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Steam Radiator Spewing Water

klalklal Member Posts: 10
I have an issue with a single radiator (copper fin convector in a steel enclosure) on a one-pipe steam system which I ran (yes, not a professional) several years ago to a finished sun room (former porch). I ran this radiator off an existing riser from the supply main, in a wye configuration (yes, I know that it needed a dedicated riser, but at the time, due to budgets, it was either try an improper setup or no heat in that room at all). The riser runs from my toasty basement under the fully enclosed, but not heated crawlspace of the sun room, about 7 feet, and comes up through the floor on the far side of that room (the exterior wall side). The enclosed space under the room is cinderblock, and the riser runs through a 2 x 12 bay insulated with fiberglass batt insulation, and enclosed in with 3/4 plywood and caulked. So essentially, the bottom of the room is closed and insulated, not open to the elements, but is unheated. It always took the heat longer to get to this room, and when it did (with consecutive heat cycles), it spewed water from the valve. We replaced our boiler a couple of years back, and replaced all of the valves with Gortons that were specified by Gorton technicians to achieve proper heat based on distance from the boiler. That improved the situation a bit, as more heat was sent to the sun room, and although the radiator still spewed, it did improve somewhat. A few days ago, I had my plumber cut the supply main and install a proper dedicated riser to the sun room, eliminating the wye and returning the shared line to the original line it was split from, so now there are two dedicated risers, as they should have been from the start. Unfortunately, I am still getting water coming out of the valves, and although it seems to have improved again, spewing is still spewing, and I'd like it to stop. The radiator is extremely pitched (no mistakes about that) back to the radiator valve, and the valve shoots straight down into the floor to a 45 elbow and then a pitched run of about 7 feet to the newly added riser to the main. I originally thought that the condensation from the shared line was pushing water into the radiator, so instead of it running back to the supply main, it remained or even was drawn into the radiator. Now that they're separate, I'm not sure if the water is generated by the (colder) pipe inside the sun room floor. Any thoughts or things that I can try to troubleshoot would be greatly appreciated.

Comments

  • Jamie HallJamie Hall Member Posts: 12,865
    Fin tube is always difficult on one pipe systems. That said,, pitch -- and size -- are critical. You don't mention the size of the pipe under the sun room. Be sure that it is at least one size larger than would normally be used for the EDR of the radiator -- and that it is pitched at least 1" from end to end -- and I'd rather see 2". Is the pipe totally enclosed in the fiberglass insulation under there? If not, it should be insulated -- at least 1" insulation.
    Br. Jamie, osb

    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
  • FredFred Member Posts: 8,422
    A couple thoughts come to mind, for me:
    1. What size is the supply pipe? Is it 1" or less? it may not be large enough to allow steam and condensate to flow, in opposite directions at the same time.
    2. Is the sunroom a step down? If so, how high is that convector above the boiler water line?
  • Big Ed_4Big Ed_4 Member Posts: 1,349
    Pipe the fin tube two pipe and move the vent on the return line before it drops back down to the wet return or steam trap . Or change the fin tube to a radiator .. You can and should also insulate the supply pipes...
    I have enough experience to know , that I dont know it all
  • SteamheadSteamhead Member Posts: 13,825
    How long is the element in that convector? You may need to add a return line and pitch the element down to the return connection, to drain the condensate.

    What type of radiation does the rest of the system have?
    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.
    https://heatinghelp.com/find-a-contractor/detail/all-steamed-up-inc
    Hap_HazzardCanucker
  • klalklal Member Posts: 10
    Gentlemen, thank you for your quick and comprehensive replies. I will try my best to answer the questions you have to the best of my abilities and knowledge.

    All but one radiator in the house are the original copper fin tube convectors that were installed with the (sadly retired) American Radiator Co. Ideal Red Flash boiler (I think it was a 1929 model, if I remember correctly). The only replacement is now cast iron, as the original had pinholed/cracked and couldn’t be repaired. The cast iron replacement is the unit that this spewing one was previously wyed to.

    The supply pipe is not individually sleeved inside the bay under the sun room, rather it is between the layers of fiberglass batting, I think I made a sandwich with two pieces. I’ve even considered removing the plywood and having spray insulation applied to the underside of the sunroom.

    The size of the pipe is 1”, as are the other 4 that run to the first floor (one level above the boiler in the basement), all the second level risers are (I think) 1.5”.

    The convector in the sun room is 30” long, 5” wide, 5” deep, and is inside of a steel enclosure, about 5.5’ feet above the water line of the boiler. It is pitched 1” from end to end, but can be raised more if needed, the valve is a Gorton #6. See attached photo.



    As I mentioned in my original post, the radiator goes into the floor, to a 45 elbow, to a straight run of pipe. I didn’t mention that it then steps down through a 1” street elbow which goes directly into a 1” 90 elbow, to a straight run of 1” pipe approximately 24” to a union, nipple, 45, nipple and back to the supply, see attached photo, second pipe from the foreground. Could the street elbow be causing the logjam of the condensate and steam since it narrows?



    Again, thanks for all of your help, I hope I've given you enough details.
  • retiredguyretiredguy Member Posts: 221
    I do not want to break your bubble but I would call a steam guy to check the whole system. The 1" supply piping to that spewing convector is way too small to be used on a 1 pipe system. You may want to follow the advice of @Big Ed 4 or @Steam Head and add a return line or change the convector. I recently stayed at a B&B that had a 1 pipe steam system where a local contractor replaced all the standing cast iron rads with baseboard C. I. Burnham Base Ray or equivelent radiation. Now the system hammers and heats poorly.
  • FredFred Member Posts: 8,422
    That pipe in the foreground seems to be pitched the wrong way. Are you getting any hammer or gurgling from that run?
    A 1" pipe should be able to handle about 25EDR. What is the EDR rating on that convector?
    The Gorton #6 may be a little too aggressive with the 1" pipe. You might try a #4 or #5. It may slow the steam down enough to let the condensate flow back to the main.
  • klalklal Member Posts: 10
    The original piping, back to when the house was built is 1" to the radiators on the first floor, no other radiators exhibit any problems, no water hammer, nothing—just this one convector. I'm guessing that it was built to proper specs, the old men of steam knew what they were doing back then.

    As for the pitch of that foreground pipe, that's an optical illusion from the photo. It is pitched back to the supply main, and it heats with no issues. Although the foreground pipe is further away from the riser in question, it heats quicker/first, but I am guessing that is due to the fact that the riser with the issue is colder since it travels through an unheated space.

    I don't know the EDR on that convector, it is two rows of fins that are 30" long, 5" high and 2.5" deep each. The steel enclosure is 32" wide by 20" tall.

    I can try and swap out the Gorton #6 for a #4 and see how that affects it. Do you think I need to remove the street elbow that ties into the 90 elbow (far right of the picture) and replace it with a 90 elbow, small nipple, 90 elbow? The street elbow does narrow the diameter of the riser somewhat, not sure how much that impacts it, I'm guessing every little bit counts.
  • FredFred Member Posts: 8,422
    edited March 22
    @klal said: "The original piping, back to when the house was built is 1" to the radiators on the first floor, no other radiators exhibit any problems, no water hammer, nothing—just this one convector. I'm guessing that it was built to proper specs, the old men of steam knew what they were doing back then."

    Don't bank on what the Dead men of Steam did back then. Circumstances were different. Boilers ran on coal and ran constantly from the beginning of the season through to Spring. Steam was much slower moving through those pipes and at lesser volumes so condensate could flow back much easier. Today, with gas and/or oil fuel, boilers run in bursts and with a lot of steam being generated and flowing at much higher volumes, leaving less room for condensate to return during the heating cycle.
    Try a slower vent first. I doubt that street elbow is much of a problem. Insulation and the 1" pipe may be.
  • STEAM DOCTORSTEAM DOCTOR Member Posts: 1,164
    Don't know.if anyone mentioned this but mayne supply valve is not fully open
  • Jamie HallJamie Hall Member Posts: 12,865
    "I don't know the EDR on that convector, it is two rows of fins that are 30" long, 5" high and 2.5" deep each. The steel enclosure is 32" wide by 20" tall."

    You have almost all the data you need to calculate the EDR. What you are lacking is the number of fins. If your fins are 5 inches by 2.5 inches, then you have 1 EDR for every 6 fins -- at least closely enough for government work. Just count them up...
    Br. Jamie, osb

    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
  • klalklal Member Posts: 10
    True, I was told my Red Flash was originally coal, converted to oil, and finally to gas, and it did run nonstop. When I had the boiler replaced, I thought there was something wrong when the steam was achieved and the boiler cycled off, and then on again when necessary.

    Switching over to a #4 vent will be my next test to see the impact, insulation will be next.

    The radiator supply valve is fully open, just double-checked.

    As for the EDR, the convector is two sections, with fins on either side of the two halves. Not sure if we're just looking at the total number of consecutive number of fins when facing the front of the enclosure (43 ÷ 6 = 7.2), or each physical fin, front, inside front, inside back, back (43 x 4 = 172 ÷ 6 = 28.6).

    I'm getting quite the education, and as an educator, I appreciate everyone's knowledge and patience, really do.


  • Big Ed_4Big Ed_4 Member Posts: 1,349
    I noticed there is no insulation on any of the supply pipes . Without it adds so much more condensate (liquid water) with in the system . Your system was original designed with pipe insulation for a reason .
    I have enough experience to know , that I dont know it all
  • klalklal Member Posts: 10
    Yes I would like to insulate the pipes, the basement is way too hot and that should help with that too. What is the best insulation for the steam pipes and risers? Originally I had asbestos, which was abated. And there was a section that the former homeowner covered in foil wrapped foam, which is useless. I've been told paper wrapped fiberglass, and someone said there is a cardboard wrapping, not sure if they meant the fiberglass. Recommendations?
  • Big Ed_4Big Ed_4 Member Posts: 1,349
    edited March 23
    The old asbestos insulation was corrugated.

    .
    I have enough experience to know , that I dont know it all
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,059
    @Kial

    I am really surprised no one mentioned getting rid of the 2 90 degree elbows. (unless i missed it) I see no need for them and they are surely causing part of your problem. If you must have elbows there they should be 45s not 90s. Looks like that could be a straight run to me

    Converting to two pipe is a better fix if you can get to a return line. 1" pipe can't take much of a back flow of condensate
  • Jamie HallJamie Hall Member Posts: 12,865
    On the EDR. What you want to determine is the actual total surface area of the fins (it really isn't mysterious -- though we often seem to make it so!). So it seems to me that your 28 figure is probably not far off.

    Which is a lot for a 1 inch pipe -- particularly since copper fin tube condenses steam a lot faster at first than cast iron with the same surface area wouold.
    Br. Jamie, osb

    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
  • JUGHNEJUGHNE Member Posts: 6,932
    Is the inlet valve on the problem convector the same on the rest of the system? If it is a globe valve then possibly water could not drain back.
  • klalklal Member Posts: 10
    At the least, I will convert those two 90 degree elbows to 45s. I'm not sure I can get a single run, but I will try.

    Hopefully the insulation, changing the elbows helps the 1 inch pipe situation.

    As for the inlet valve, it is the same original valve used on every other radiator in the home. Not sure if it is considered a globe valve.


  • Jamie HallJamie Hall Member Posts: 12,865
    It is at least a variation on a globe valve -- but set vertical like that, it won't trap water unless the washer (if it has one -- most do) has come off the stem.
    Br. Jamie, osb

    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
  • JUGHNEJUGHNE Member Posts: 6,932
    For piping, you could use a longer nipple riser on the main and maybe then a straight shot...the more slope the better.
  • STEAM DOCTORSTEAM DOCTOR Member Posts: 1,164
    edited March 25
    > @Jamie Hall said:
    > It is at least a variation on a globe valve -- but set vertical like that, it won't trap water unless the washer (if it has one -- most do) has come off the stem.

    This should be checked out. Washer might be partially or completely off the stem.
  • klalklal Member Posts: 10
    I will definitely check the valve. I'll remove the handle/stem and see if there's an old washer lodged in there. Right now that valve doesn't need to close, so even if I can't find a replacement weather immediately, I can live without it. I can also try a longer nipple on the main (didn't even think of that, I've been fixated on the other side the whole time—maybe that's why I'm not a very good amateur plumber), but I have to get some nipples and elbows first. Thanks gentlemen, you really are helpful.
  • klalklal Member Posts: 10
    Revisiting this thread. Long story short, I opened up the crawlspace to check for pitch (it is pitching properly) and had my plumber eliminate the elbows to the main so it is a straight run (there are a few elbows between where the radiator pipe goes through the floor and connects to that improved run, I guess it would be a "swing joint"? Runs about a foot if I remember it correctly). The elimination of the elbows near the main improved the situation, but there was still some spewing. I also did some valve swapping which helped, but again not fully resolved.

    Before I close up the crawlspace again, I was wondering if I could get some advice. Do I make the change to a 1.25 pipe from the 1 inch, and if so, would that improvement be defeated if the radiator valve is still 1 inch as is the t on the main? I know 2 inch was suggested, but I'm not sure I can get it to fit within the crawlspace while maintaining pitch due to the size change. I know the increase in pipe size is to accommodate the steam and the condensate streams, so that the steam pumping up doesn't carry water with it, but will there be a "bottleneck" if the radiator and main are the 1 inch, and still pushes the water?

    Regardless of the pipe diameter, I will be getting the fiberglass pipe sleeves, as high of an insulation value as I can to cover the pipes. The rest of the bay will be fiberglass batt insulation, and finally sealed with plywood.
  • SteamheadSteamhead Member Posts: 13,825
    Increasing the pipe size would be my next suggestion. A horizontal pipe, even pitched properly, cannot handle as much EDR as a vertical pipe.

    Failing that, I'd change from fin-tube to a cast-iron radiator.
    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.
    https://heatinghelp.com/find-a-contractor/detail/all-steamed-up-inc
  • BobCBobC Member Posts: 5,109
    Fin tube and steam don't get along well because they produce a lot of condensate and the steam has to fight it's way past the returning condensate. They should be vented very slow and if all else fails increasing the pipe by on size may be necessary.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
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