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I like the radiator. But the rug really ties the room together.

First of all, let me say, I admire your tenacity creativity and exploring the arcane world of steam boilers. 💨

In my world the OEM requirements for configuration are gospel unless signed off by a the OEM FAI. I understand that low pressure residential steam boilers can operate under non-optimal configurations but I agree with @EBEBRATT-Ed and @109A_5 that excluding elements of the recommended OEM configuration exposes contractor to risk and liability.

@EdTheHeaterMan 's comments up there on "dry" and "wet" steam are absolutely correct, and thank you for going down that rabbit hole. I've caused enough trouble with comments on naming returns that I didn't want to…

Saturated steam — which is all we ever work with in residential use — has some fascinating properties, but being an ideal gas or even close isn't one of them. This can cause all kinds of merriment when people try to treat it as such…

Technically, dry steam equals superheated steam—that is, steam with no water content at all. (but maybe not)

To make the point more clear, I go back to the definition of a BTU. One BTU is the amount of energy necessary to raise one pound of water by one degree Fahrenheit. We know that when water reaches 212°F, it will turn into a gas at sea-level atmospheric pressure.

To turn an entire pound of water from 212°F liquid to 212°F gas, it requires 970 BTU of energy. So when you add one more BTU of energy to that pound of water, the steam becomes superheated gas. That would be dry steam.

If you have a container (a boiler and radiator connected with pipes is effectively a container) and there is any amount of liquid water present, then you do not have superheated steam. By definition, you have wet steam.

If this were any other substance (like a refrigerant), we would say the system is saturated. The liquid is at the boiling point and the vapor is at the condensing point at the same time within that container.

To follow up on (but maybe not) We treat steam a little differently from other elements and compounds for some reason.

Dry steam is actually saturated steam with little or no liquid water carried with it. That is what we are trying to achieve in a steam heating system. We do not want to make superheated steam that stays superheated. We want to make steam that is as close to 100% vapor as possible as it leaves the boiler, and then have that steam condense back to water when it reaches the radiator so we can reap the benefits of all that heat energy in the rooms of our buildings.

At that point we want the steam to condense and give off all that heat into the rooms. The goal is for the piping system to deliver that saturated steam from the boiler to the radiators with as little energy loss as possible.

So, to be more clear about “dry steam,” we are really looking for what Paul is calling “wet steam” with as little “wet” in it as possible.

We still use the terms wet steam and dry steam the way they were used historically, back when the science was not widely understood. The average steam fitter knew that you needed a clean water surface, clean water, and large boiling surfaces to get the job done.

The detailed science of steam only became necessary when a problem appeared and someone needed to analyze it more deeply. So we use the term dry steam when we actually mean saturated steam that is almost completely a gas, even though we have found the science that defines our antiquated terms to be incorrect.

We still use many terms incorrectly, like sunrise and sunset, when we now know that the sun is not doing any moving at all to create that phenomenon. And a Shooting Star is not really a star at all, but we still use that term.

@ethicalpaul My compliments on another nice video.

Dry steam for definition purposes may equal the least amount of water vapor where wet steam would have the most before it changes state back to water. When steam and condensate travel in the same pipe it is a counterflow system changing state as the temperature changes in that pipe.

When I see a video like this I tend to think that I have customers, manufacturers, and inspectors and payroll to satisfy when changing and piping a steam boiler. I have to get it right. These videos give me some grace in thinking that I might have some leeway in the process. However, to satisfy the above I am bound by rules that work in the customers favor and there for my own. Again liked the video, heck, all of your videos.

Confusion reigns! (What else is new?). No, I don't think you are saying installation instructions should be ignored, @ethicalpaul . At least I don't read it that way. I think that what you are doing is exploring some fascinating corners of steam heat — which, as I have said before but without the hand-on fiddling yuo are doing, is incredibly forgiving.

I think it's clear enough that if you are installing a new boiler, you'd , be slightly nuts not to follow the manufacturer's recommendations — as an absolute minimum (you'd be amused at the overkill we did when installing Cedric).

Where it gets difficult is, as the folks above have said, is where you are dealing with an existing installation which is having problems. This becomes a judgement .call, and has to be based on a combination of experience and overall cost, as much as anything. Sometimes the best approach is to rip the whole thing out and start all over. Each situation will be a new challenge.

If you are trying to raise your main, can you get a clevis hanger on it? Use a beam hanger if running with the joists in the basement, or a 2×4 between joists with a hole drilled in. Then you can run a nut with a fender washer on top of the 2×4. Lock the clevis with a double nut. Run threaded rod up through second support (beam hanger or 2×4), then wrench threaded rod up 3/4". Everytime you raise it 1/4" run around and see the heights of rads. Sorry that description was a bit convoluted. Its easier with the 2×4, with the beam hanger you need to do a lot of double nut and washer so rod will spin.

I have a small system with a very short main. The maim is about 10-12ft long, it circled the chimney and that gives me long leadouts ro the radiators (10-12ft) so there is room for "flex". I have never felt the need to disconnect a radiator. The lever and fulcrum give a good feel for what you are doing.

Bob