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Unique radiator (pic included) and proper pitch assistance needed

Hey guys.  My landlord had a plumber replace the ridiculously small, steam, one-pipe radiators under the 2 windows in my apartment yesterday.  The replacement radiators that he brought are much larger and I'm sure will heat the space better, but they have connections on the inside instead of on the outside however.

As a result, it seems physically impossible to pitch the radiator toward the inlet pipe and not have the last few inches of the straight pipe pitch upward instead of downward.  In fact, I can't think of a setup where this type of inside connector would ever work.

Will the condensation drain properly?  Should I:

1. Leave it pitched as is despite the very slight upward slope where the pipe connects?

2. Level the radiator which would fix the slight upward slope where the pipe connects, but might not encourage draining from within the radiator itself.

Thoughts?  I'd appreciate a few opinions.

Thanks everyone!


  • Hap_HazzardHap_Hazzard Member Posts: 2,263
    My opinion?

    I think that's the ugliest radiator I've ever seen!

    I'd be tempted to just step on that pipe and see if I can bend it a little without breaking it. Copper is pretty ductile. Plus, you can see how good the solder joints are.
    Just another DIYer | King of Prussia, PA

    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • JStarJStar Member Posts: 2,752

    No good. good.

    You can't win in this situation. The piping arrangement does not allow the radiator to be pitched in any direction. I would try to lower the copper pipe, or have it redone to turn downwards immediately out of the radiator and then run the pipe to the left.

    Is that 3/4" copper?!
  • jkozlow3jkozlow3 Member Posts: 18

    Yeah, 3/4" copper.  Why?
  • JStarJStar Member Posts: 2,752

    Steam capacity charts don't list 3/4" pipe for one-pipe steam. 3/4" pipe just isn't large enough to handle steam and condensate moving in opposite directions.

    Are there any problems with this radiator? Noises, hissing?
  • jkozlow3jkozlow3 Member Posts: 18

    Well, I had 2 very small units under each of the windows and they both had some hissing, banging and gurgling when in use, yes.  They didn't get warm enough and they were daisy chained together via 3/4" copper pipe which went out of the far side (not the inlet side) of rad #1 and went to rad #2.I don't think this really allowed proper drainage and definitely seemed a bit jerry-rigged to me.

    The plumber said that my living room wasn't warm enough because the rads were grossly undersized (they were - smallest I've ever seen).

    He replaced both of the units with these larger ones and rad #2 isn't getting any heat because he hooked it up the same way as the old setup which I believe is simply causing rad #1 to drain into the pipe connecting the 2 radiators.  He was supposed to come back tomorrow and put a tee in the 3/4" copper which would then cause the radiators to act independently instead of as one long unit (since they're connected).

    I'm guessing that based on your comments about 3/4" being insufficient that this is probably yet another bad idea however.

    Perhaps I'll see if he can just order me a larger unit that goes between the two windows and connect it directly to the main (larger) pipe coming up from the floor instead and call it a day.
  • jkozlow3jkozlow3 Member Posts: 18
    edited December 2011
    By the way...

    By the way, if I do ask him to put a single unit in the middle of the 2 windows connected to the riser pipe, what size pipe should he run to the radiator? (3 feet away from where the riser pipe comes out of the floor)

    Thanks again!
  • icesailoricesailor Member Posts: 7,265
    Sunrad Radiator

    Simply stunning.

    What were they thinking?
  • AbracadabraAbracadabra Member Posts: 1,948
    edited December 2011
    use a street el out of the radiator

    use a street el out of the radiator to minimize the amount of condensate remaining in the radiator. the longer the nipple is that comes out of the radiator, the more condensate that will reamin in the unit.

    oh and if you must leave that 6" piece in there, perfectly level would probably work best.
  • JStarJStar Member Posts: 2,752

    It depends on the amount of radiators connected to that pipe. He needs to know the EDR of the radiator, then match the piping to handle the amount of condensate produced.

    What size is the riser pipe? Bigger than 3/4"?
  • jkozlow3jkozlow3 Member Posts: 18
    full pic

    I'm attaching a pic of the entire setup, which needs to be changed (plumber is coming today).  Nothing is going to the far radiator at the moment, as I believe rad #1 is simply draining into the line that connects to rad #2.  This is how the 2 old units were connected and he simply followed the same setup when putting the new units in.  Since this isn't working, he was going to install a 3/4" tee today which would feed both units separately.

    The riser is quite large in comparison.  Not sure what size, but it's a much fatter pipe. After the valve, the pipe is immediately reduced to 3/4" and that pipe is routed to each of the two (identical) radiators which sits under each window - 4 feet apart.

    From what you're saying, 3/4" might not be sufficient in the first place.  Plus, with a tee, I imagine the steam will take the path of least resistance and feed radiator #2 first/quicker since it would have to take a sharp turn to feed rad #1.

    As for EDR, if I had to guess, I would say each of the 2 units is around an EDR of 25 since they are 20" high, 9 sections and 5 inches deep (no visible columns or tubes as that you can count).  So 25 each, 50 total for the room which seems about right based on what I've read online for the amount of square footage that needs to be heater here.

    What size piping should he be using?  Is a tee in the 3/4" pipe to feed both units with it's own pipe going to work well?  Is there a better way?  This particular setup is seriously cramped for space.

    Thanks again!
  • SteamheadSteamhead Member Posts: 13,817
    That will NEVER work!

    The legs of those Sunrads are filled with water. So the pipe connection between the two will always be filled with water.

    Have them call a real Steam Man in, to find a way to tie both rads in directly to the pipe coming up out of the floor, using at least 1" pipe. That's the only way these two rads will work.
    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.
  • jkozlow3jkozlow3 Member Posts: 18
    edited December 2011

    Yeah, I had my suspicions about the flow between the two radiators right away and quickly figured out that this setup won't work by the fact that water is draining from rad #1 into the bridge pipe and I can hear it sloshing around in there.  Obviously, the far radiator never gets hot as a result.

    In the meantime, is there a way this setup might work with the existing 3/4" pipe and a tee connector and separate pipe going to each of the radiators?  I'm guessing that this will at least work OK if not ideally, providing we can figure out how to maintain a proper pitch EVERYWHERE.  As you can see, there are a lot of bends and not a lot of clearance to raise radiator #2, so that might be a challenge.

    I don't know that my landlord is going to want to pay for yet another person (steam expert) to come out and work on this system - she'll probably just tell the plumber to make it right since she's already going to have to pay him for his efforts.  That's why I'm looking for ideas to give to the plumber.

    I appreciate the continued assistance!
  • SteamheadSteamhead Member Posts: 13,817
    3/4" is too small

    for a horizontal runout to that size rad. I've seen it work on some extremely small rads- under 12 square feet or so- but not on something like that.

    It needs to be repiped. Period.
    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.
  • JK_3JK_3 Member Posts: 240
    I looked at this job today

    Sometimes I am amazed at what some "pros" will do and then swear it should work, Then I remember that before I met Dan and became part of this group I was one of them. I did it ,as Dan explains because that was the way I was taught.

    As this job goes I am again caught between doing it right and trying to make what someone else did to work. I believe that there was originally a 1 1/4" steel finned recessed rad here. It was replaced with 2 Sun-rads with the connecting pipe run exposed. No heat loss was done. The floor was never opened so every thing needs to be done above floor and around walls. I intend to re-pipe in black 1 1/4" with steam fittings. I will eliminate the existing valve(with reducer but not union) with a 90 set to a Tee. Each rad will have new valve set and the vents will be a 4 on the first rad and a 5 or 6 on the second( still running the numbers). It wont be pretty but is will work. If anyone has any other input I am open to it . It is always great to collaborate with you guys and I always welcome the input. 
    Life is Good !! Enjoy it !!
  • icesailoricesailor Member Posts: 7,265
    Sunrad Connections:

    I installed more than a few Sunrad radiators back a long time ago when I worked for my old dead boss.

    As I remember, I always had to use 1 1/4" Black Reducing Bushings to get down to 3/4" or 1/2" Copper on the hot water radiators we hooked up.

    This isn't in any way a solution for a less than perfect installation, but if the riser coming up through the floor that the original radiator was connected to is 1" NPT, a 1 1/4" X 1" Bl. Red. 90 would at least give a better size for flow to the two radiator on one pipe. There may be pitch issues that I can't see but it might help the situation.

    I was under the old impression that those Sunrads were designed for Steam OR Hot Water. I only connected them as hot water.

    Just a thought. Tell me it won't work and I won't argue with you. But it's something to try.
This discussion has been closed.


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