Old Steam Restoration

Robbie

Hi- I am new to the forum, and am just getting into the steam heating repairs on an old house...



Let me give you the background, quickly:

Purchasing an 1883 Victorian(cottage) which was equipped with single pipe steam at some point. The most recent owners started removing the system(!!!) in favor of some, unknown replacement. The mains and risers are still in place, but all the radiators were gone. My intent is to refurbish the steam heat, and make it work well. (Boy, and I a dreamer, or what...lol)



I have read fully Dan Holohan's  "The Lost Art of Steam Heating", and believe I have the concepts pretty well in hand, but I have a few questions, or rather clarifications I seek...



I have checked the mains alignment, and, other than a few high spots which need to be eliminated, it is ok. The risers are interesting- all but one feed a single radiator each, and have 1 1/4" OD pipe at the radiator valve.(The mains are about 2 3/8" IIRC). The riser which feeds two radiators, on the 2nd floor, is 2", and is the last riser at this point.(a further riser, to be reconnected, is disconnected at the moment) All the first floor risers come off the mains at 45 degree. The 2nd floor risers, and one first floor one, come off at 90, after coming through a 90 into it... The system has a dry return, and a Hoffman 75 vent, which is located at the 90 down for the return to the Hartford loop, about 10" above it. The steam boiler is an older Weil McLaine EG-45, and will need replacement, most likely with the same.



My reading has led me to believe I need to do a few things: As I can't very easily change the 90s into 45s, as the pipe is old & still has its insulation(which I have no intention of removing, as the stuff is safe unless disturbed...) so I don't want to have to fiddle there. My thought is to add drip loops to the upstairs risers, so I can reduce the condensate speed into the mains. But I have no idea how to connect a wet return pipe into a dry system! If I added the condensate return, or wet pipe, parallel with, but lower than the mains, would it just connect into the water return below the water line? Also, can the wet & dry pipes work together the way I am imagining?(2nd floor & 90 deg risers feed drip loops & wet return, 45 deg. first floor risers return to mains only)



My next question is, if I add the wet return, can I put zone shut-offs on each riser, add a drip loop to wet return on the radiator side of the riser, and control the steam flow to each radiator independently, using a room mounted thermostat for control?



I will probably have more questions, but these are good for a start! I do have pics available, if they help the discussion. And I have 7 of the 10 or so radiators I need.



Thanks for any replies-

Scott

ttekushan_3

I presume the new radiators

The new radiators should be sized to the actual heat loss calculations. The older systems were oversized for a variety of reasons and right-sizing is always a challenge-unless you do what you are doing. Then size the boiler to the connected load, using the IBR ratings. Make sure the EG 45 will be the right size.



If the radiators are smaller that the originals, I doubt that the need for a new wet return would be necessary. Once breaking into the risers to introduce a relief drip, you should really do all of them. The wet return should come in low and then rise into the Hartford loop. The Main should drop into the same wet return at the Loop.



Your thought of dripping the radiator after the radiator shut off is interesting. Were you to do this, I wouldn't drip the risers at all because you would be accomplishing this with the new drips. The path of least resistance for the condensate developed by the radiator would be your new drips after the shut off valves. You could leave the old piping alone entirely. The flaw is that a large shutoff electrically operated is an expensive device. This is usually done more economically at the radiator vent to prevent the radiator from heating when the system comes on, though a fully saturated radiator will continue to heat even if the vent closes. I'd prefer the floor valve. Also bear in mind that an additional drip as you describe may allow you to go down to a 1" valve, making it more affordable a choice.



Just some thoughts.





-Terry

Robbie

More Questions...

Hi- Thanks for the reply! I am still trying to establish the "proper" sizes for the radiators: I have been going through the book(Lost Art...) and have to fin the info on room size vs radiator size. I picked up 7 radiators form a similar size house of the same period, and they are about the same physical footprint as the ones which were there, but I am not sure about their relative height. There is one original radiator in the house- it was left in the attic! But it is not connected.



To clarify about the shut-off valve idea, I meant that I was thinking about installing them where the riser comes off the mains, and dripped on the radiator side of the valve- not placing the valve up at the radiator, and the radiator also dripped- this would give me two pipe steam! My thought is that if the steam is shut off at the mains, then it will need no drip beyond minimal to prevent it from backing up against the back of the valve, and making a hammer when opened. Also, this would reduce steam going when not needed, and theoretically reducing cycling of the system... Again, speculation...



I have another question to pose, and that is regarding "Bullhead Tees" I am not sure, but it looks like I may have a couple at my boiler, as part of the Hartford Loop and Mains take off, as there are two steam outlets from the top of the unit. Check the photos below, and let me know what you think... Does the Hartford Loop look normal?



Thanks!

Scott

Robbie

Hoping...

I am hoping to get some more info on this post-



Thanks!

Scott