Click here to Find a Contractor in your area.
In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Need to contact us? Visit

Steam Heat - Losing a lot of water and 2 rads getting no/little heat

IanFIanF Member Posts: 5
An admirer of this site, I’ve owned a house with a one pipe steam heat system for just under a year.
Reading Dan’s Lost Art book and the advice on this site has helped improve my heating tremendously - including from installation of 2 Gorton #2 Main vents, replacing radiator vents, and insulation.

I’ve 2 major outstanding problems I cannot seem to solve (and 4 heating and plumbing companies later...) so I wanted to reach out for your help.

Does anyone know a good steam pro. in the South Orange New Jersey area (NJ 07079). I'm about 20 miles west of New York City?

Problem #1: Losing water...
I’ve found and had repaired 3 leaks in the steam pipes over the past year but I am still losing a lot of water.
My Weil McLain EG/PEG Series 5, Model 35 gas fired steam boiler (installed in 2015 by previous owner to replace an Oil fired boiler ) needs to be filled up every 2-3 days - which I know is not good. I’ve traced every pipe I can, including all crawl spaces at least 3 times. I know there’s a chance of an underground leak but it would need me to remove half the house to find it. Hence, I though about having a steam pro diagnose if there’s a crack in the heat exchanger/boiler as I read that steam would vent up the chimney if so. I’ve heard that it requires draining the boiler and using nitrogen to diagnose a small crack? A larger one would I guess be visible.

Problem #2: 2 upstairs radiators get little or no heat.

Everything heats up quickly except 2 upstairs radiators (1 very small one in the bathroom gets no heat, 1 larger one in the rear bedroom gets very little). I can only get heat in the bathroom if I turn off all the downstairs rads. (impractical). However, I’ve noticed these 2 radiators are the only ones served by smaller 1 inch iron pipes which travel horizontally in the basement floor for 8-10 feet before rising about 15 feet to the second floor and then horizontally again before they reach the radiators. I can hear gurgling, water hammer type sounds by those rads. and perhaps the final horizontal leg before those radiators may be back pitched slightly (i cannot see as the pipes are hidden), but the pipework to get to those rads. in my 1891 house is so convoluted and would cost a fortune to access and reinstall. The rest of the rads get served by 1.5 inch pipes that pretty much go directly (vertically) to the radiators without these twists and turns and they work fine. It would require major reconstruction to change the hidden piping so I’ve invested in supplemental (i.e. electric plug in radiators) heat in those 2 rooms. I wanted to get your perspective on anything else I could try to get more steam heat to those 2 rooms. All the radiator vents have been recently changes to Gorton (mix of 4,5,6, C, D). My only other observation is that the near boiler piping header is only 22.5 inches (not the minimum 24 inches) above the mid-level of the sight glass (water level) so I may have some wet steam. The technical staff from Weil McLain didn’t see this as a reason for getting no heat to the bathroom radiator. It has a lot of air to vent given the horizontal and vertical distances to those rads.

Thanks for any advice you can give.


  • FredFred Member Posts: 6,316
    edited January 12
    On those two radiators, raise them up a half inch or so and then repitch them bach towards the supply pipe. Raising them will add pitch to the horizontal pipes under the floor. No need to replumb them.
    As for the water loss, It is most likely a return, under the floor is leaking. You can abandon those and repipe the returns above the basement floor. Just make sure you keep those pipes well below the Normal water level in the boiler. Probablky a job for when the weather breaks. Great contractors, oif they service your area include @EzzyT , @Dave0176 @JohnNY
  • Jamie HallJamie Hall Member Posts: 7,894
    Those long one inch runouts are very problematic -- they really are too small. Are they, at least, accessible? Or are they hard to get at too? If they are accessible, I'd seriously consider the possibility of increasing them to inch and a quarter or inch and a half, then going up with what you have. And, possibly increasing the pitch on them at the same time -- although that would involve messing with the end of the vertical riser which could be difficult.

    As for the water loss... nitrogen? Give me a break, man! If you have a leak in the boiler above the water line, go outdoors when the boiler has been running for a while. If you have a significant leak you will see beautiful billowing white "smoke" (actually steam!) from the chimney. If there's no leak, you will still often see a little white smoke -- but that's normal.

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

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • acwagneracwagner Member Posts: 125
    Remote chance for this, but have you measured your radiators total EDR and compare it to the boiler capacity? In most cases boilers are oversized, but you possibly could have an undersized boiler.

    Also, besides your two problematic radiators, do your radiators all heat up roughly at the same time?

    Burnham IN5PVNI Boiler, Single Pipe with 330 EDR
    18 Ounce per Square Inch Gauge
    Time Delay Relay in Series with Thermostat
    Operating Pressure 0.3-0.5 Ounce per Square Inch

  • FredFred Member Posts: 6,316
    He hears gurgling and a little hammer by those two radiators, both indications of water near those radiators. I believe raising them up a bit and then re-pitching them will solve the problem.
  • IanFIanF Member Posts: 5
    Fred, Jamie and AC - thanks for the really helpful suggestions. Fred - and thanks for the recommendations on steam pros for when the weather breaks. These 2 radiators are of the recessed type. The idea of raising them and re-pitching sounds like a practical step but the small one in the bathroom has no radiator valve (i.e. its piped / connected directly) so would someone need to cut the horizontal supply pipe to it then raise and then reconnect it?
    Fred - re: your comment: "Raising them will add pitch to the horizontal pipes under the floor." Do you also mean raising the pipe (angle) as well as raising the radiator or is that the same thing?
    My only concern when doing this "raising" is whether there's a chance of the hidden horizontal supply pipe joints cracking and creating a new leak? The horizontal pipes that connect to them are hidden under the bathroom floor and under the new wood floor with no easy way for me to see/access them other that right at the radiator connection.

    The downstairs radiators are more accessible via the basement (sheetrock) but i don't have a problem with them.

    Answering questions you raised:
    - Yes all others (upstairs) heat up at roughly the same time with no problem.
    - No I haven't measured total EDR v builder capacity but can seek advice from the contractor who helps with this
    - Yes, i did look outside for white smoke (steam) coming out of the chimney, and I can see some but it's so cold at present, it's hard for me to tell if that's normal. I guess I'll need to look when it's warmed up a bit.
    - It's a one pipe system so I thought the supply and returns were the same pipe? All the supply/returns are above the boiler - the only two "returns" I cannot see/access (and these are not connected to the 2 problem radiators) are at the entrance to my house where it seems like they disappear horizontally above the basement subfloor but underneath a tiled entrance floor to my house - surrounded by concrete block. ie. very hard to get to, to check. I don't understand what you mean by "water loss is most likely a return under the floor is leaking, you can abandon those and re-pipe the returns under the basement floor"? I'm not sure how I would abandon these as they act as both the supply and return pipes (1 pipe system)?
    - The one inch return verticals run behind the walls, so are not as accessible as I'd like.

    Thanks for all your help guys, Ian.
  • IanFIanF Member Posts: 5
    OK, a quick follow up. I've checked the chimney and there's no white smoke coming out of it. However, I've noticed that the steam radiator vents hiss a lot and when I took a few off (after the rads were cold) I notice that there's quite a bit of water in them. Could "wet steam" cause lead to
    water loss?
  • FredFred Member Posts: 6,316
    @IanF , by raising the radiator a half inch or so, I mean raise it without disconnecting it from the piping. The goal is to raise the radiator still connected to the supply pipe and that will add some pitch to the supply pipe as well. When raising it, don't put any stress on the pipe, if it appears it is hitting a joist or the underside of the floorboard.
    On a one pipe system, the supply pipe is not at floor level. Supplies are above the boiler. Wet returns are at or below the floor level. That is where you will most likely loos water, from a wet return that has rusted through. If the water loss is not visible on any of the above grade piping, it is likely in a section of pipe that may run below the basement floor. When I said "Abandon" the below the floor piping, I meant, if you find that that is where a leak is, you can reroute the wet return at or above the basement floor as long as you keep it below the boiler water line. Beats tearing up the basement floor.
  • IanFIanF Member Posts: 5
    Thank you, Fred. I appreciate all these clarifications. I've checked all the wet return (which are visible) and have found nothing leaking. I now understand what you mean by raising the radiator. I'm enclosing a photo of it (see the piping). I'm not sure if this is of the type you can just try raising or whether that copper pipe makes it challenging. Unfortunately - the horizontal run (under the tiles) to this rad. is only about 2.5 fee, then it drops from second to first floor) so I guess I'll need a steam pro. to help me determine if there's flexibility to raise it without stressing the pipe. Best, Ian
  • IanFIanF Member Posts: 5
    ...the horizontal run beneath the tiles to this radiator is only about 2.5 feet then it drops vertically about 15 feet - behind the living room walls to the basement where it goes horizontal again. I said it was convoluted...
  • FredFred Member Posts: 6,316
    With those 3/4" slats under each leg, it looks like someone already raised it once.
  • HarryHarry Member Posts: 47
    Although it seems unlikely the boiler has an internal leak, given its age, it's easy to check. Just shut the boiler off and manually overfill it. You can check the level by opening the safety, if you like, then add enough more that you are starting to get up into the steam header. In cases where there is corrosion above the water line this is usually a tip off. Water will start leaking from the sections to around the burner and onto the floor. If so, there's your leak (Afterward, make sure to drain it back to an operating level and boil that water asap). If, on the other hand, you had a buried wet return, that'd be my guess. (Nitrogen! Really?)
  • HarryHarry Member Posts: 47
    Of course don't put ice-cold water into a hot boiler!
Sign In or Register to comment.


It looks like you're new here. If you want to get involved, click one of these buttons!