Best Of

Thanks @Jamie Hall and @PC7060 and others, you get me 😂

I did want to reply to one thing Jamie wrote:

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.

But I think I'm showing that there is really almost never any need to rip anything out and start over (at least until the next boiler replacement). I will assert that almost any boiler installation will make good steam as long as the water quality is good.

Look how good my steam is in this video with a direct 1-1/4" pipe directly from the boiler to the main. Heck, even that ridiculous S-curve isn't causing any fuss. This is because my water is good. If I put a tablespoon of oil in there I would have a main full of liquid water.

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 Great video, I wish I had that drive and motivation.

I think on a forum like this best practice should be to promote best practice. Will steam heating still work with near boiler piping that is not optimum, we all know it will. To me when troubleshooting any system, steam, electrical, etc. observe all the deficiencies, oddities and defects, deal with the easy, quick, inexpensive stuff first like obvious poor water quality, pipe pitch, see where it leads.

At the time of installing a new boiler best practice should be to promote best practice.

Weather it is steam or anything else one of the most difficult things for me at least is to go into a cobbled up job where they are having problems and it looks like it was piped by a bunch of monkey's. Usually looks like crap, the pipe sizes may be wrong, it may be the wrong material (copper) the wrong size boiler etc etc.

Where do you start is the difficult thing.

If you a building owner or homeowner you can piecemeal the thing and take all the time you need to try this or try that and try to make it work.

But if your a contractor you can't do that. Labor prices are too high (not to mention the material). If you go in and try and tweak it and it doesn't work then you get called back so you try something else and that doesn't fix it either.

Now the customer gets the bill and explodes because it still isn't fixed. Better to go in and fix it get in get out get paid,

No win situation sometimes.

If you fix it and they pay a big bill (yeah that sucks) but if its fixed in the long run they will say "yeah it cost a lot but its fixed"

This is the end of my 3rd year of involvement in steam heating systems. I am at a loss to explain how anyone can say that any radiator vents are good. I can name no vents that are used for radiators that are of good quality [Low out of box failure or in service failure percentage]. Of vents used for mains, I did find one of good quality that many mentioned on this and other sites. It is my understanding that for plumbing and related devices [Valves, Vents, pressure relief valves, ect] the failure rate "out of the box" is under 2%.