but do not find any.  If I were you, I would insist on communication from a Smith Boiler Representative in writing, or in person with you present, stating that the skimming port can be used as a return port for a pumped line used to heat an indirect water heater.  I strongly suspect that Smith Boiler will NOT approve it.



You will get this worked out.

Rod

Change the HW tank return

I agree with Dave. The skim port location is NOT a good place to return cool water. (In fact the only worse place i could think of would be to dump it straight into the header) It has got to be causing a hindrance to the production of dry steam. I would definitely have that changed.

Edit: Picture and comments removed as better solution suggested.

- Rod

Dave in QCA

Short Circuit

Rod, that's a good idea, but I'm affraid it would only short circuit because the water is being drawn from the return piping, just behind the boiler. 

I did discover that there is an unused return tapping at the front left corner of the boiler,  perhaps that would work.

sean_b

HW tank return

Dave and Rod, thank you!!  I just spoke with the Smith rep for my area, and he's checking into it - needs to check with the Mega-stor people also i guess. 



Rod, would leading it down to the return piping where you indicated stir up and cause more sediment and gunk etc to be sent into the boiler?  I also think that line goes around back of the boiler and connects to the input of the HW tank.



The HW tank is on it's own zone also, would that make a difference?  Or could there times when the boiler is already firing, producing steam for the house, then the HW tank calls for more heat, so it shoots cool water into the boiler while it is making steam?!?  This sounds like a recipe for disaster and could make the boiler crack or something.



by the way, im looking at the install manual again now and like Dave said, there is nothing showing the way to connect an indirect HW tank.  However, they do show hooking up  a tankless HW heater coil - it looks like a module that might have to slide into that panel where the skim port is?  I am not sure!   Maybe goes where the LWC stuff is.

Dave in QCA

Side Location for Steam Boiler

Sean, keep reading.  The instant hot water coil for the steam boiler is on the side, near the back.  I see in you photos that you have a filler plate there.

Rod

Missed that!

Dave- Thanks for pointing that out. I missed seeing that in the pictures and did the dumb old "assume" that the outlet was coming out of a separate boiler port. Might it be beneficial to use the new found port as the source port and the one now used as the source as the return port?

It might provide a few degree hotter water.

- Rod 

sean_b

re: short circuit

Dave, I was having some trouble with the LWC probe and the technician drained some water directly from the bottom of the boiler from that bottom front left port - so i think that goes directly into the bottom of it.  Could the HW tank return be fed back into here and still be able to drain the boiler if/when needed?





Also this leads to my next question - The manual shows the CW makup being connected directly to the boiler return line that is currently feeding the HW tank (the one with the electric pump).  However, the CW line is basically connected to the steam return piping that Rod indicated.  If makeup water can go in there w/o short circuiting why couldnt the HW tank return go into the port Rod indicated?  Could there be something, maybe the pump itself, in the boiler return line that currently feeds the HW tank which prevents the makeup water from getting past it?  i have seen the water feeder in action and it does kick on for about 30 seconds once every few weeks or so, and definitely raised up the sight glass water level significantly when i saw it working.

Dave in QCA

It will short circuit

If your water heater pump is running at the same time that the boiler fill opens and runs water into the piping, it certainly will be drawn in by the pump.  When the makeup water shuts off, the heater will again start to receive hot boiler water.