Oh, My.... Unique Vapor/Vacuum System

New England SteamWorks

Yes.

SWEI

That's a real head-scratcher.

Here's a SWAG: Assuming the rest of the surrounding pipes were insulated, the (uninsulated) perforated outer pipe would facilitate a controlled heat loss in the inner pipe.

tim smith

On the steam to air heat exchangers, cut off the intakes near heat x and create a C configured duct over to other side of room it's heatin. Crate a circular flow of air. We see quite a few done this way in old manses we work on. This would reduce heat expense quite a bit.

tim smith

Btw, really like the niagara rads, never seen them out west here.

New England SteamWorks

Got to play around with this system again today. I have a feeling this might be a very long thread before all is said and done...

First, thank you to @tim smith . I brought along with me our warm air/ducting subcontractor to price out doing exactly that.

The last record of the boiler having run was 2013. An inspection of the firebox revealed 10 years worth of ashes and a disintegrated chamber. Too difficult at this stage to properly determine a replacement boiler size, so my instinct is to get the old V7 running again and work on the rest of the system. The insulation is shot where present, but mostly it's gone, the oil tank is ancient and leaking, there is certain to be trap work, vent work, and the (perhaps) ducting project . Plus the other unknowns that are unknown. Weather very warm here still, so no kind of real test today.

Here we have Master Pipefitter Nelson multi-tasking with the chamber with an assist from Master Technician Ed:





A funny story: Many, many years ago Nelson put his first chamber in in a dark basement. After applying the spray adhesive and laying the Kaowool down he checked his work with a lighter.

He's been bald and without eyebrows every since....

Anyway, the boiler fired, and we actually got her to 85.7% efficiency.

New England SteamWorks

But, we almost didn't get that far. The contractor for National Grid came around and pronounced that what was needed was a total replacement (gas of course). He recommended two steam boilers in tandem (I hesitate to use the word modulating). He didn't have as much trouble as I did with the sizing. He checked the plate on the V7 and saw it had 695 sq ft EDR, so he bid two Burnham IN5s for a total of 716 EDR. Easy! Never mind that the connected load is 1600+. He also said, when asked if he had ever worked with, or seen such a system, "Yes, all the time" and he was kind enough to send along a photo of his last installation with his proposal:




Having seen this I sent along the link to Dan's article on modular steam boilers to the owner, who promptly forwarded it to the Grid contractor for comment.

At this point it was touch and go, but the Grid contractor responded that the article was absolutely correct and that Dan Holohan is the greatest authority on steam, and he had read all Dan's books. But, that article didn't apply to his bid because Dan's article referred to piping boilers for two-pipe steam. And he thought the owner had one-pipe steam and so his piping would work just fine, thank you. I kid you not.

So the owner and I together counted the pipes on each of his 22 radiators. There were 44 in all.

And that, of course, was the end of him.

New England SteamWorks

A question for @steamhead and other gurus:

I have this counterflow job coming up which gave me an idea for this job. The counterflow job has a big loop going around the basement and ending at the highest point at the opposite end of the basement from the boiler. Thus, no place for a vent at the ends. So I plan to cut into the loop and put some 90's on the ends and some vent antlers, making two branches as commonly found, rather than one loop.

In the current system, though two pipe, the supply once again is a single loop around the basement. The return is also a loop around the basement. There are no wet returns, and no crossovers beyond the two loop seals at the boiler. There are a few Ventrite 35s on the returns for venting, that's it. It's a big long 3" main except for a narrow middle section of 2". Why not cut into the middle, making left and right branches, and put 90's on the end with vent antlers? Seems to me this would vent a lot faster than going through all the radiators and the returns before getting to a vent back at the boiler. Plus the steam collides above the boiler in a bullhead tee, and then it collides when both halves reach the middle of the loop.

Good idea, or am I missing something?

New England SteamWorks

Then we have the aforementioned loop seals:



I am thinking perhaps these work like a differential loop? The condensate in the loop keeps the steam out of the returns. But should the pressure rise to the point of potentially preventing the condensate from sliding back into the boiler, the pressure blows through the loop seal and dumps steam in the return, which equalizes the pressure and the water slides into the boiler. Or?

New England SteamWorks

I am now pretty much convinced that these are for condensing the steam prior to heading into the flue:





I climbed up on a ladder and turned the valve handle and nothing interesting happened. Just appears to be a normal open/close valve. So why the holes and how does it work? The inner tube is brass or bronze.

With all the traps working there shouldn't be any steam to condense. But, they are connected in the general vicinity of the loop seals, so perhaps their purpose is to condense the steam if the loop seals are called into action?

SWEI

That sounds plausible, especially with the high conductivity of that inner pipe.

New England SteamWorks

While I am waiting for everyone to help me with my dilemmas:

I realize astute readers are worried about the leaking oil tanks. Not to fear (gas-heads avert your eyes)(especially that Grid guy):






We also dragged a 330 in today. All good.

Steamhead

RI_SteamWorks said:

A question for @steamhead and other gurus:

I have this counterflow job coming up which gave me an idea for this job. The counterflow job has a big loop going around the basement and ending at the highest point at the opposite end of the basement from the boiler. Thus, no place for a vent at the ends. So I plan to cut into the loop and put some 90's on the ends and some vent antlers, making two branches as commonly found, rather than one loop.

In the current system, though two pipe, the supply once again is a single loop around the basement. The return is also a loop around the basement. There are no wet returns, and no crossovers beyond the two loop seals at the boiler. There are a few Ventrite 35s on the returns for venting, that's it. It's a big long 3" main except for a narrow middle section of 2". Why not cut into the middle, making left and right branches, and put 90's on the end with vent antlers? Seems to me this would vent a lot faster than going through all the radiators and the returns before getting to a vent back at the boiler. Plus the steam collides above the boiler in a bullhead tee, and then it collides when both halves reach the middle of the loop.

Good idea, or am I missing something?

Let me make sure I have this straight: The boiler feeds into 3" counterflow mains which loop around the basement and end in that 2" section connecting them together?

New England SteamWorks

No, sorry @steamhead if I wasn't clear. Two separate jobs. One is a counterflow (which I will do in the future and not relevant here) which gave me the idea for the current job discussed in this thread.

The current job is two-pipe, but (correct) the 3" main loops around the basement and connects together in the middle with a 2" section. It is a continuous loop.

Ironman

Maybe it's a redundant flux capacitor!

Steamhead

RI_SteamWorks said:

No, sorry @steamhead if I wasn't clear. Two separate jobs. One is a counterflow (which I will do in the future and not relevant here) which gave me the idea for the current job discussed in this thread.

The current job is two-pipe, but (correct) the 3" main loops around the basement and connect together in the middle with a 2" section. It is a continuous loop.

And the drip connection is in the 2" section?

New England SteamWorks

No. @steamhead there are no connections at all between the supply and returns (except through the radiators of course) beyond the loop seals, which are right at the boiler with the 3" supply.

Steamhead

OK, I got it now- guess I'm getting old. These mains are basically counterflow, with the loop seals near the boiler draining any condensate that might be in them.

If there are no rads connected to that 2" section, I would agree- take it out and put vents there.

Regarding the loop seals- it won't take much pressure to blow them out. Use a Vaporstat, and if that doesn't work, remove them and drop the drip lines to floor level and connect them to the Hartford Loop.

New England SteamWorks

Hmmm. I'll check again when I go next, but I didn't notice any pitch on the supply main. Thanks, as always.