Looking for input on my one pipe system

a2shutt

Per Crash2009's suggestions, I'm starting a new thread looking for some input on my (maybe!) unique system.



I've got a one-pipe system with a newer (07) Burnham IN9. The system works well enough, but doesn't heat very evenly. It's in a 7 unit apartment building.



Rather than being a traditional or counterflow system, my steam mains are high at both ends (vents and boiler) and pitch toward the center of the main, where they end up in a wet return. Anyone have experience with this sort of setup?



There is also the puzzle of a plugged riser, which you'll see in the photos. Both steam mains come off the same riser (out of the header), but it appears that they used to be on separate risers. The plugged riser is newer pipe, so they must have done it when the boiler was swapped. Any feedback on this situation would be appreciated as well.



We've talked about main venting, and Crash has suggested 3 Gorton #2s on the bottom main (on the diagram...that's the front of the building) and 1 Gorton #2 and 1 Gorton #1 on the top main (back of the building). Right now there is a Hoffman 75 on each.





Crash has very graciously catalogued my photos better than I did, and he's going to post them in a response to this post.



I've posted a diagram showing pitch to get started. Green is the current main vents, red is the steam pipes, blue is condensate, and the black arrows indicate pitch. The purple circles indicate risers to radiators.

crash2009

Here

are some additional pictures.  Dave and Steamhead have allready commented in a previous post.  http://www.heatinghelp.com/forum-thread/139846/How-are-we-supposed-to-vent-this-thing

Rod

Possible Improvements

Hi -Looking over the drawings and pictures I was wondering if the system might not be improved with adding individual drips to the combo steam mains, one drip on the lowest point of the counterflow main and another on the lowest point of the parallel steam main. My concern would be the affect of the possible collision of the two condensate streams entering the single drip.  Not seeing the piping I don't know how easy this would be to do and would depend on deciding whether the single drip might actually be causing a problem. Initially I would think that locating the main vents where Steamhead suggested would be the major priority



The other thing I noticed was in the picture of the boiler piping. One riser coming off the header is connected to both steam mains. It would seem very easy to use the plugged riser so each main would have its own connection to the header.

- Rod

a2shutt

thanks

for posting these, crash. Sorry I didn't see that you started a new thread last night until just now.

a2shutt

I think

I'm going to go talk to the guys who installed it and find out if there is a reason why they plugged that riser and pulled that steam main off the tee. I felt them today and the main coming off the side of the tee was definitely cooler than the one off the top of the tee, but there seems to be plenty of heat. Any chance this boiler is oversized? 280k btus for about 3500 sf of living space with around 18-20 radiators.



Steamhead-I'll get rid of those vents on the returns. I've been worried that they are directing steam down the return instead of the main. One has been sticking anyway and blowing steam all over the place. Actually, the other one has a shut-off below it so I guess I can just turn it off for now.

Rod

EDR Sheet

Hi - Attached is a sheet which will help you figure out the EDR of your radiators so you can determine if or not your boiler is over sized.

- Rod

a2shutt

I had to do some guesswork

but I'm only coming up with about 150k btuh. Even if I'm underestimating, it looks like they way oversized it. Maybe that's why they fed both steam mains off one riser? I should ask them about the sizing as well if I go talk to them.