1 Pipe Steam to 1 Pipe Hot Water?

BenK

Hello everyone!

I’m going to apologize in advance for the length of this post, but I fell it’s important to include too much history and information rather than not enough. When I originally tried posting this, it told me it was too long, so I have to break it into two posts, this in the 1st part and the 2nd part will be the 1st reply.

I’m very new to this site; I actually stumbled across it by accident through Google searches about steam heat and seeing a couple of Dan’s videos on YouTube. The company I work for, we do repairs and work on existing steam heating systems, but 90%+ of the heating work we do in new construction is hot water, for obvious reasons. We don’t mess with ductwork; we leave that for the tinners. Even though I’m only 33 years old, I know quite a bit about hot water heat since I have been working in the plumbing field “officially” since I was 14 years old (I actually knew how to operate a backhoe before I knew how to ride a bike because when I was a kid my parents couldn’t afford daycare so I rode in the backhoe with my dad while he worked, and since then I was hooked on heavy machinery & plumbing).

As I said, we primarily install hot water heat, but we do service steam boilers and steam systems. Perhaps it’s the history buff side of me shining through, but I have always been fascinated by steam, whether its steam engine trains or whatever. But I’m a plumber, so why not be fascinated by steam heat, right?

I realize a vast majority of this group is from the New England states where steam was and is still a primary way of heating, and I live in the upper rural Midwest. Surprise, we have heat here too, and cars, and internet haha. Joking aside, there are still a lot of old houses and buildings here that are still heated by steam. Although, most modern homes are heated by scorched air and some upscale homes go for hot water infloor heat, however the vast majority of our hot water heat (and chilled) is in commercial buildings where we pump hot water (and/or chilled) to VAV’s.

There are a few people at work that know a lot about steam heat, but they’re all older, and one of them that was a genius on it retired last year at the young age of ~70 years old, so my options of people to ask about it are becoming more and more limited as the steam experts retire and us younger hot water guys are left not knowing any of the knowledge they have. I always kick myself for not asking more questions about steam heat while the opportunity still exists, but you don't really think of it when you're almost always working with hot water. The only time you really think about steam is when you have to do work on an old system.

Sorry for the not so short & sweet back story haha. Let's move onto some history of the property I'm curious about. My boss owns an apartment complex that was built in the late 1890’s or early 1900’s, probably shortly after your Dakota building was built; the only difference is this complex is actually in one of the Dakotas. When it was originally built it was luxury at the time, but as decades went on it fell into disrepair and had hobos sleeping in the hallways and turned into a real craphole (it’s only a block away from the old train depot, hence why hobos slept in the hallways). Once my boss bought it, he fixed it back up. It’s not luxury by today’s standards, but they're good apartments. The original complex layout (see attached picture for an overhead visual) is a 3 story main building, plus basement, in the middle and located behind the main building, and connected via an underground link in the basement, is an old garage/storage/coal unloading area on the ground level (the old train tracks that backed up to the garage door to unload coal are still buried in the parking lot; that's pretty cool), and the physical plant in the basement where two old brick coal boilers still sit, but were abandoned long before any of us were alive, and the complex now runs on natural gas. Along with the main building and the physical plant was an old dilapidated building that was torn down, and is now a parking lot behind two of the existing buildings. From an overhead view, to the right of the main building is an old 3 story, plus basement, Victorian home that was converted into apartments, and on the left side of the main building is a 3 story, plus basement, building that was once the original building for one of the schools here in town, but was also converted into apartments. I'm not sure when the apartment conversions took place, but the building in back was town down by my boss because it was in complete disrepair, it didn't even have a foundation left from decades of neglect. I remember walking through that building when he bought the place, it was nasty; hobos sleeping, peeing & pooping in the hallway, tenants would just throw their garbage in the hallway or out their windows onto the ground outside, just a filthy & ruined building. The other buildings were fixable, but that one was too far gone.

BenK

Here is the 2nd part:

So that's the layout of the complex, now on to how the steam was/is piped. From my understanding, the original steam piping was split into several directions for the different buildings, controlled by a control valve(s) in the physical plant. In one direction it ran underground from the physical plant to the dilapidated building, and then ran to the Victorian mansion from the dilapidated building. In the other direction the steam fed the old schooling building through a tunnel in between the buildings (by accident we found a small manhole access to the tunnel buried in the yard), and then fed the main building by running through the basement link. This might be what you guys in the New England states, especially New York City, call a co-gen system. I don't know for a fact that's how it worked at the time, I'm only speculating. The dilapidated building was torn down, and the steam line fed from that building to the Victorian mansion apartment building was somehow routed to just feed the Victorian mansion apartment building. Since then, we converted the Victorian mansion apartment building to hot water baseboard heat with its own hot water boiler and an indirect fired water heater in the basement (basement is basically an unfinished storage area), and the steam line that went from the main building to the Victorian mansion apt building was cut off at both ends and abandoned, but nobody ever capped the abandoned line at either end like we were told to...oops. Sorry, another side story. My boss is a pretty smart guy, and wanted us to put the hot water boiler on a tall stand just in case, so we made a 2' tall stand to set the boiler on. It's a good thing he had us do that because the storm sewer on the street corner that building sits on is prone to flooding during heavy rains, and during one heavy rain the water was knee high between the Victorian mansion and the main building; the water weight got so heavy against the basement windows of the Victorian apt building that it broke one window and started flooding the basement. Remember how I told you that we forgot to cap that abandoned steam line running from the Victorian building to the physical plant? Yep, you guessed it, all that water from the basement of the Victorian building was now flowing to the physical plant basement via the abandoned steam line that we forgot to cap. Yikes, we could've got into big trouble for that, but luckily enough that abandoned steam line kept the water level under that 2' stand he had us put the boiler on, and the water ran to the physical plant where the sump pump pumped it out; the Victorian building didn't have drain tile or a sump pump, just a single floor drain. Talk about dumb luck since the water didn't reach the hot water boiler and ruin it. I guess by forgetting to cap the abandoned steam line we accidently draintiled the Victorian building haha.

Sorry, I like to throw in the history of a place when I know about it; I think it helps add character to the property and a bit of personal feeling to it. I'm not sure what type of steam system the old school building uses (1 pipe, 2 pipe, which way it slopes, how the condensate runs, etc). The limited bit I do know about steam tells me that the main building is a 1 pipe system, and from the best of my memory the main steam line is sloping up & away from the boiler, which tells me it's not just a 1 pipe steam system, but it's also a 1 pipe counter-flow steam system (correct me if I'm wrong). There is a condensate drain that runs along the floor in parts of the basement of the main building and into a condensate tank in the physical plant (I suspect the condensate tank was used because originally it'd be tough to try and maintain temp in 4 different buildings using 1 thermostat, so they needed the zone valve(s) & the condensate tank). Now 2 buildings have been eliminated from the steam system, one to its own hot water boiler, and one that was demolished, which leaves 2 buildings remaining on steam.

To finally get to the question: I read in PM Magazine one time how they were able to convert an old 1 pipe steam system in a house to hot water heat without replacing any piping and I cannot find the article anywhere, they just changed the boiler, and very little, if any, piping in the mechanical room, they had problems but realized it was with the pump so they swapped it out for something that was a more slow moving pump that mimicked gravity heat. The big question: Is it possible to convert a one pipe steam heat system to a one pipe hot water heat system without changing piping or radiators? The main building is 3 stories, plus basement, with 2 apts on each floor. However the basement apartments have been gutted and nobody lives down there, but the abandoned apts do have ceiling hung registers. The old school building is 3 stories, plus basement, and I think that building has either 2 or 4 apts per floor, and the basement has apartments in it.

I'm terribly sorry for the extremely long lead up to my question, but I just wanted to lay the groundwork and history for the situation I was describing, well, because history is interesting.

Jamie Hall

Honestly, I can't see how it could be made to work... maybe someone else can. But I do have a question: why do you want to change? One pipe steam heat works splendidly well, provided you take a little trouble to get it set up properly...

BenK

@Jamie Hall Way more efficient to heat with hot water, cheaper heating bills. Plus each apartment can be on their own zone. If he ever did convert it to hot water we'd probably remove the entire steam system: radiators, piping, boilers, everything and put a bank of IBC hot water boilers in the physical plant and run copper to baseboard in each apt. We'd probably replace the water heater with an indirect fired water heater too.

It's just more out of curiosity than anything.

Steamhead

Well, if you're in the Dakotas and ever lost power or the gas supply was interrupted in the winter, you'd be up a creek with a hot-water system since it would freeze up. Steam won't do that to anywhere near the same extent because most of the piping drains dry when the system shuts off. There's only water in the boiler, condensate tank and some pipes in the basement at that point.

@Jamie Hall knows about getting a steam system set up properly and how well it can run - he manages a historic property with steam heat. It really isn't rocket science, though someone pushing hot-water or scorched-air conversions would probably try to make people believe it was. When properly set up, steam will equal the comfort and approach the efficiency of hot-water. If your plan was to "remove the entire steam system: radiators, piping, boilers, everything and put a bank of IBC hot water boilers in the physical plant and run copper to baseboard in each apt", you'd never recoup your investment. And those mod-con "boilers" have not stood the test of time the way steam has.

Oh, and parts can be hard to get too, and none of them are standardized like those on a steam system are. Not long ago, we actually had to wait two weeks for a Crown mod-con sensor that no one had in stock. We won't put our customers through that, therefore we don't recommend these things.

If a steam system is using a lot of fuel, something is wrong with it. The problem is not "just that it's steam". We've been able to cut some of our steam customers' fuel consumption by a third, for much less cost than converting (which was recommended by others), thus disproving the steam-is-inherently-inefficient myth.

Now, as to your original question: I remember a discussion like that. The original system was not steam- it was an old gravity one-pipe hot-water system. These were piped something like Monoflo systems and some of them used special tees to distribute the water to the radiators. On this type of system, an oversized circ will make the water stay in the main and not circulate to the radiators. Slowing down the flow rate with a smaller circ mimicked the original gravity flow rate, and the system worked properly.

Jamie Hall

No, it's not "way more efficient to heat with hot water". Scrap that idea; it's just plain false. At most -- at the very most, assuming everything is installed just so and you have enough radiation to allow running the latest mod/con hot water boilers at their maximum efficiency you might gain around 8% in efficiency. Anyone who tells you anything else simply doesn't know what they are talking about. Sorry.

Jamie Hall

Ah yes, @Steamhead -- I seem to remember that discussion on a gravity flow hot water system, too. That was years ago!

BenK

I'm not sure why, but my comment was posted, then removed, and if I try to post it again it says that it has to be approved first.

Fred

BenK said:

I'm not sure why, but my comment was posted, then removed, and if I try to post it again it says that it has to be approved first.

Probably because of the length of the original post that turned into 2 posts.

BenK

Fred said:

Probably because of the length of the original post that turned into 2 posts.

There was a lengthy reply on this thread by someone else that wasn't removed. At first I just thought something funky was going on with my browser, but that doesn't seem to be the case.

Fred

BenK said:

Fred said:

Probably because of the length of the original post that turned into 2 posts.

There was a lengthy reply on this thread by someone else that wasn't removed. At first I just thought something funky was going on with my browser, but that doesn't seem to be the case.

There is a lengthy post by someone else but not as lengthy as your original two. I don't know if the fact you started out with one really long post that could not be posted and then broke it down into two has anything to do with it or not but you are able to post now. Try posting your response again. Hopefully it was saved as a "Draft" and you can just copy it and paste it .

BenK

@Steamhead @Jamie Hall Actually with the one apt building we converted to hot water, I believe they said they recouped the cost of the labor & material within a few years by the money they saved on the utility bills; basically changing it paid for itself pretty quick. Keep in mind, our labor cost here in the Midwest is probably not nearly as high as it is in the New England states. You have to keep in mind different regions of the country are not all the same as your region of the country. It probably doesn't hurt that since we're plumbers and it was the boss's apt building that he probably didn't charge himself a markup on labor & material.

I never said steam wasn't efficient; it's just not as efficient as hot water. It's hard to argue that a 60% efficient boiler is just as efficient as a 95% efficient boiler.

We worked on a project where a theater had us change their steam system to hot water (To my knowledge there wasn't anything wrong with their steam system, the company I work for serviced it for years. But the theater was a nonprofit, so they had to spend their money & this was what they decided to spend it on; that's their choice). The heating system consisted of the theater/auditorium, a bar on one side, a store on the other side, and apartments on the floors above. The first winter after we changed it to hot water they said they had something like a 30% or 40% savings on their heating bill. Maybe it was a more mild winter that year, I don't remember. Unfortunately, they never got to see a return on their investment because a couple years after the install the building caught on fire and burnt down from a kitchen fire in one of the apartments; thankfully there wasn't a play taking place at the time, and no one was hurt.

A power loss or gas interruption is something that will negatively affect any heating system, steam or hot water. Even if the only pipes that freeze and break on a steam system are the condensate and the boiler itself (which is still not good). If the building freezes, the domestic water lines are probably toast. I guess with a hot water system you have the option to put glycol in it so it doesn't freeze, but again, if the building freezes the domestic water lines are likely gone. Moral of the story: There will likely be major problems with something else in the building other than the heating system if a building freezes.

Something doesn't have to be around for a 100 years to be considered reliable. The same argument could be made for "Why are you using a natural gas steam boiler instead of a coal one? Coal has been around a lot longer than natural gas." We are currently using the internet instead of snail mail and it's much more efficient and reliable than mailing letters back & forth to each other via the Postal Service even thought the Postal Service has been around well over 100 years longer than the internet. Do you use a cell phone or a telegraph? Do you drive an automobile or ride a horse drawn carriage? Is one newer than the other? Yes. Has the newer one been around for a hundred years to prove that it's reliable? No. Is the newer one still reliable? Yes. Is one a little more efficient than the other? Yes. But do they both work? Absolutely. This wasn't intended to be a hot water vs steam debate. I never said steam wasn't, isn't, or couldn't be efficient. There's no need to act like someone just peed in your Cheerios.

The question, which was out of pure curiosity, was about if it was possible to convert from a 1 pipe steam system to a hot water system using all the same piping and radiators because years ago I thought that was what I read in a PM Magazine. As you said, "[In the article] The original system was not steam- it was an old gravity one-pipe hot-water system." That answered my question. I'm not sure why, but for some reason I thought the article said it was steam. I'm glad someone else read that article and remembered it. Thank you!

Jamie Hall

OK. Two things. First, a modern steam boiler, such as Cedric -- see my signature -- is 86% efficient (by actual measurement), not 60%. You're comparing a 1955 Ford to a 2018 Ford, and that just isn't fair -- nor honest.

Second, so far as I know no, you cannot convert one pipe steam to hot water.

But -- it's your call. I'd stay with the steam and save my money.

Steamhead

Apparently your posts aren't the only ones getting truncated. @Erin Holohan Haskell ?

In my complete original post is the line "If a steam system is burning a lot of fuel, something is wrong with it". Tearing it out is like getting a new car because the ashtrays got dirty.

Look at my company's Find a Contractor ad. On that job the gas bills were way too high, and we cut their consumption by a third. This was not good news to several other contractors who wanted to tear the whole thing out. The savings amounted to roughly $10,000 per year, in 2005 dollars.

There is someone else who occasionally touts replacing steam systems, but he has not been able to show better savings than our company has as a result of fixing the steam.

BenK

Jamie Hall said:

OK. Two things. First, a modern steam boiler, such as Cedric -- see my signature -- is 86% efficient (by actual measurement), not 60%. You're comparing a 1955 Ford to a 2018 Ford, and that just isn't fair -- nor honest.

Second, so far as I know no, you cannot convert one pipe steam to hot water.

But -- it's your call. I'd stay with the steam and save my money.

First, Not my building, and not my money lol. Also, we're so busy with work that I don't see him deciding to change the building over anyways, maybe if we had a slow summer or something. That might have been the reason we did the change over of the one building 10+ years ago; it might have been a slow summer that year, so he found work for us to do, and it saved him some money in the long run. The whole thing was just a question out of pure curiosity to begin with.

Second, I'm well aware that new steam boilers are much more efficient than old ones. Like with most things, over time they get better and become more advanced as new technology develops and evolves. However, the boilers that are in there now are far from new; they are old enough where they are in that 60% efficacy range, which is why I made that comparison; they are 1955 Ford's lol.

BenK

Steamhead said:

In my complete original post is the line "If a steam system is burning a lot of fuel, something is wrong with it". Tearing it out is like getting a new car because the ashtrays got dirty.

They are pretty old boilers; they're not new by any means. They're not a 2018 truck with a dirty ashtray; they're more like a 1955 with five hundred thousand miles on them. They've just been maintained pretty good throughout the years, and I think they get serviced annually every fall.

mikeg2015

First, maybe I missed it, but unless you have air vents on the radiators, it’s a 2 pipe system. I’d be supposed to see a 1 pipe on multiple buildings. You’d have condensate return problems. Through it could have wet gravity returns I suppose and still be 1 pipe. Sort of defeats the simplicity.

mikeg2015

To convert to hot water with a single pipe, you’d either have to 1” add a return line or 2, use a gravity system.

Steam in not ineffceint. My calculated use matches my estimated heat loss given the size, construction and air leakage rate. I could have easily add a 96% furnace when I added central air. Steam is just so nice.

BenK

mikeg2015 said:

First, maybe I missed it, but unless you have air vents on the radiators, it’s a 2 pipe system. I’d be supposed to see a 1 pipe on multiple buildings. You’d have condensate return problems. Through it could have wet gravity returns I suppose and still be 1 pipe. Sort of defeats the simplicity.

It does have air vents on the radiators, and just one steam valve going into the radiator. Isn't that a tell tale sign of a 1 pipe system? I'm not sure how the condensates run, but I do know there is a condensate tank.

BenK

mikeg2015 said:

Steam in not ineffceint. My calculated use matches my estimated heat loss given the size, construction and air leakage rate. I could have easily add a 96% furnace when I added central air. Steam is just so nice.

I didn't say it was inefficient, I just said it's not as efficient as hot water. My house has a furnace, it's just what it's always had. At least the last owners updated it to a really good one, but I prefer infloor heat. If I would've won that $1B Mega Millions my dream house would have infloor heat, and every room would be it's own zone. The only downside is that'd be a lot of thermostats to look at lol

Steamhead

@BenK , maybe you should arrange for one of us to come and consult. Which Dakota are you in, and what part?

Erin Holohan Haskell

BenK said:

I'm not sure why, but my comment was posted, then removed, and if I try to post it again it says that it has to be approved first.

@BenK, sorry about that. Sometimes a post will get held if the Post Comment button gets clicked a few times. It's to prevent spam and duplicate posts. I'm not sure if that was the case here, but there were a few of that same post being held. We're all set now, though.