Redo steam

Wonky

I have an 80-year-old 5000 square foot colonial that has the original coal boiler.  It was converted to oil a long time ago, but I use the gas-powered hot air that was recently installed because I can tear through oil using that ancient burner faster than they can deliver it (based on just feeling the pipes and chimney, I would not be surprised if its actually efficiency is below 10%).



Anyway, I've been looking at different boilers to replace it, but I have one question:  can any gas- or oil-fired burner be used for steam or hot water radiators?  I have steam, and I don't think I'm interested in converting to hot water.

clammy

Boiler or burner

I was kinda unclear if you plan on replacing the boiler or just the burner?If your still using the original coal boiler and upgrading the burner don't plan on saving much if you meant the complete boiler then yes any boiler could be used but it would be best if you had a professional come out and evaluated your system to properly size your new boiler and to make sure that there would not be other issues like big differences in water levels of the old boiler to the new this can cause problems if it is overlooks it's important .Also if a new steam boiler is to be installed your return piping should be looked at to see if there are any issues (buried wet returns ) Even though you have said that it burns alot of oil there may be loads of reasons why like many inches of mud in your boiler,lack of proper combustion side and water side cleaning  and no main vents.As i see it in a home of that size no matter whet  fuel you use you an except a decent size bill but in my experience on larger homes oil and steam always seemed to be fairly inexpensive  way to heat  with not many moving parts .Just make sure that the people who replace your boiler have taken the right steps to install your system properly.check out the resources pages on this site they will help you allot and always remember that a correctly installed steam boiler is not cheap and a cheapened price will usually come with issues that the higher priced install usually will not have and make sure that the person who does your replacement is well versed in steam and has some reference of other steam systems like your that they have replaced also make sure that main vents are added ,being that you may not have any ,most older coal fired system did not have any and this will effect your system operation and fuel usage especially since your not burning coal any more.On some conversion i have done in the past the HO have seen dramatic reduction in there fuel usage and the comfort level in there home .These where conversions from old coal fired boilers which at some time where converted to oil and then removed and update with a oil fired steam boiler (nothing special standard pin type single pass boiler) and had seem great savings in oil consumption at least 20 to 30% but most also needed alot of work in the first place(no maintance for years)best advice i can give you is to learn all you can and find a knowledgable contractorand do what he reccomends peace and good luck clammy

Jamie Hall

Go for it

The building I supervise went through that sort of thing about 10 years ago.  A good replacement boiler -- and there are a number of them -- is almost guaranteed to cut your oil usage in half, if not further.  (the records on this building show a cut of about 70% in oil usage, which is, to put it mildly, dramatic).



Clammy's advice is all good.  Don't just replace the burner, replace the whole thing.  It will pay you back.  However, get someone who knows steam to come and evaluate the system as a whole, and to do the installation if at all possible.  It is possible that there are other things which will need attention (like wet returns) in the process, and he will know enough to attend to critical details like getting the sizing right, and getting the water level of the new boiler at the same elevation as the old one (really important) and so on.  You may be able to find a really good pro from Find a Professional on this site -- input your state, not the zip code, as the zip code function doesn't always work as well as might be hoped.



And as he says, good luck!  We'll all help as much as we can.

Steamhead

Here are some modern residential steamers

in various sizes. The first one is most like you'd probably need given the size of your house, a Weil-McLain 80 series. Then we have a Slant/Fin Intrepid, Smith 8 series and a Burnham MegaSteam. All but the Burnham are factory-approved to burn oil or gas.



What model of boiler and burner do you have now? Is this a one-pipe or a Vapor system? Post some pics if you can.

Wonky

more details

Thanks for everyone’s willingness to help out.  I guess I should clarify my issues and give more detail.  Also, I meant replace the entire boiler, not just the burner.  Anyway, here goes:



I have four units that supply heat to this house, which is a 1925 colonial with a large addition and a partially finished basement and partially finished attic.



1.    Two fairly new, idential Rheem gas-fired hot air units that use the same ductwork as the two air conditioners.  The unit in the attic supplies the entire third and second floors, and the unit in the basement supplies the entire first floor.  The only finished part of the house that isn’t served by one of these is the finished basement, although that could easily be remedied, since the ductwork appears to have been run there and simply capped off (I don’t know why).  This is the main way I heat my house now, since these units work reliably and heat pretty much everywhere my family hangs out.  The only problem is that I don’t like hot air heat.

2.    The boiler I originally mentioned, which is a single-pipe, oil-fired steam unit that serves 18 fat, terrific old radiators on the first, second and third floor of the house (not including the addition).  I rarely use this because it can tear through phenomenal amounts of oil in just a few days.  But when I have, it has been terrific:  the burner is mildly noisy, but the system is even, comfortable and there is very little pipe noise.  It is obvious when the radiators are on why you guys say a well-working steam system can be terrific.  A few of the radiators have adjustable valves (or whatever you call them) on them.  None of them leak, but they don’t seem to do anything either.  It would be nice to be able to replace them with things that would allow me to modulate the heat to, say, the 3rd floor guest room when no one’s there.  There is also a giant radiator hanging from the ceiling of the unfinished garage/basement (outside the thermal envelope).  The wood-handled knob to close the valve is stuck in the open position.

3.    A Repco gas-fired unit that serves four zones for baseboard hot water heat.  One of the zones has been capped off (an uninsulated porch where the pipes probably froze and should not have heat anyway); the finished basement (the only heat there right now); the first floor addition (also served by the hot air, but not by the steam radiators); and the second floor addition (also served by the hot air, but not by the steam radiators).  This sytem is in good working order (I recently had the expansion tank and a couple of other external components replaced), but I have no idea how much it’s costing me to use because I use gas for cooking, domestic hot water and the hot air units.  The team that recently serviced it said it’s an okay unit that’s doing fine, but that it will be very difficult—or impossible—to get parts if needed in the future.



I also have a 12 (?) year old standard gas-fired tank for domestic hot water.  I would like to replace it as well, and figure that whatever solution I consider for the steam system should include domestic hot water.



So a few questions/issues:



1.    Should I stick with oil or use this opportunity to switch to gas if I replace the boiler?  There is something that appeals to me about being able to heat all or nearly all of my house with either fuel (I’m not getting rid of the hot air system because of the A/C, so it can always serve as a backup), although if there is a big advantage to going “all gas” that’s more important.  Unlike other parts of the country, getting oil in New England does not appear to be a problem.

2.    I will likely eventually gut the addition and re-do everything there, so I don’t think I’m looking for a solution now that would also replace the Repco unit.  Besides, I’m not sure any system would be able to serve the steam radiator needs and the hot water radiator ones.  So I figure I’ll use the Repco unit to heat the addition until it’s time to redo the addition.  Then perhaps I’ll get something for radiant floor heating.  If you have any suggestions for what would be good to think about for that future plan, fire away.

3.    I am intrigued by the possibility of buying a “tried and true” boiler from a brand that has a good reputation (Viessmann, for instance) but something newer like the EK System 2000 looks like it was almost made for my needs.  Obviously, any thoughts on these things would be great.

4.    Is there a chance that any solution for my steam system could be zoned?  Please assume that I don’t plan to tear up walls in the old part of the house to run more pipes, etc.



Thanks in advance for all your help.  If you’re crazy enough to have read this far already, please accept my sincere appreciation for your time.

Steamhead

I see a couple of things

you could upgrade on the steam system: first, the main vent looks way too small for the pipe that it's on. It looks like a Dole #5 or 6. Measure the length and diameter of each of your steam mains and we can tell you what vents you need. Proper main venting reduces the warming-up time so the boiler runs less.



Second, the Mills boiler was one of the best in its day, though it cannot equal a modern boiler for efficiency. What is its rated capacity? How does this compare with the amount of radiation you have? What firing rate is the Beckett burner set up for?

Ross_7

Velocity

Hi Frank,



I was just wondering if you have any velocity problems with the Slant-Fin in the middle. With just the one outlet. Thanks!

Ross

Steamhead

Nope

it's a 3-inch outlet so that keeps the velocity down. Larger models have two outlets.