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leaking steam radiator

targetmantargetman Member Posts: 105
Any way to fix an old leaking rad?


  • nicholas bonham-carternicholas bonham-carter Member Posts: 6,540
    rad repair

    first determine from where the leak comes, and like a leaking roof, it can be difficult to pinpoint the errant joint. if it is the air vent on a 1-pipe system rad, then the fix is simple. like the air vent, a leaking valve packing nut could be repacked with graphite string; however a bad nipple between the sections would be more difficult to repair. it may be easier to find another radiator of a similar size, and replace it, including a new valve, and spud. make sure the valve is completely open, so as not to collect water.

    some people have been able to use automotive stop-leak with some success.--nbc
  • icesailoricesailor Member Posts: 7,265

    My old High School Auto-Shop teacher used to say "You Can't Buy A Mechanic In A Can".

    You can try automotive stop leak or preparations for hydronic systems. I've never seen them work. Replace what is leaking for a permanent fix if it isn't a packing nut or a threaded connection.
  • SteamheadSteamhead Member Posts: 11,378
    edited May 2011
    If the leak

    is at the joint line between two sections, you probably have a rotted-out push nipple. The push nipple is a slightly tapered tube that forms the joint between two sections, and these sometimes rot out. It will be necessary to take the radiator apart, find a replacement push nipple and reassemble it. If this were a plain radiator, it might be easier to just find a whole new one, but an ornate beauty like that is worth the effort.

    Is there a brand or model name on that radiator? Look on the end sections, around where the pipes connect.

    Then, we need to address why the nipple rotted out. I suspect acid condensate, which is usually caused by inadequate air venting.
    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.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 6,540
    a nice 2-pipe vapor system radiator

    that is worth saving!

    can you take some more pictures of the threaded rods which appear to hold the sections together?--nbc
  • Jamie HallJamie Hall Member Posts: 6,694

    you can take it apart, it's not that hard.  It's that first step.  If it has threaded rods, undo the nuts -- this is not as easy as it sounds if the threads have a few layers of paint on them, but it can be done.  Don't force it.  The rods won't take much torque (ask me how I know).  Get the threads nice and clean, and use some sort of penetrating oil.  Once the rods are free, lay the radiator down and split the sections at the leaking joints.  Again, easier said than done; they won't want to come apart.  Lots of ways to do it, so whatever works -- but you will need to work both top and bottom.

    Then, as Steamhead says, you will probably find a rotted nipple.  If you have the make of the radiator, there are firms which can machine you a replacement (I don't have the contact -- somebody, help!).  However, if all else fails you can simply rotate the offending nipple 180 degrees, so the rotted part is on the top.  Then around the joint -- but NOT touching the nipple -- run a bead of red RTV silicone.  Just enough so that when the sections are pulled back together it will seal.  Don't use too much, or it will get where you don't want it.  Remember: you are not trying to seal the nipple, which is a machined fit, but the sections to each other.  Yes, it's a kludge.  Yes, it does work for low pressure (residential) steam.

    Then pull the radiator back together -- again, this may take some persuasion, but make sure that the sections are back tight.  Put the rods back in and the nuts back on; they should be just beyond finger tight -- don't reef on them (see paragraph one!).

    And you should be good to go...

    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
    Rebuilding Radiator.

    Hi- Here's a article of Dan's on radiators which might be of interest to you.

    The article has a  source for push nipples Jamie mentioned in his post.

    Oneida County Boilerworks

    (315) 732-7914

    Take your time and use a lot of patience when taking the radiator apart. I used both wooden wedges and spreader clamps when taking disassembling the sections. Following Jamie's advice, apply pressure evenly to both the top and bottom of the sections you wish to get apart and when reinstalling the rods, don't over tighten them as the sections when they heat up, will expand and put too much tension the rods and cause them to break.

    It's a nice radiator and would be worth fixing.

    - Rod
  • BRIANJBRIANJ Member Posts: 118
    edited May 2011

    Those are Richmond Radiators. You can find out about them in the Library. Looking at the length of the rods in your picture it looks like someone cured a previous leak by removing a section of the radiator. At some point in time I had the same problem. But back then the knucklehead decided to remove two cells from the radiator rather than replace the push nipples. That shrank the rad from 26 cells to 24 with a 8 inch pipe connecting to the valve. Funny thing is it still leaks and I haven't gotten around to ordering the push nipples and can't find another Richmond radiator to extend radiator to its original length. Oneida will need the measurements of the ends and middle of the push nipple to size it correctly. Good luck!
  • Charlie from wmassCharlie from wmass Member Posts: 3,922
    Oneida wants you to mail them

    at least one push nipple. I have one on my desk now I need to mail to them for replacement. It is from a two section steam only radiator.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • ChukBuXChukBuX Member Posts: 1
    edited February 2014
    OoooH, them nipples!!!

    We had a 20in tall x 12 in deep x 60 in long radiator (24 fins).  Six fins were cracked and one was shooting water, after a recent warm day, following a ~12 DegF week.  I read all these entries, and found that the Randomness of radiator nipples was the #1 driver.

    I cracked the six bad fins out using plastic shims on one side and an axe with a metal chisel alongside, on the other, alternating what I smacked with the 5 lb hammer (that's when I found out that there are 2 connecting rods on top and another (!) rod at the bottom)

    I tried to remove the nipples but could not get them out with a pipe wrench (which ruined the surface) or with a sledge & flat punch to "push" them out from behind...

    So, I started taking off each "good" segment just to see what nipples came with them.  You can turn them upside down, if needed.  I drew pictures of the 5 good segments I had pulled with no luck, in any variation.  Then I realized that the left "end" now had a "top" nipple and the right end now had a "bottom" nipple, so the 24 fin radiator is now like 13 fins wide.

    Home depot is so lame I had to remove fittings, starting at the radiator, replacing them with leakers (not the best place to go for old technology, or even new. IMHO), so far, even with slathering with pipe dope on all threaded fittings  -- tightening leakers 1/8 turn each hour.  When they stop leaking, will try hot water heating.
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