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Trying to understand old two-pipe steam system

I'm restoring a 1908 house in Iowa, which has what I've been told is an original two-pipe steam heat system. I have no previous experience with steam heat. I had a local heating guy install a new propane boiler, which is connected in to the original pipe and radiator system (mostly beautifully ornate radiators). When we tested the boiler a month ago for the first time, while it was still hot outside, we turned up the thermostat over 80 degrees and let the system run for an hour. When we did that, most (but not all) of the radiators heated up. The system was adjusted by him to run at about 2psi. We didn't touch the valves or bleed systems on the radiators themselves - most of them are rusted solid in whatever position they are in, but there were no leaks, and nothing came out of the bleed valves as they were. Now that the weather is getting cooler, I have the thermostat set to a reasonable temperature in the mid-60s (about 20 degrees above the outside temp), and the boiler only turns on for short periods of a few minutes at a time. The main radiators in the center of the first floor heat up (closest to the boiler and the thermostat, of course), and then the boiler turns off before getting any of the other radiators even slightly warm. A number of questions have come up while I've been looking this system over and trying to understand it:

1: When it gets colder out, and the boiler has to run for longer (presumably), will the heat start to make it to the upstairs radiators without any further adjustments, or do I need to free up the valves on the central radiators so I can partly close them? If so, how do I do that if they are corroded?
2: The setup of the radiators doesn't match what I see online about steam systems in general, as they all have two pipes going into the bottom of the radiator (a valve at one end and a simple elbow at the other), and a bleed valve at the top - which doesn't seem to be a normal setup for steam. The pipes in the basement are sloped, which does make sense for a two-pipe system for the condensate return, but I am fairly confused about how everything works. I did find some references to similar two-pipe steam systems which said they were very rare. Perhaps that explains why I can't find much information on these...
3: Do I need to bleed this system to help steam get to the upstairs radiators? If so, how? The bleed valves (if that is what they are) seem to take a square key, and I would need the right tool for that.

I don't have photos to upload right now, but I will take some if they would help.
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Comments

  • KC_Jones
    KC_Jones Member Posts: 5,722
    If you legitimately have bleed valves that take a square key, those are for a hot water system. Steam does not require any bleeding.

    Pictures will help a lot. Post an overall of a typical radiator, and pictures of the boiler installation, not too close so we can see all the piping, several angels to allow a complete picture of what you have.

    If it is steam, and it's cycling like you say, that's classic over sizing of the boiler, but there could be other factors at play.

    Also if you actually do have 2 pipe steam, that needs to run at very low pressure, ounces, not pounds.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Jamie Hall
    Jamie Hall Member Posts: 23,161
    Picture pictures picture. We're going to need them!

    As a first pass, though, I'm going to be that first, if you actually have main vents on the system, they're not working. And second, this thing is going to want to run -- as @KC_Jones said -- at a few ounces of pressure, not even close to 2 pounds.

    Oh and one other thing -- are the steam pipes insulated in the basement?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • gchrisman
    gchrisman Member Posts: 66
    I'll definitely get some photos later for you! The bleed valves are a square key setup, and yes, I was reading that this meant hot water, not steam - which made me worry that the heating guy installed the wrong setup. He assured me this was intended for steam...There is insulation on the pipes in one room in the basement - the room with the main plumbing drains. Otherwise the pipes are all just exposed. I don't see any vents anywhere in the pipe system, but perhaps I just don't know what to look for. The system pressure was set with a max of 2psi (or so the heating guy told me), but when it is operating now the pressure needle barely moves, so perhaps it is in the range of ounces.
  • KC_Jones
    KC_Jones Member Posts: 5,722
    Pictures of the item that takes a square key would be good too, I'm quite curious at this point.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • gchrisman
    gchrisman Member Posts: 66
    Will do - I'll get photos uploaded tonight when I get home. Thanks for your help!
  • mattmia2
    mattmia2 Member Posts: 9,572
    This isn't the customer of the guy that installed a steam boiler on a hot water gravity system that posted a couple weeks ago?
    PC7060
  • KC_Jones
    KC_Jones Member Posts: 5,722
    mattmia2 said:

    This isn't the customer of the guy that installed a steam boiler on a hot water gravity system that posted a couple weeks ago?

    OMG

    Could it be?
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • KC_Jones
    KC_Jones Member Posts: 5,722
    @gchrisman Look at the pictures in the below link, is that your house by chance?

    https://forum.heatinghelp.com/discussion/185262/old-basic-gravity-hot-water-boiler#latest
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • gchrisman
    gchrisman Member Posts: 66
    No, that's not my house, but it sounds like we may have a similar situation. The heating guy did show me an old expansion tank in the ceiling of the basement above the boiler that he said 'wasn't needed anymore' but that he wasn't bothering to remove because it was big and heavy...he did not exactly impress us with his competence, and we regret paying him at this point. Did he make the same mistake as the guy in the post you linked to? I'll upload photos later and you can hopefully tell me. If so, I'll have to work out what my options are...
  • KC_Jones
    KC_Jones Member Posts: 5,722
    It certainly sounds like the same situation. To my knowledge no steam system ever had an expansion tank in the ceiling, that is for hot water only.

    On a side note, it's actually pretty pathetic a professional can't identify the difference between the 2 systems. It's really quite obvious.

    Pictures will tell the story.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    mattmia2
  • ChrisJ
    ChrisJ Member Posts: 15,583
    How is this even possible?

    Please, pictures, all the pictures you can get.
    We'll do our best to help you.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • mattmia2
    mattmia2 Member Posts: 9,572
    ChrisJ said:

    How is this even possible?

    Gravity hot water systems have very large piping. Someone that hasn't a clue can look at it and think it is steam piping rather than gravity hot water.
  • ChrisJ
    ChrisJ Member Posts: 15,583
    mattmia2 said:

    ChrisJ said:

    How is this even possible?

    Gravity hot water systems have very large piping. Someone that hasn't a clue can look at it and think it is steam piping rather than gravity hot water.
    Professional contractor charging for their services.

    Hasn't a clue really shouldn't be an option.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
    KC_Jones
  • Steamhead
    Steamhead Member Posts: 16,796
    ChrisJ said:

    How is this even possible?

    Because- here we go again- you can't fix stupid!
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    mattmia2
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,452
    I almost had this happen. I was supposed to install a residential boiler in a UMass building a couple of years ago. We were supposed to start on a Monday....I had not seen the job yet.

    Myself and my helper were working near by the previous Friday and finished up around noon time, so I said to him "lets swing by and take a look there not expecting us but maybe we can take a look and see what were up against"

    On the way over he mentioned he had walked by the new boiler sitting on the floor in the shop. I asked him HW or steam? He said hot water I think it had the Hydrostat control on it.

    So they let us in to take a look and the old boiler was steam. The one at the shop was HW. The estimator that sold the job went and looked at it and took pictures!!!!! of the gauge glass no less!!

    And he sent the salesman from the supply house over to look at the job!!! And they both thought it was hot water.

    It did have a hot water loop off the boiler, so i guess you could cut him a little slack
  • ChrisJ
    ChrisJ Member Posts: 15,583
    I almost had this happen. I was supposed to install a residential boiler in a UMass building a couple of years ago. We were supposed to start on a Monday....I had not seen the job yet. Myself and my helper were working near by the previous Friday and finished up around noon time, so I said to him "lets swing by and take a look there not expecting us but maybe we can take a look and see what were up against" On the way over he mentioned he had walked by the new boiler sitting on the floor in the shop. I asked him HW or steam? He said hot water I think it had the Hydrostat control on it. So they let us in to take a look and the old boiler was steam. The one at the shop was HW. The estimator that sold the job went and looked at it and took pictures!!!!! of the gauge glass no less!! And he sent the salesman from the supply house over to look at the job!!! And they both thought it was hot water. It did have a hot water loop off the boiler, so i guess you could cut him a little slack
    He took pictures of the gauge glass, no slack.

    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Jamie Hall
    Jamie Hall Member Posts: 23,161
    It was a University -- what do you want? Practical intelligence?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JUGHNE
  • gchrisman
    gchrisman Member Posts: 66
    Photos, as promised. You can see the old green expansion tank above the new boiler. I've also included some photos of representative radiators and some of the piping in the basement. How badly did our contractor screw this up? What can and should be done about it? I appreciate your ideas and feedback - I'd love to know how to deal with this because winter is coming and my wife and I were counting on having heat! Thanks in advance for your help.















  • Jamie Hall
    Jamie Hall Member Posts: 23,161
    All I can say is... all together now: "You can't..."

    It wasn't a steam system. It was gravity hot water. And it's not going to heat well, if at all.

    Your contractor needs to come back, take out the steam boiler, take out the condensate receiver (adding insult to injury). Figure out how to go back to hot water, which will have to be forced circulation. Figure out how to rebalance the system, since gravity hot water and forced circulation are very different, and...

    I give up. You have a real mess there, and it's going to cost somebody big dollars to fix. Hopefully not you.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    gchrismanmattmia2David Sutton_6pecmsg
  • KC_Jones
    KC_Jones Member Posts: 5,722
    If he won’t come back and fix it, or refund 100% of your money, I’d be contacting an attorney.

    Absolutely not steam, and if it was that boiler is piped so wrong (for steam) it would be a tear out anyway.

    This is amazing, it should take about 5 seconds looking at the boiler to know what type is system it is.

    Sad.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    gchrismanmattmia2
  • Steamhead
    Steamhead Member Posts: 16,796
    edited October 2021
    The Slant/Fin Galaxy boiler is sold in both steam and hot-water models. So it should be a simple matter to convert it.

    All I can say is... all together now: "You can't..."

    ... fix stupid!

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    gchrismanmattmia2David Sutton_6
  • gchrisman
    gchrisman Member Posts: 66
    edited October 2021
    Thanks for all this - my wife and I appreciate it! I just sent off an email offering our contractor those exact three options: fix it (now, and at his cost), full refund, or legal action. We'll see which path he chooses...
  • KC_Jones
    KC_Jones Member Posts: 5,722
    Please keep us posted on the outcome.  Let us know if you need any further assistance.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • David Sutton_6
    David Sutton_6 Member Posts: 1,079
    We’ll at least he still has the old expansion tank hanging from ceiling 🤷‍♂️
    PC7060
  • gchrisman
    gchrisman Member Posts: 66
    OK, the update is this - my contractor is throwing up his hands, saying that he just replaced one steam boiler with another steam boiler, and that he wouldn't know what else to do. The good news is, he did say that he is refunding our money. This seems better than having him try to fix it, since I don't trust his 'expertise' at all at this stage.

    I have tracked down a different heating contractor who says he worked on this house's heating system years ago, and I plan to have him do whatever work is needed when he has time in a couple of weeks. In the meantime, I want to work out what the best approach is to fix the system at this stage, so I can judge the plan the new contractor presents me with. So, as I understand it, the basic choice at this point is between taking the system back to hot water (converting the boiler, removing the condensate system, and installing a circulating pump) or trying to convert it the rest of the way to steam (involving proper traps, vents, and whatever else is necessary to effect the conversion). Are there any other considerations here? Noise is an issue with the pump option - are there any quiet circulating pumps out there (the loud pump on the current condensate system drives my wife crazy)?

    What would you do?
    mattmia2
  • JUGHNE
    JUGHNE Member Posts: 11,042
    You are very lucky, the contractor is giving you a refund and leaving the equipment?

    How water circulating pump are almost impossible to hear unless you are standing next to them.

    That feeder pump and it's control, the M&M 150, constitute a large chunk of money.
    If you get to keep them, I could consider them to be sellable.
    mattmia2gchrisman
  • KC_Jones
    KC_Jones Member Posts: 5,722
    gchrisman said:

    OK, the update is this - my contractor is throwing up his hands, saying that he just replaced one steam boiler with another steam boiler, and that he wouldn't know what else to do. The good news is, he did say that he is refunding our money. This seems better than having him try to fix it, since I don't trust his 'expertise' at all at this stage.

    I have tracked down a different heating contractor who says he worked on this house's heating system years ago, and I plan to have him do whatever work is needed when he has time in a couple of weeks. In the meantime, I want to work out what the best approach is to fix the system at this stage, so I can judge the plan the new contractor presents me with. So, as I understand it, the basic choice at this point is between taking the system back to hot water (converting the boiler, removing the condensate system, and installing a circulating pump) or trying to convert it the rest of the way to steam (involving proper traps, vents, and whatever else is necessary to effect the conversion). Are there any other considerations here? Noise is an issue with the pump option - are there any quiet circulating pumps out there (the loud pump on the current condensate system drives my wife crazy)?

    What would you do?

    Pumps on a hot water system should basically be silent, whatever is on that tank is not a good comparison.

    I wouldn't even think about a steam conversion, and I'm a steam fanatic.

    I am utterly shocked by the other contractor still insisting it's a steam system. I mean, he really should find a new career if he can't tell the difference.

    The only thing I can think of is he's never seen a gravity system and AssUMed it was steam due to a lack of pumps. There are other, better ways to tell. For me the sight glass is a dead giveaway for a steam boiler. It's sad no matter what.

    Glad he is refunding you.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    mattmia2gchrisman
  • mattmia2
    mattmia2 Member Posts: 9,572
    edited November 2021
    Connecting a hot water boiler to your system is the only path forward that will give you a good system. If you end up with that boiler it may be possible to put the parts on it that make it a hot water boiler and use it, you will have to do a heat loss on the house and find out how good of a match it is to your house. You will also need to check with the manufacturer if that boiler can be set up as hot water(most boilers of that type can be set up as either).

    Do you happen to have a picture of the old boiler?
    gchrisman
  • gchrisman
    gchrisman Member Posts: 66
    Here's the only photo I have of the old boiler:


    mattmia2
  • PC7060
    PC7060 Member Posts: 1,155
    edited November 2021
    Love the bottle of boiler fluid sitting on top of old unit! 

    Can T believe there have been two cases of involuntary hot water to steam conversions in one month!  It’s going to be a interesting heating season!
  • mattmia2
    mattmia2 Member Posts: 9,572
    edited November 2021
    yup, that's gravity hot water. unless that is an old 3 part circulator in the shadow in the back on the left(but hot water either way)
    gchrisman
  • WMno57
    WMno57 Member Posts: 1,249
    edited November 2021
    gchrisman said:

    The bleed valves (if that is what they are) seem to take a square key, and I would need the right tool for that.

    Try a small 12 point (NOT SIX POINT) socket. 7/32 fits my 1916 Kewanee Boiler radiators.
    Your expansion tank looks like my old Thrush tank. These are hard to find in the event it develops a pinhole leak, and you need a replacement ASAP. Very few supply houses stock them.
    You can get a new tank from WWW.QUALITYTANKSINC.COM.
    They are inexpensive, and last about 7 times longer than a modern bladder tank. Also, our old large volume systems would need multiple bladder tanks since the average bladder tank is sized for small volume systems.
    Your radiators are beautiful! The wood trim shown in your pictures is pretty cool too. Please keep us posted on your project. I don't think you will be bothered by noise from a circulator pump.
    You can't fix stupid, but you can DIY.
    I DIY.
    gchrisman
  • PC7060
    PC7060 Member Posts: 1,155
    edited November 2021
  • ChrisJ
    ChrisJ Member Posts: 15,583
    PC7060 said:

    Love the bottle of boiler fluid sitting on top of old unit! 


    Can T believe there have been two cases of involuntary hot water to steam conversions in one month!  It’s going to be a interesting heating season!

    If they were piped correctly and actually worked there's a few on this forum I'd suspect doing it intentionally.

    But these two cases weren't done by them, the systems are broken and flat out wrong.

    Sad.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jumper
    jumper Member Posts: 2,226
    In defense of those contractors only old guys have seen steam or gravity HHW. I've never personally seen a HHW system converted to steam but there are stories. Presumably the radiators are over sized for steam so....
  • ChrisJ
    ChrisJ Member Posts: 15,583
    edited November 2021
    jumper said:
    In defense of those contractors only old guys have seen steam or gravity HHW. I've never personally seen a HHW system converted to steam but there are stories. Presumably the radiators are over sized for steam so....
    When I can't do a job I admit it and turn down the work.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • jumper
    jumper Member Posts: 2,226
    edited November 2021
    ChrisJ said:


    jumper said:

    In defense of those contractors only old guys have seen steam or gravity HHW. I've never personally seen a HHW system converted to steam but there are stories. Presumably the radiators are over sized for steam so....

    When I can't do a job I admit it and turn down the work.


    Chris knows enough to know what he does not know. Often meet folks who don't.
    PC7060
  • gchrisman
    gchrisman Member Posts: 66
    Thanks for all your help and advice on this! Here is where the situation is right now: the new heating contractor tried to talk with the Slant Fin people about converting the steam boiler to hot water. They said that while it is technically possible, it couldn't be certified or rated, and that therefore they don't want it to be done. In fact, they won't sell him the parts to do it, so we're at a standstill on that option. In the long run, it seems we will need a new boiler designed for hot water (plus the circulating pump, etc).

    Unfortunately, this isn't going to happen immediately (previously scheduled work, back orders, etc.), and I have a cold season to get through between now and then - can you give me any ideas about how to get the most out of this (totally incorrectly set up) system in the meantime? Basically, right now only four or five radiators in the house are heating up (the ones that are piped closest to the boiler, I think - but two are upstairs, so I'm not entirely clear on why these ones work). I've tried opening the manual bleed valves on the cold ones to get steam to rise there, but no luck at all so far. In a couple of cases, the pipes are hot right up to the main valves at the bottom of the radiator, but the radiator itself is still dead cold. The main valves are mostly stuck with corrosion, but as far as I can tell they are stuck open - the one I removed and replaced was in that state, and replacing it with a new one that I can open and close hasn't helped at all. Any ideas? If I could even get the radiator in the bedroom to heat up, it would be a big improvement. Thanks for your ideas!
  • pecmsg
    pecmsg Member Posts: 4,775
    The house Im in had a similar gravity hot water system. When the thatcher boiler used the last few gals of oil, I converted to NG hydronics. Like your pictures many large low hanging pipes in the basement ceiling. I was able to remove all the mains and replaced them with 1 1/4" and 1" mains. Separated the 1st from the second floors into zones and have not looked back.

    I'm surprised slant fin said that. That is a Hot water / steam boiler.

    Find a different contractor.
    1 maybe 2 days getting it running.
    1 extra day finishing.

    It will cost extra but get an accurate heat load loss performed. If that boiler is oversized and I believe it, is you'll need a new boiler. Donate that one to a habitat for humanity project and take the write off.
    mattmia2
  • mattmia2
    mattmia2 Member Posts: 9,572
    The parts to make it hot water aren't special slant fin parts, anyone that knows what they are doing can buy the parts from a supplyhouse.
    delcrossv