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Dead men rolling in grave

I'm thinking of making some changes to my steam heat system, so I thought I would put this on the wall for some recommendations from the experts.  I've been in my house for 22 years.  When I bought the house, it was a two pipe steam Trane Vapor System with the original coal boiler which had been converted with a gas burner.  It was piped just like shown in all the diagrams with direct return trap and check valves.  In 1996, I had the boiler replaced with a weil mclain.  The near boiler piping was changed and the direct return trap scrapped ( I was told I didn't need it anymore).  I was told I would save money with the new boiler, but the bills probably went up slightly.  I've had heat in all the rooms over the years and never gave the system much thought until recently when I discovered this website and began to analyze how it was working.

The boiler fires and begins to make steam quietly.  Air is purged through the end of steam main vent and the condensate return vent.  Gauge pressure is about 8 ounces.  After 10 minutes, steam has circulated through the steam main loop in the basement and reaches the end of main vent, which closes.  Over the next minute the steam progresses to the boiler, then refluxes up the condensate return until it hits the condensate return vent, which closes (11 minutes).  Steam continues backward horizontally in the dry return line at least 10-12 feet where the pipe disappears into the wall and I can't feel it anymore.  Air can no longer escape from the system.  The boiler continues to fire for another 8-9 minutes for a total cycle of 20 minutes.  With the vents closed the pressure rises to 2.5 to 3 psi.  The boiler shuts off because the thermostat is satisfied.  Pressuretrol appears to be set for cut-out at 8 psi and cut-in at 6 psi.  With the outside temperature 25-30 degrees, the boil does not fire again for one hour and 50 minutes.  Most radiators only fill half way with steam. When the boiler shuts off, the gauge slowly shifts to a vacuum of 5-6 inches as steam condenses. 

My initial plan was to replace the original steam traps which I presume have failed open.  I was also considering a vaporstat.  The way the system is set up, steam never reaches the traps and a vaporstat will probably just cause short cycling.

I've posted pictures of the return piping and can think of four possible solutions.  1). Put a check valve between the steam return and condensate return.  2). Lower the condensate return below the water line with +/- check valve.  3). Number 2 with an additional check valve and direct return trap like in the original design. 4).  Leave it alone. It works

Pictures to follow


  • SteamTraneSteamTrane Member Posts: 11

    Here are the photos
  • crash2009crash2009 Member Posts: 1,484
    I am rolling in my grave

     and I'm not even dead yet.  This boiler is piped completely WRONG.  No header, no equalizer, no hartford loop, returns joined above the waterline.......

    Take it apart and start over.  Get Pat Girioux over for a look.  He can straighten it out and make it work great again.   
  • RodRod Posts: 2,067
    2 pipe steam

    Hi-. These systems run on ounces of pressure so having the pressure so high is destroying (or has destroyed) your vents and traps besides the fact that building that much pressure costs more fuel. The Empire State Building runs at a maximum of 3 PSI so 6 to 8 PSI in a home is a it ridiculous.  The reason the steam pressure is so high is probably because this is the only way you can get to the system to work in its present the excess pressure forces the steam into the radiators despite the failed traps and failed vents..

    The areas I see that need attention are:

    1. The near boiler piping - There is NO header or equalizer pipe, nor a hartford loop from the wet return to the equalizer pipe.. Take a look at the installation piping instructions for that boiler or if that isn't available, of a later model boiler of the same capacity.

    2. As noted in the attached photo the pipes returning from the steam main and the return main should not connect until they are well below the boiler's waterline. This stops "short circuiting" (cross feeding)  of stem pressure from the steam main to the return main. You want the steam's path  routed from the steam main through the radiators and then as condensate back through the return main.  Check valves really aren't of much help.

    3. A vaporstat works the same as a pressuretrol but is much more accurate at low pressure. Pressuretrols tend to go "weird" at lower pressures. Since the system was originally designs to perate at very low pressures I would install a presuretrol to achieve this.

    4. Radiator traps -These can be rebuilt as there are replacement capsules for the inner workings.  This should be done in the summer when the heating system is off as the traps need to be all repaired at the same time. If you only repair a few and there are others that are open this allows the steam to get to the new "good" traps through the return and destroy them. An alternate to traps is to consider orifices. If you went with orifices you would still have to open and  remove the inner works of the old traps so the condensate could pass freely through.

    As whether to leave the system well alone that is up to you. Building the extra pressure just so a crippled system will work has got to be costing you money fuel wise.

    If you have more questions let us know and we'll do our best to answer them. You might also post more pictures or a diagram of your system as that would be helpful.

    - Rod.
  • SteamheadSteamhead Member Posts: 11,373
    Fix the piping around the boiler first

    then see how well it works!

    For some views of proper near-boiler piping, go here:

    and click on the various Drop Header links.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • SteamTraneSteamTrane Member Posts: 11

    I want to put a few things in perspective regarding my post.  I've spent the past two months reading posts on this site and everything else on the internet I could find regarding steam.  I've read Dan's book.  I now know the theory of how these systems were designed to work.  I realize how ugly this piping looks compared to the pictures.  I know the system should run at low pressure and how the radiator traps should function.  But at this point, I am just a homeowner and the system in its present state heats my house, and after talking to my neighbors, does so probably at a comparable cost.  It has done so for the past 16 years. 

    Currently I have three kids in college and repiping everything is probably not cost effective.  Changing radiator traps seems to be useless since the radiators can't fill completely and steam never reaches them.  A vaporstat might help a little.  It would probably cause shorter burn cycles with some condensation in between which could nudge steam further into the radiators with each burn.  My thought was that re-piping the area circled by steamhead might be a first step.  I was curious how people would do this and whether there might be any unintended consequences such as water disappearing from the boiler, pressure in the boiler preventing condensate returning, etc.  Also, although the header looks awful, the boiler seems to make and deliver steam quickly and quietly.  Would changing the return piping unmask the header errors and cause problems such as water hammer.
  • SteamTraneSteamTrane Member Posts: 11
    More photos

    Sorry Rod.  You circled the area on the photo.  Anyway here are two more photos of the supply side piping for those interested.  I believe that if I can keep the steam on the supply side, the main return vent will continue to vent allowing steam to completely fill the radiators as intended (at low pressure). 
  • SteamheadSteamhead Member Posts: 11,373
    The place to start

    is the return lines coming down to the boiler. If you can only do so much at a time, start there. Dropping them below the waterline before tying them together will keep the steam from going into the return line and closing that vent. The system will heat much better.

    But the steam piping coming out of the boiler is like a yoke that can actually pry the boiler apart. There are no swing joints to allow for expansion. This type of boiler has gaskets between the sections, rather than push nipples, and they can leak if stressed. So at some point you will need a proper header installed.

    Yes, it's going to cost something to fix all this, but it won't be as much as a new boiler.
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • Jamie HallJamie Hall Member Posts: 6,693
    Rumble rumble...

    Your very first step, which won't cost all that much (and I do appreciate how you feel; you should try running a museum building these days), is to fix that little bit of piping where the return hooks into the main above the water line.  You don't have to -- right now -- fix anything else.  But fixing that one little bit will allow the steam to go out the steam main and through the radiators, and the condensate to come back through the return to the boiler, as it should.  The radiators will start getting hot as soon as the vent on the steam main closes.

    Now.  What you may find after you do that is that you have failed traps on the radiators.  In fact, I wouldn't be a bit surprised.  You will know this because the return will get hot starting at the radiators and working back to the boiler.  What you do is set the pressure as low as you can with the pressuretrol; say half a pound cut in and a differential of 1 (it may go lower, but I doubt it).  If the radiators don't heat at that pressure, raise the cut in sllightly, but go easy.  Then we hope that the valves on the radiators work.  Go around the system, and find the radiator which gets hot to the outlet first.  Close its valve about half way.  Keep doing this until you are down to the last radiator (don't forget to check the ones you have already done -- they may need to be closed further; always close half way from where the valve is -- that is, if the valve is already half closed, close it to one quarter and so on).  Now check the room temperatures; if their is a room too hot, close it's radiator a little more.

    This is going to take some time -- but it doesn't cost anything except patience.

    Having done that, all your radiators should be getting similarly warm more or less at once (probably not exactly).  Now to readjust the pressure: when steam starts to spill through those bad traps, dial the pressure down so the boiler stops firing.  The objective here is fire the boiler just long enough to get steam in the radiators, but not in the returns.

    Give it a shot.  The only cost is going to be fixing that one bit of piping.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • RodRod Posts: 2,067
    Boiler Piping

    Hi- Thanks for posting the second set of pictures.  Looking over the piping, one has to wonder what on earth the person that piped the system had in mind. I'm still trying to get a mental picture of how the system is configured.

    A few questions- 

    1. How many steam mains does the system have?

    2. Does each steam main have return line so that condensate in the steam main can return to the boiler?

    3. Does each steam main have a Main vent (s)  located near the end of the main?

    4. Are these vent(s) working?

    5. Each steam main in the system needs to have a Return Main - Do all the steam mains in this system have a return main?

    6. Does each Return Main have a return line so that condensate can return to the boiler?

    7. Does each Return Main have a Main Vent (s) located near the end of the main?

    8. Are these vent (s) working?

    9. I notice that you have two pressure controllers (pressuretrols), What are these configured to do?

    Could you also post some more pictures of your boiler, same views but taken from farther back so as to show more piping. I'm trying to figure out where each pipe leads. I can blow them up if I need to see detail.  i don't need any marking as I can use your earlier photos for that.

    - Rod
  • Dave in QCADave in QCA Member Posts: 1,660
    I could have been done in copper!

    I think that is about the only thing that could have made it worse.

    This is one of the best examples that I have seen where an otherwise good pipe fitter really messed up because he did not have a basic understanding of steam and he did NOT follow the directions.

    He did use black iron.  He did get all of his lines plumb.  The installation looks professional and neat.  If it was for a water system that was under pressure and pumped, it would probably be fine.  That is where the problems come in, where water will go in a pressurized system is one thing, but it has nothing to do with the proper configuration of close boiler piping on a steam system.

    I would agree with the earlier post that if you got your return line connection moved to at least 2-3 inches below the normal water line, you would be miles ahead in terms of getting the system operating correctly.  There are all of the other issues that need to be dealt with too, but if limited funds are a factor, this is the big one.  The steam should not be directly connected to the returns, and that is what you got.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • GasperGasper Member Posts: 131
    Thanks Crash

    How is your system doing these days?  Could you post a pic of your vaporstat?  Thanks
  • crash2009crash2009 Member Posts: 1,484
    edited February 2012
    It's running great Pat

      Disabled the water feeder, only short cycled 4 times this winter.  Heats the house at a 1/2 oz.  The gas company is paying me to heat the place now.  I still haven't built the instrument header.  The vaporstat is mounted temporary.  There is a pigtail below the picture.
  • GasperGasper Member Posts: 131

    Even snubbers, and little baby shut-offs......good job!  Did the balance problem work out?
  • crash2009crash2009 Member Posts: 1,484
    What balance problem

    The dropheader you built, Gerrys suggestion to break the 150 foot main in two pieces, and Steamheads suggestion for lot's of G2's, seems to be a winning combination.  All I had to do was figure out how much air was in the mains, risers, and radiators and vent accordingly.
  • SteamTraneSteamTrane Member Posts: 11
    Thanks all

    Thank you all for your interest and comments.

    Mr. Hall.  I will probably take your (and others) advice to lower the condensate return to below the water line.  Do you think a check valve is necessary?  Also is the need for a direct return trap obsolete?  Is this because the water line on the modern boiler is much lower?

    Rod.  I'll post some more pictures to try to give you a better idea of how the system was re-piped.  Originally one steam main left the boiler and went across the house.  At that point it split into two mains going right and left around the perimeter of the basement and returned to the boiler.  Two steam returns.  Two condensate returns come together from opposite directions and join above the boiler before dropping down.  Now the steam goes out the old main and one of the returns meeting in the middle and then filling the last return, returning to the boiler.  I'll try to make a diagram.

    Dave.  I don't want to defend this piping, but there were several guys involved.  They seemed to be pretty heavy duty pipe fitters and were doing several boiler replacements in the area at the time including a large church.  Since their truck logos did not match the company I contracted with, I believe they were subcontracted to do the work.  I challenged them a little, but ultimately had to defer to their "expertise".  It was 1996, and the internet was a barren wasteland.  There were no websites, info, or photos to search yet.  The "art of steam heating" was probably at its most lost point.
  • SteamTraneSteamTrane Member Posts: 11
    More photos

    For those interested, I found an old photo of the original boiler and piping before it was replaced.  The photo was taken from about the same vantage point as my first photos in the thread.  It shows the classic Trane vapor piping from the back of the boiler. 

    Rod  Here's a photo to help you follow the piping.  It's hard to back up to take a good photo since the room is small with several obstructions.  I'm working on the diagram.
  • SteamTraneSteamTrane Member Posts: 11
    Piping Diagram

    Here's my rendition of the piping diagram.  In regards to the pressuretrol, I don't know why there are two.  They are set exactly the same.  Settings are mentioned above.
  • Jamie HallJamie Hall Member Posts: 6,693
    Response to direct question

    Yes, just repipe that junction to below the new water line.  No, a check valve is not necessary or even desirable.  And yes -- the problem probably came about because the new boiler was not set with the water line at the same elevation as the old one.  This happens time and time again... unfortunately.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • RodRod Posts: 2,067
    Boiler Piping Problems

    Hi-  Wow! The photo and the piping diagram really make things clearer and sure proves the adage that "a picture is worth a thousand words"!  Let me look it over and I'll get back to you later today. I see a simple interim fix and an additional one.

    - Rod 
  • nznz Member Posts: 89
    My Two Cents

    As a fellow GPer, I've had the opportunity to discover the wonders of steam heating. I've been reading this thread and had a few thoughts, even though I'm a homeowner - I like to tinker, and have learned quite a bit from this forum, the books, and some trial and error. I'm no expert, but here are my two cents from one homeowner to another.

    1. Remember Dan's Gospel - Pressure goes from high to low (I'm paraphrasing). This means that if you have steam in your return lines, there is no pressure differential. This means the steam won't want to move, so the air is stuck in your rads.

    2. Buy a infrared thermometer. Since you're a GPer, you can borrow my Fluke one as long as you return it :) I loaned mine to MotownSteamer about a month ago. Or you can buy one from home depot for like $30-40. This will help you gauge a) if you have steam in your return lines, and b) bad traps.

    3. If you're thrifty, you can replace traps cheaper than you think. You don't have to buy new trap bodies unless they're destroyed. I bought new caps & discs on ebay for anywhere from 55-80% off the cost of new. They work great, I've replaced 27 of the 29 traps in my house, and I have some spares now too. Once I replaced my traps, I have better heat distribution in the whole house, since steam in the return lines was keeping air from getting out of some radiators, and in some cases the traps were clogged up with crud. Previously, I would have to crank up the pressure to get the rads fully hot. Now they heat evenly in most areas of the house.

    4. The near boiler piping should be fixed obviously at some point, but mine is sort of jacked and I've fixed a bunch of other stuff (venting, traps, etc.) and still improved the performance of my system without fixing my massive bullhead tee.

    /me steps off the soapbox he shouldn't be on...


  • RodRod Posts: 2,067
    System Piping Modifications

    Hi- I've attached a PDF on a possible interim piping "fix" and also another PDF on vaporstats. With the drawings and pictures a pdf seemed the best way to go.

    Let me know if you have any questions.

    - Rod
  • Hap_HazzardHap_Hazzard Member Posts: 1,349
    edited February 2012

    I got one of those infrared thermometers a few months ago, and while it does give you an idea of when pipes are heating up, it's kind of like putting your hand on a pipe at a distance. The accuracy is affected by the color and texture of the object you're pointing it at and a lot of other factors, and the farther you are from the target, the bigger the area it reads and averages, and the closer you get the greater the parallax between the sensor and the pointing laser. In other words, they're not terribly accurate.

    A few weeks ago I posted a picture of a digital oven thermometer. I've been using a pair of these to compare the time it takes to heat different radiators and sections of pipe. You can stick the probes under pipe insulation or ductape them to the objects you want to measure, then set the alarms to go off at, say, 180°, pop open a beer and wait and see which one goes off first. By moving them around you can get a pretty good picture of how the steam is moving through the piping during a heating cycle. For example, you can tell if steam is reaching the return or not by how much it lags behind the main in heating.

    Over the weekend I was at one of those discount warehouse stores, and they had these grill thermometers that are basically the same kind of device except that the display is remote, and it was a couple bucks cheaper than the oven thermometers I've been using. I don't know how well they work, or if you can use two of them without getting their signals crossed, but I thought it looked pretty neat. If you want to keep an eye on the temperature of your main while you're watching football, so you know when to grab your infrared thermometer and head downstairs, it could be the hot setup.

    And we thought they made neat toys when we were kids, huh? :-)
    1983(?) Peerless G-561-W-S
    3" drop header, CG400-1090, VXT-24
  • nicholas bonham-carternicholas bonham-carter Member Posts: 6,540
    edited February 2012
    Brilliant work rod!!!!!!

    This new boiler should have resulted in a reduction of fuel costs if it had been correctly installed. Now you say that the fuel cost has been about the same as before the replacement, so the savings are still waiting for you when you correct these problems one at a time. I reckon my new boiler and piping corrections saved a third of fuel consumption when I corrected for degree days. If only I had known what I know now 38 years ago!

    Incidentally, I am thinking of submitting an invention of mine to the kickstart website. It will reclaim the rotational energy of all the deadmen "rolling in their graves", which must be considerable!--NBC
  • Dave in QCADave in QCA Member Posts: 1,660
    Great Idea!

    nicholas, would that be called a Perpetual Motion Machine?
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
  • vaporvacvaporvac Member Posts: 1,512
    Maybe NO traps

    Just though I'd give my two cents as a fellow Trane Vapor/Vac system owner.  My system was never designed to have radiator traps, but work on the inlet side via orifices.  I'm not sure if any of the Trane Vapor systems had radiator traps, so perhaps you could check at one radiator or post a couple of pictures of your rads.  There's a post today (Helpless "Two Pipe Steam, cold radiators), where someone dealt with this very issue and resolving it with some new orifices worked wonders.  I'm not saying that's your problem, (cause it appears like you have further piping issues), but it's a cheap place to start.

    Two-pipe Trane vaporvacuum system; 1466 edr
    Twinned, staged Slantfin TR50s piped into 4" header with Riello G400 burners; 240K lead, 200K lag Btus. Controlled by Taco Relay and Honeywell RTH6580WF
  • SteamTraneSteamTrane Member Posts: 11
    Rod. Nice plan


    I like your plan because it restores the flow of steam in the pipes the way it was originally designed. I have two concerns with removing pipe S. One is that it creates an equalizer which I thought was necessary. Two, is it creates a second outflow from the header along with pipe C. That decreases the resistance to flow out the header. Maybe this the reason the ugly, improper header has not caused any problems over the years. If nobody has any major objections, I may have pipe S removed. I do want to go with a vaporstat also.
  • SteamTraneSteamTrane Member Posts: 11
    All rads have traps

    All radiators have traps marked trane corp, lacrosse Wisconsin. None have been opened or serviced since 1925. I can post some pictures. I was reading about orifices and might consider them. They may need less maintenance compared to traps which might need to be replaced in 5 years. There is no sense in doing either until I address the piping issues which cause steam to reflux retrograde through the condensate return.
  • RodRod Posts: 2,067
    Removing Pipe "S"

    With regards to your concerns about removing Pipe “S”, I think the “second outflow” does far more harm than good  It’s counterflow and blocks the rapid removal of air through vent “B” and short circuits the steam flow (think pressure differential)  from the larger pipe “C”.    The “C” was designed to provide ample steam to the system so therefore a "second outflow" shouldn’t be necessary.

    As an equalizer - I think the key to your system working properly is to get the pressure down. Normally these systems operate on ounces of pressure. If the pressure is dramatically lowered that diminishes the need for an equalizer in this situation.

    I originally considered just disconnecting Pipe “S” from Vent “B” and  using the remaining  Pipe “S” & Pipe “E” as an equalizer.  Since there would still be the necessity of draining condensate from the end of the Steam Main “B”, you would need to run a drip line from Vent “B” to a new Wet Return which was then would be connected to the boiler.  While there possible design advantages to doing it this way, most of the wet return and drip line would have to be redone when if and when you redid the near boiler piping.  Just removing Pipe”S” saves you from losing the cost and labor of the  “temporary” drip line / wet return. which you would need to remove later.


    I don’t see any downside to removing Pipe”S” as it would be quite easy do and if you aren’t happy with the results, you could always reinstall it.

    The connection of the drip lines from Main “A” and the Return Main definitely need to be moved to well below the boiler’s water line.

    Here’s is a good article of Dan’s on steam pressure and why lower steam pressure works better.

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