Choosing the right gas-fired steam boiler...

effiweefewelp1875291

Hi everyone,

I've read many of the posts in this forum and managed to learn a lot, but I feel like I'm still comparing apples and oranges. Here's the scoop: I have a ~1500 sq ft house (built in 1928) with an oil-fired steam boiler (probably installed in the 1960s). I'd like to switch to gas. I'm finding it very hard to get reliable information about the various boilers, and I'm getting conflicting information from the various contractors that I've had come give estimates. So here are my questions:

1) Are there particular brands of boilers that I should consider? Or avoid? I've read that I should avoid Weil-McLain (because of neoprene gaskets) and I've heard from one contractor that I should also avoid Crown since they changed their design (recently?). I've had Weil-McLain, Crown, Utica, and New Yorker (made by Burnham) recommended to me. Are there others that are conspicuously absent? If a company recommends a "bad" boiler should I avoid using that company or should I ask them to install a different model?

2) Does it matter whether copper or cast iron pipes are used? Is it more/less important for suply versus return pipes? I only have ~10-15 feet to plumb, so I'm not terribly worried about cost--juts repair. I've had one contractor say he won't use copper (because it corrodes) and all the others use cast iron to attach to the boiler then switch to copper. What's important?

3) Of the five contractors that have come out thus far (I'm looking for the right company, not the lowest price), three have measured the radiators (albeit differently each time). One told me that my radiators were 279 (of what, he didn't say, but I'm guessing that it's a measure of the sq footage that the steam "covers"). All five companies have recommended boilers at 112 btu or 150 btu. Is the difference critical? How do I decide? Should I measure myself? If so, can someone tell me where to find directions?

4) I have an unfinished attic that I plan on finishing in a couple of years. It currently has no heat/pipes and would require the equivalent of two average-sized radiators. Can I heat this space with the new boiler? And how do I need to consider this when I choose the btu for my new boiler? (Dan, I read the tech topic one on this, but I'm still not clear).

Many thanks in advance for whatever help or advice you can offer. This site has the best responses of any I've found!

Nikki

Al Corelli_2

Boiler Choice

I'm in between service calls, so I'll answer number 1

ANY of the boilers listed will do a good job.

My preference for atmospheric gas/steam is only for two boilers. These boilers have never given me any trouble during or after installation. I have installed many of these.

First choice: Burnham.

Second Choice: Weil McClain EG series.

Normally, I do not care for the WM boiler line, EXCEPT for the EG. This boiler has stood the test of time, and is of outstanding design.

Better yet, why not go for a Smith G8 Boiler. This is a "wet base" boiler that uses each therm of gas more efficiently than an atmospheric boiler. Plus, when the price of gas catches up and surpasses oil, you can install an oil burner without any fuss.

I'll touch on number 2.
Do not use ANY copper on the supply or return of a steam boiler.



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Steamhead (in transit)

The first thing to do

is to do a heat-loss calculation on the proposed attic renovation. This will nail down the amount of radiation you need up there. Under Resources at the top of the page, click on Heat Loss Calcs to get a free program from Slant/Fin that will run on any Windows computer. Divide the BTU loss of each room by 240 to get the radiator size in square feet.

Once you know this, add that amount of radiation to the current amount you have (279?). Then select a boiler based on that figure.

As to which boiler to recommend- too bad you're looking at gas, because the oil-fired Burnham Mega-Steam is far and away the best residential steamer out there. They don't offer a gas burner option for it (yet?). Next best is the Smith G-8 series, which is their 8 series wet-base oil-fired boiler with a Carlin gas burner in it. This uses roughly 6% less gas to achieve a given steam output than the typical atmospheric boiler.

Note that to see this, you would need to figure what percentage the boiler's DOE output rating is of the Input rating. The typical atmospheric boiler is 80-81% or so, the G-8 is 86%. And this has nothing to do with AFUE.

Here's a pic of a 6-section G-8 we installed recently. Your house may need a 4- or 5-section G-8.

Copper should NEVER be used on pipes that carry steam. The soldered joints can break. On return lines that only carry water, copper is OK.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

effiweefewelp1875291

Another query, then...

Would either of you recommend that I stay with oil? It would mean a new oil boiler AND a new tank (outside one is at least 35 years old and buried...a veritable time bomb). The oil makes me a little uncomfortable because of the possibility of a leaky tank, and because when I flush the current boiler, it smells like gasoline and looks filthy. And, of course, I'm paying out the wazoo for oil to heat my home.

So gentlemen, what would you do in my shoes? What's the cheapest way to go? What's the best investment in the long term?

Also, I'm not entirely clear about what I'm supposed to be calculating for the attic. I was under the impression that because I'd be using the hot water from the boiler for that area, that I shouldn't be calculating the attic as part of the same load. I was reading "Like to run a hot water zone off a steam boiler?" (Tech Topics, page 7). Did I get it totally wrong? Does this not apply to me?

effiweefewelp1875291

So, the EG series is more reliable?

Hi Al,

I was just looking back over the estimates and the fellow that suggested the W-M did choose the EG series. However, I've heard from several places that the rubber/neoprene seal in W-M boilers is very unreliable...does this line not use this? I have no idea where this seal is supposed to be, so I'm not sure how to look it up in the product literature.

Thanks!

Steamhead (in transit)

All W-M boilers

have rubber/neoprene/elastomer seals between the sections.

Nikki, why don't you post some digital pics of your current boiler, also the end of each steam main? We might see a few things that you can have fixed right away without having to wait for a new boiler, and that will lower your operating costs.

Regarding oil vs. gas- I prefer oil since oil suppliers are in competition, whereas most gas utilities are unregulated monopolies and can raise prices at will. The Smith 8 series boiler can be had from the factory with either oil or gas burners.

Which "Maplewood" are you in- New Joisey?



To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Al Corelli_2

No Trouble

I have had no trouble with ANY manufacturer's elastomer seals.

Try to get some pictures posted of your system as Steamhead suggested.

The Smith 8 Series is a great choice for efficiency.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

kevin coppinger_4

the whole...

rubber/ neoprene thing is a marketing BS gimic that some people will use to bad mouth a product...Smith and Weil have used these for a LONG time w/o issues. More than anything else the installer is the most important part. A good boiler improperly installed will give yu bad results....kpc

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

effiweefewelp1875291

Got pics...of what, I have no idea.

OK guys, you asked for it...here are pics. I hope that they come through with titles or labels...or if they don't that you can still make sense of them. I REALLY appreciate all of your feedback!

Nikki (from Maplewood, New Joisey)

effiweefewelp1875291

W-M correction

Thanks, too for setting me straight on the elastomer seals. I'm really glad for your recommendations. For what it's worth, the fellow that recommended the W-M boiler was the only one that made a point of saying that he doesn't use copper pipes. He's a rather grumpy guy, but I can deal with that...

Steamhead (in transit)

Well, I've seen a LOT worse

than that American-Standard A-34. This series of boilers were built like tanks, as anyone who has ever installed or replaced one will attest.

It looks to me like whoever put that in really knew his stuff. The header looks proper. I think if you installed a Smith G-8, you could re-use that header.

Now, if you decide not to replace that boiler there are several improvements that a pro can make: 1- remove the original DH-series burner and install a high-speed flame-retention type. A Beckett AF or Carlin 100CRD is fine for this boiler, don't need an AFG, EZ-1 or Riello on one like this. Reduce the firing rate by 20% or so, you'll still get the same amount of heat input since the new burner is more efficient.

2- if the firebox is still the original stainless-steel type, replace it with a "bathtub" type made of Kaowool. This will warm up quicker and not deform under the newer burner's hotter flame.

3. Replace that old Watts low-water cutoff (black cast-iron device in left side pic)- it looks kind of rough, and if it sticks and the boiler fires without enough water in it, it will crack.

Now as to the system- I see in the Pipe pic that there's a tee at the end of the main with a plug in it. There should be a vent there- this will help the steam distribute faster and with less pressure, so the boiler will run less. Measure the length and diameter of the main and we can tell you what vent is needed. If that is not the only steam main in the system, measure the others too. This should be done whether you replace the boiler or not.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

effiweefewelp1875291

Measuring the pipes

Thanks Steamhead.

Are you saying that I should measure the length of the pipes (yes there are two) from where they emerge at the boiler? And the outer circumference? I was reading elsewhere on the site about those vents, and I thought it might be where the plugs are, but I wasn't sure. Lemme see if I can find my measuring tape...

Let's just say I decide to stay with oil (I'm still very freaked out about the buried oil tank, so that would still have to be removed, and if I'm still using oil, replaced), would you recommend that I stick it out with this boiler--making the changes that you suggest, or would you recommend a new boiler? How much efficiency gain would you expect either way?

If I do switch to gas, the only change that's worth making now would be installing the vents, right?

Nikki

Steamhead (in transit)

That would depend

on whether you wanted to spring for a new oil-fired boiler. The efficiency gains you'd get by having your A-34 upgraded wouldn't equal those of a newer boiler- ESPECIALLY a Mega-Steam- but you wouldn't have to lay out as much money now. BTW, we don't discuss pricing here.

The American-Standard DH series burners were rather finicky, and didn't always burn clean. A modern burner, whether in a new or older boiler, when set up properly will not make any smoke or soot- period. So the boiler will hold its efficiency over the course of a season, and that would be a major gain. Soot kills efficiency.

How much improvement can you expect? This is one of those things that can be hard to predict, but we have a customer who sent us the following after we (before starting All Steamed Up, Inc) did many of the same things to her A-34 boiler- that's right, same model as yours. This was at the end of the 2003-2004 season:

"Final Statistics of the steam system upgrades!

Last year Actuals:

Gals of Heating Oil- 892.7 Degree Days 4076 Gals per degree day .219

This year Actuals:

Gals of Heating Oil - 567.5 Degree Days 4238 Gals per Degree day .1339

or 36.4% less oil for heat during a slightly cooler season.

In dollar bills, we saved $683 in oil costs.

As I said before, this isn't an exact comparison. The boiler and radiators work so much better that we were able to keep the house an average of about 3 degrees warmer than we did last year. We also saved about $300 over the season by not running extra electric heating devices."

Note that a lot of this was due to the replacement of a VERY sooty burner- now the A-34 stays clean all year. Here's the complete list of upgrades we made:

Added properly-sized main vents

Changed some radiator vents to properly-sized ones

Flushed the returns and boiler

Replaced the low-water cutoff (was stuck)

Replaced the old Sinclair Super-Flame (built by ABC) oil burner with a Beckett AF and a nozzle one size smaller (1.00-80-W)

Cleaned out the boiler's flue passages and sealed w/furnace cement

Replaced the old steel chamber with a Lynn bathtub

Fired and tuned the burner.

They would have gained some more efficiency with a newer boiler, but a good upgrade can go pretty far.

You want to do the main vents regardless of what you do with the boiler. If you do decide to switch, do the vents first.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

effiweefewelp1875291

Thanks

Wow. That's a pretty impressive gain for such an old system. I suppose I'll need to tackle the radiator vents, too at some point, but I'm already overwhelmed trying to decide what direction to go in...so much to think about!

I guess I'm lucky that it's not an emergency change, so I can afford to take the time to ask around (on this site), talk to plumbers in the area, and read the "We got Steam Heat" which I just ordered (and which looks like it'll be lots of fun to read). I'll be back on regularly when I find something I don't understand...

Meanwhile, I just want to say thanks to all of you (whether you've posted on this topic or not)...this is an awesome resource and so many of you have been incredibly generous with your expertise. It's not much, but I just bought 5 bricks as a small way of saying thank you. So, thank you.

Nikki

scrook_2

W-M gaskets

Aren't the gaskets EPDM (ethylene propylene diene monomer) not neoprene (synthetic rubber)?

EPDM is commonly used for water and steam seals, gaskets, O-rings, etc. in a variety of applications due to it's resistance to hot water and steam.

Whether elastomer gaskets are a better solution than push nipples (or graphite gaskets -- used on some commercial sized boilers) is a whole different debate!

scrook_2

grumpy...

is probably a good thing for a steam installer!

spt87

Think this upgrade would help a National US Sunray IV?

Hi,

What does everyone think of doing this same type of refresh of a National US Sunray IV hotwater boiler? I'm a couple years away from either replacing the boiler along with a major remodel of the house or tearing the house down and building a new one on the same site (trying to decide which way to go).

Steamhead (in transit)

What type of burner

is in your boiler now? Post a pic if you can......

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Al Corelli_2

Grumpy?

Grumpy?

I was not there!

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

JoeV_2

which boiler?

Doesn't Burnham own Crown?

spt87

Picture coming Friday....

Hi,

I'll post a pic on Friday (away from home for a couple days).

It has a Carlin with a stack relay (not sure of burner model - I'll scrape the dirt off an check).

For an upgrade I was thinking a Beckett AF or AFG with pre/post purge and interrupted ignition (appears to have interrupted ignition now with the stack relay). I did look and see the Lynn has a chamber that lists the Sunray IV as use case. It currently has firebrick in a circular shape.

Thanks!