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Hot Water to Steam Conversion

I am going out to look at a possible Hot Water to Steam conversion.  It sounds like a typical old gravity hot water system in a 2 flat.  The owner is aware that it will be more expensive than just putting in another hot water boiler, but still wants steam.  I suspect I just need to plumb the beginning of the old hot water supply mains with a drip, since they would be pitched back towards the boiler, orifice plate the supply valves according to room load, and use the old return as my condensate return.  Probably a lot of system cleaning will be involved as all that old sludge gets steam cleaned out of the system.   Anything else I should be looking for?

With Chicago going more and more green, I am seeing requests for Forced Air to steam conversions too.  Probably will be putting in some of the copper minitube steam systems that Gerry Gill has done or my own variation of them.  Already have the historic engineering data on the design.   When I show people that I have a 10,000 sq ft poorly insulated 1930's mansion heating with steam vapor and gas bills only hit $500.00 midwinter, they are taking notice.  (so does the gas company...they send someone out every year to "check" on the meter)

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  • heatpro02920
    heatpro02920 Member Posts: 991
    edited May 2013
    Wow 10sq ft pooryl insulated 30's era house that uses

    $500 in the Chicago's coldest months!!! I am finding that hard to believe, I hate to play devils advocate here BUT...

    2 reasons I just have to...

    I have a customer here in Rhode Island with an 9700 sq ft house, natural gas, buderus GB142's, buderus radiant panels, zoned so not to heat unused areas {because lets face it who uses all of a 10K sq ft house}, with ODR, delta t circs, the whole 9 yards, built in 2006 {I did the entire mechanical system, with solar DHW, and Heat pumps taking care of the heat when outdoor ambient is over 50*'s and their winter gas bills are more than $500. He is a very good friend of mine and going from his old 6K sq ft home that used multiple 80+ FWA systems and pying over $1200 a month he was very happy with the results...

    Next is a house on the east side {some may know it, on the corner of lloyd near Brown U, is a customer of mine, with a well tuned WM commercial steam boiler, a little over 10K sq ft built around that same era {but well maintained and insulated here and there} and his mid winter energy bills are north of $1800!!!! I know I can get that under $1000 with a hydro air system but he will not hear it, he said if I ever think the steam boiler for his house is going to be hard to get, to tell him and he will buy a spare!! But the radiators are a very iportant part of his building to him obviously, although his wife hates them, and they have small kids, so the rads, are all surrounded by baby fences, lol...

    Next reason- One of my own personal properties, only has 1 gas meter, 2- 1100ish sq ft apartments, with new windows doors and some new insulation {my rule is if I take the wall out I put it back with insulation}, 7ft ceilings thoughout, 1 thermostat, burnham mega steam with an ez gas {causes fewer issues than you would think, I had good tenants there} costs me around $400-$450 in winter months....

    So when you say 10K sq ft, poor insualtion, chicago winters, $500 a sq, I would love to see some pics of the design and heating bills, because I could save customers around here a lot of money.... Unless they have the t-stat set to 50 and almost all of the radiators shut down, I am having a hard time wrapping my head around it... that is .05 per sq ft to heat the building, my own home which is BRAND NEW, less than half the size, insualted to the moon with a tt 175, heatpumps working down to 47, and useing coal for cold weekends costs me almost double that 9cents per sq ft in the coldest months....

    I am sorry but, I dont see it, because no matter what, your building has a heat loss, and no matter what that boiler has to produce AT LEAST that amount of BTU's, and the building you describe would have a heat loss around 500K..... My program is calling chicago a -12 design day temp, where here I use between 0-5 degree design day temps... so its colder there...

    So I dont know if you put plutonium in that heat exchanger or are some kind of magician, but if you are doing what you say you are, you should be writing books with DAN....

    As for swapping people to NEW STEAM, I would like to borrow some picture of jobs in progress and before and afters, to show my customers {you can put your comapany name on them, just for visual aid, because this morning when I was a t RE, since we have been discussing steam I thought to grab some literrature on "new Steam" guess what, he looked at me like I had 9 heads, but came up with a company that sells new steam rads, they are good looking , just tube ladder style, I doubt they will last like the old ones did, but still nice units, unitl I seen the price, Good lord, you can buy a small mod con for every room for what they want for them things, LOL....
  • Rod
    Rod Posts: 2,067
    Gerry Gill's Marvelous Mini Tube Steam System

    If I was putting in a new complete steam system I would definitely consider Gerry Gill’s amazing Mini -tube system.  Here are the links for any one who hasn’t already read up on it.  




    As for radiators - I think a lot could be done with a fan boost fin tube similar in concept to the original Select Temp radiator.  Adding a fan boost really ups the BTU output and speeds the heat distribution, especially in a set back situation.  Jaga radiators have a similar boost system (DBE) available for some models of their HW radiators.  I haven’t checked it out while they are approved for steam there may be a possibly some of their models could be adapted for steam.  You sure can’t beat them for styling!

    Here’s some video on D.B.E. : http://www.youtube.com/watch?v=mm1t5E0LB4g   


    Jaga catalogue: http://catalogue.theradiatorfactory.com/#home

    Check the output tables for the DBE, The boost fan almost doubles the BTU output.

    - Rod

  • Here's the heating plant

    2 Slantfin TR-40s firing about 200,000 input each, stage fired with a two stage thermostat.  All radiators are now orificed...system originally an early Warren Webster system (pre orificed supply valves).  I am sure are gas is cheaper here, but the truth is the truth.  Also, the system only runs one 1/6 hp motor on a single burner for most of the winter.... a fraction of the power needed to run hot air fans and even pumps let alone power the electronics and draft fans of "High Efficiency" furnaces or boiler.  1/6 hp is more than necessary to fire the boilers.

    The new burners I expect to start using have ECM motors so the power draw for this same home would be about 1/2 again or less than it is now.  I suspect power draw will drop down to about 40 watts with this boiler design.

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  • Gerry just used Findtube

    Very small fintube, since the output is about 60% higher with steam than high temp hot water.

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  • Steamhead
    Steamhead Member Posts: 15,881
    Definitely want to drip those mains near the boiler

    even it it's two-pipe.... for example, many Broomell systems have counterflow mains and if you don't pipe the boiler just right, condensate will build up in the mains and block the steam flow or cause banging.

    We ran into this a couple years ago, where a mis-piped boiler caused this very problem on a counterflow Broomell. Gordo and I built a proper header which cured the problem.

    We've seen several old gravity hot-water systems in Baltimore that were converted to Vapor back in the day. My guess is they never circulated well on hot-water. I'll never forget the first time I saw one, long before we started our company, had to look at it a few times before I figured out what it was. We still service that system, and it's still Vapor.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • gerry gill
    gerry gill Member Posts: 3,054
    Actually, my system has

    three lengths of steam fed fin tube,

    one steam fed copper convector cabinet,

    one steam fed beacon morris fan unit,

    two lengths of water fed fin tube with the water heated via a steam heat exchanger, and

    my latest addition- i wanted to add a radiator to the kitchen, so i installed a cast iron radiator that i took out of a house during a kitchen remodel, that was originally one pipe steam. I removed the original inlet valve, and inserted a bushing, and a radiator trap. I could have removed the top opposite bushing for an inlet valve, but decided to see what would happen if i tapped the old air vent hole to 1/4'' and fed the steam there. It works great! I'm now thinking of doing this when people have room additions on steam heated houses. Why not give them what they already have? I could put in cast iron radiators but feed them via mini tube. Or revamp an existing one pipe system and feed back thru the air vent tappings. I bet a needle valve would work on the inlet to act as an orifice whereby the original inlet valve could stay as the return connection.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • Steamhead
    Steamhead Member Posts: 15,881

    and how little pressure does it take?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • gerry gill
    gerry gill Member Posts: 3,054
    I'm set up

    the same as a one pipe system usually is with a cut out at a pound and a half.
    Serving Cleveland's eastern suburbs from Cleveland Heights down to Cuyahoga Falls.

  • ttekushan_3
    ttekushan_3 Member Posts: 950

    We had discussed that option a couple years ago in terms of converting or "downsizing" big single pipe systems!

    And you would be just the person to try it since, well, it's not like we're loaded with new mini tube systems.

    That's wonderful how well it works.
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