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Valve to convert one-pipe steam rad to hot water

I found out the other day that our steam oil boiler (modified coal)is considered dangerous due to lack of safety features. I am a middle school teacher with two little boys and my wife an I bought this house at the beginning of the summer. We plan to stay awhile.

We are scheduling quotes to switch to forced hot water and talking with the natural gas utility to find out if we can go in that direction. My big question is: do we have to get rid of the steam radiators we have (one-pipe but the sections are connected across the top) and switch to baseboard? Factors for consideration are 1. my wife grew up with baseboard and is not a big fan, 2. we live in Maine so we would like consistent heat not hot-cold fluctuations, 3. I teach middle school, glamorous but not lucrative.

The person who first alerted us to the situation mentioned a valve that can be used to convert one-pipe steam radiators to forced hot water but when I searched on the web, I only found one reference in a .pdf from "Hydronic Alternatives" about "The single entry injection valve." Has anyone had any experience with these and what do they cost?


Re: Valve to convert one-pipe steam rad to hot water

I have limited knowledge when it comes to boilers but you can take follow this link, I'm sure Nashuatech will be along at sometime with his vast experience, he is the man. Good Luck!!! :)


Re: Valve to convert one-pipe steam rad to hot water


I would support your obtaining quotes & estimates for a conversion to forced hot water heating, but I would get at least one more opinion as to the safety of your steam boiler---sometimes this ploy is used just to sell you a new boiler.

The "hydronics alternative" valve listed by Sten is one alternative, but my recollections is that there are some cautions to follow before going this route.

The labor cost may be too high, considering:

1) the tendency of steam piping to bond at the joints thru rust after years of steam service---in any event, the steam piping would have to be cut out, at least at the convector sites, and possibly throughout the system.

2) the accumulation of mineral salts & crud leached out of the steam over the years accumulates in the piping & may interfere with the new hot water system.

3) as I recall, the rads don't heat up as completely using this system.

4) there may be no installers who have experience or are willing to take the liability that the modified system will work properly.

You are doing the right thing by getting several estimates from various installers in your area as to the best way to go about this conversion---in the end, you will have to depend on one installer to come up with a reasonable solution at a reasonable price.

There are alternatives to baseboard as the heat convectors---there are the newer steel panel radiators (many originating in Europe & now Asia) by such mfgrs as Veha (relatively low cost), and several others listed in the sites below---generally speaking, steel panel rads are quite high in price, but make an excellent appearance & are becoming more popular---these convectors still have a "high-brow" aspect to them & many are overpriced.

There's nothing to prevent you from shopping local salvage yards, demolition yards or used plumbing supply yards---low-cost used hot water radiators are widely available, will last forever because they're cast iron, & may need just a new paint job at the local auto body shop---you would need just one or two good sized ones, considering the other alternatives available, as noted above---bring some help---they can weigh 300 lbs each.

Radiant floor heat is another alternative (especially if the undersides of the flooring are accessable)---this approach has also become very popular recently---Google "radiant floor heat" for numerous sites on this topic---radiant heating tends to be more expensive as an installation, but once in, provides the ultimate in comfort & fuel savings.

Another alternative that forced hot water heating affords is that one can mix and match any one or all of the convector types in the same system; there's nothing stopping you from having say, a kickspace heater or two at the base of kitchen cabinets, stainless steel convectors in the living room, towel warmers & kickspace heaters in the bath, and a radiator, or beacon-morris or myson convector elsewhere---they all accept hot water piping to produce plenty of heat---it's this amazing diversity and flexibility that makes hydronic heat so attractive to so many people.

Many women don't like the idea of baseboards covering most, if not all of the exterior walls of a room, because of appearance issues, and the limited options for furniture placement that it provides.

However, I would definitely get a quote that includes mostly baseboard, it's an even heat, the installation is low cost & not labor intensive, and the baseboard itself is low cost.

Another issue is to decide if you want series loop piping or a one-pipe loop that would allow you to shut off or turn down certain convectors---this is usually of issue in the bedroom, where people have comfort problems if it's too hot or too cold---check out the different piping arrangements available at the "high performance" site below---the monoflow and 2-pipe arrangements are amenable to shut-off valves on some or all convectors, while the series loop is not.


Re: Valve to convert one-pipe steam rad to hot water

Wow, NashuaTech, that was incredibly helpful. Thank you. The contractors have been called and I now can ask about different methods for different parts of the house. I'm curious about radiant flooring.

Thanks again for the information and the links.
Thank you also to Sten.

Re: Valve to convert one-pipe steam rad to hot water

Before the 1920s, most steam contractors used cast-iron, column-type radiators. Those are the free-standing ones with the real wide sections. Column radiators were perfect for steam heating because they had a lot of internal space and they allowed the steam to rise up and displace the heavier air. In the case of one-pipe steam, the air worked its way out of the radiator air vent. With two-pipe, the air escaped through the steam trap (or that old Vapour gizmo) and left the system through a vent somewhere down the main. Having a radiator with lots of internal space also allowed room for the condensate to get out of the way of the steam.

Re: Valve to convert one-pipe steam rad to hot water

Why have you ruled out simply getting a new steam boiler? It seems like the most straight-ahead approach.

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