Best small gas steam boiler

ethicalpaul

I've been looking around at options for when I replace my Utica 112k in a year or two (currently oversized by about a third, see https://docs.google.com/spreadsheets/d/1FdCNdPmlsMrp2lyTAtQhc33JdG4I5eDrKkYT0dTm_pA/edit?usp=sharing )

My house is small and compact, I think a 75k would be about right. Not all manufacturers go that small. Utica does but I have read that smart people here hate that Dunkirk boiler design, although mine seems to be doing quite nicely, even with its sub-optimal single steam output piping option.

I have heard about slant/fin and their nice wet base design, but I'm not sure what model that is...only their Galaxy comes with a gas burner, but it seems like I have read that people are maybe ordering their Intrepid model and swapping out the oil burner for a gas burner that is highly thought of. People kind of casually throw around the names and so it's hard for me to tell if it's the manufacturer or the model, but I have seen something mentioned called a Megasteam and EZ-gas. Will the manufacturer ship it without a burner at a discount? How to find out what burners can be bolted onto what boilers?

The Weil-McClain EG-30 looks promising. It is a chunk more expensive than others but I know it's well thought-of.

My priorities:
- Build Quality
- Ease of install/maintenance (I plan to install and maintain myself)
- Efficiency
- Price (It's a bummer that everything steam costs more)

Thanks!

ethicalpaul

Nothing like asking a question to help one understand and learn things...so here's the EZ-gas burner conversion unit from Carlin. It lists what it works on, and it has a flexible bolt-on flange design: http://carlincombustion.com/wp-content/plugins/pdf-viewer-for-wordpress/web/viewer.php?file=http://carlincombustion.com/wp-content/uploads/EZ-Gas-Pro-Brochure-060817-web.pdf

So people pick the best oil-burning boiler and put this on it I guess. But is that worth the trouble over the best gas-burning boiler?

This design must have advantages over the flat-base burner of my Utica which looks to be about as engineered as a backyard grill.

ethicalpaul

OK I see MegaSteam is a boiler (oil only ) but it looks like it doesn't go small enough for me: https://files.gitshare.io/link/p8S0cTfQYR8/MegaSteam Product Data Sheet.pdf

mikeg2015

You need to size based on the total radiation installation in the house. Then it needs to be balanced so it heats evenly, then the mains need to be vented fast to steam gets to each at about the same time.

I personally think that 1.33 pickup is a little excessive, and can go a lot lower for several reasons but that should be a maximum size.

ethicalpaul

Thanks @mikeg2015 but have a look at my google spreadsheet linked above, I have all the EDR listed there. My main is vented. I'm comparing net BTU vs net BTU to determine my target boiler size of about 75k (input).

coelcanth

burnham independence IN4 or IN5 are in that range

ethicalpaul

Thanks, I’ll look at them. Do you like them?

coelcanth

well i am just a homeowner like you..
not much experience,
but i have no complaints with my IN6 yet..
just starting it up for the second season now.

i think the IN5 has two riser tappings out the top of the boiler, which might help make drier steam. also seem to remember reading these use cast iron push nipples between boiler sections as opposed to rubber in the W-M boilers ?? some feel rubber seals lead to durability issues...

i do see posts here, though, that characterize the Burnham's as hyper sensitive to oils, and requiring frequent skimming...
and for some reason, they did not include a skim tapping (my manual says to remove relief valve to skim)
although i think the current models may have added an extra tapping

Fred

The Burnhams don't have to be skimmed frequently but they MUST be skimmed with any little piping change/fix where other boilers aren't that sensitive to small amounts of oil off of say a new elbow or small section of pipe. I think many of the Pros here shy away from the IN series of Burnhams because they seem to be subject to early rot in 8 to 10 years. They seem to be very sensitive to water quality and I believe the documentation has some info on water conditioning. The Pros do favor the Megasteam but Burnham voids the warranty if anyone were to put a gas burner in them. I have an older Burnham (35 years old) and I have had good service from it but again, if I need to replace any little pipe, I know I will have to skim it. Mine also does not have a skim port and I have to use the PRV tapping (I put a nipple and a Tee on that tapping. PRV is mounted on the top of the Tee and I keep a plug in the end of the Tee so that it is ready when needed. Because that tapping is only 3/4" a very, very slow skim is required to be effective.

ethicalpaul

Thank you both. I wonder if anyone throws a tee or nipple or elbow in the dishwasher before installing it to help with that!

ethicalpaul

Fred said:

The Pros do favor the Megasteam but Burnham voids the warranty if anyone were to put a gas burner in them.

So whenever one of the wallies puts in an EZ-Gas, the boiler warranty is instantly voided? How does that conversation go with the customer??

ethicalpaul

Looking at @KC_Jones's DIY job, I guess I should just go with WM. I can tell that guy doesn't mess around

Dave0176

Weil-McLain is my top choice, however I’ve installed Burnham Independence boilers, Crown boilers and Peerless. My opinion is you got to be careful with Burnhams on the east coast, there very sensitive to high chloride water. I’m not a fan of Utica, Dunkirk or any ECR gas steam boilers with side steam outlets.

Depending on where you live Weil-McLain also has a rebadged boiler called Williamson, Thermoflo, Union Steam and Genesis. These are identical to the EG series except the dark green paint and sell for about 20-30% less.

Dave0176

ethicalpaul said:

Fred said:

The Pros do favor the Megasteam but Burnham voids the warranty if anyone were to put a gas burner in them.

So whenever one of the wallies puts in an EZ-Gas, the boiler warranty is instantly voided? How does that conversation go with the customer??

As far the boiler warranty goes remember all the manufactures only warranty manufacturing defects for 10 years, you get a one warranty on everything else.

ChrisJ

After doing my research in 2011 I went with a Weil Mclain EG series.

Now days I'd go with a Williamson, just because it's the same exact thing but much cheaper.

My personal preference for sizing is to add up all of your radiation and then calculate the piping loss and add it to the radiation. Then, look at the boiler's DOE output (gross output) and try to find a boiler that is fairly close to your radiation + piping losses plus a few percent.

In my case, I'm 10% over my radiation. 104,000 btu/h DOE output with 392 EDR connected. 392 x 240 = 94,080 btu/h. That leaves me almost 10,000 btu/h for piping losses which is more than enough for my system.

Steamhead

ethicalpaul said:

Fred said:

The Pros do favor the Megasteam but Burnham voids the warranty if anyone were to put a gas burner in them.

So whenever one of the wallies puts in an EZ-Gas, the boiler warranty is instantly voided? How does that conversation go with the customer??

We've all concluded that Burnham/US Boiler has their collective head up their collective tuchas on this. The MegaSteam is the best residential steamer, hands down, and with oil heat in decline (don't get me started on that), it's foolish to limit MegaSteam sales this way.

But in your case, you're looking for a small boiler. The smallest wet-base steamer I know if is the Weil-McLain SGO-3, which at 354 square feet is too big for your house. They don't make smaller ones because oil burners can't fire much lower than that.

You might look at the Force boilers which are sold through Ferguson. These are re-branded Crown units but the prices are better. The smallest one (FORCESTM03) is rated 175 square feet. You'd want the next size up (FORCESTM04)at 263 square feet.

ethicalpaul

ChrisJ said:

After doing my research in 2011 I went with a Weil Mclain EG series.

Now days I'd go with a Williamson, just because it's the same exact thing but much cheaper.

My personal preference for sizing is to add up all of your radiation and then calculate the piping loss and add it to the radiation. Then, look at the boiler's DOE output (gross output) and try to find a boiler that is fairly close to your radiation + piping losses plus a few percent.

In my case, I'm 10% over my radiation. 104,000 btu/h DOE output with 392 EDR connected. 392 x 240 = 94,080 btu/h. That leaves me almost 10,000 btu/h for piping losses which is more than enough for my system.

Thank you so much. So the reason you do that is to have a more accurate total EDR for your personal situation and not rely on the manufacturer's piping pickup?

Fred

ethicalpaul said:

Thank you both. I wonder if anyone throws a tee or nipple or elbow in the dishwasher before installing it to help with that!

I tried boiling a few fittings in a pan of water with some dishwashing liquid once. Didn't make a bit of difference, in my case.

Fred

ethicalpaul said:

Fred said:

The Pros do favor the Megasteam but Burnham voids the warranty if anyone were to put a gas burner in them.

So whenever one of the wallies puts in an EZ-Gas, the boiler warranty is instantly voided? How does that conversation go with the customer??

As far as I know, no one has installed a gas burner on a Megasteam. Along with the warranty issue, there is also a concern about liability.

Steamhead

I know of cases where it has been done. No problems, and a great gas-fired steamer.

BobC

i installed a Smith G8 about 6 years ago and would have preffered the MegaSteam but Burnham would not sell it without the oil gun at that time. I spoke to Burnham at the time and they were adamant about it being oil only - you really can't fix stupid.

From what I've seen the megaSteam is very robust so the loss of warranty wouldn't concern me (others may differ). I think the liability thing is a bit of a stretch, people have been putting conversion burners into old oil fired boilers for over 50 years, as long as it's done correctly it should not be a concern.

Bob

ethicalpaul

Thanks all. It sure sounds like lawyers are in charge over there, not that I blame them, it’s their company but a wet base seems like such a nice design.

But maybe it’s not that big of a difference to really put too much thought into. But I seem to have an unlimited ability to ponder this stuff 😂

ChrisJ

ethicalpaul said:

ChrisJ said:

After doing my research in 2011 I went with a Weil Mclain EG series.

Now days I'd go with a Williamson, just because it's the same exact thing but much cheaper.

My personal preference for sizing is to add up all of your radiation and then calculate the piping loss and add it to the radiation. Then, look at the boiler's DOE output (gross output) and try to find a boiler that is fairly close to your radiation + piping losses plus a few percent.

In my case, I'm 10% over my radiation. 104,000 btu/h DOE output with 392 EDR connected. 392 x 240 = 94,080 btu/h. That leaves me almost 10,000 btu/h for piping losses which is more than enough for my system.

Thank you so much. So the reason you do that is to have a more accurate total EDR for your personal situation and not rely on the manufacturer's piping pickup?

I did that because hissing vents annoy me as does rapid changes in temperature. When I say "hissing" I don't mean whistling, I mean the sound they make at 0.5 PSI. To me, a steam system should be practically invisible. Not noticed by anyone by sound or feel. Meaning, the building should just be comfortable and you should never know if the boiler is on or not. Basically, the complete opposite of forced air.

I'm able to run TRVs on 5 out of 10 radiators and yet never build enough pressure to make any vents audible. I can also do a 10 degree recovery and still not have a problem because the radiators condense the steam as fast as the boiler makes it.

The downside is it can be a lot more difficult to balance. It takes time and patience. But once you get it right, it's a beautiful thing.

My system was balanced fairly well without the TRVs. I added them to deal with changes such as the oven running, sun, wind etc. To me, it's awesome when the two kitchen radiators stay cold because the oven is running. Or when a bedroom doesn't get any steam all day because it's sunny but then heats normal at night.

I too spend a lot of time pondering things. Some claim I'm really picky but I think they're wrong.

KC_Jones

ChrisJ said:

I too spend a lot of time pondering things. Some claim I'm really picky but I think they're wrong.

We can't classify you as picky, you are on a different level from everyone else.

ethicalpaul

You know, @ChrisJ I too am bothered by my "hissing" vents, and I put "hissing" in quotes because just like you said, it's not from steam leaking from them (I think the normal thing that people think of when they hear that word), but it's just from the air escaping. Of course it's especially bad on my 2nd floor radiators that have to move all the air from the risers (I am on the lookout for an elegant "riser vent" setup like one I saw in Dan's book)

And it's at a nice low pressure: as you say, under .5 psi, but every vent I have tried seems like it was engineered to make as much noise as possible! Some even whistle!

The conventional wisdom here is "vent the mains fast and the radiators slow". But in order to vent the radiators slowly, you have to limit the airflow from their vents, and that causes the whistling (at least in my experience). And I'm currently thinking, unless it's for balancing purposes, "why vent the radiators slowly at all?"

I have experimented with just removing the orifice fitting from maid-o-mists, but even that opening whistles. I will solve this!

* I know some of this is from my boiler being oversized by 37% or so...if it were making steam slower, then the air would be more gently pushed out of the vents

ethicalpaul

PS: @ChrisJ can you send a link to your TRV of choice? I'd like to see what you are working with.

ChrisJ

ethicalpaul said:

PS: @ChrisJ can you send a link to your TRV of choice? I'd like to see what you are working with.

I have two Danfoss and three Macons. They all work as long as you do enough cycles and keep the pressure low. 2 CPH is a must with them IMO.

The Danfoss comes in two pieces, and you need a vent. I used straight Gortons. The Macon seem like better units to me and I kept their original vents, but they also suited the locations. I think they're similar to a Gorton #5 as far as speed. You must get the radiators balanced enough without a TRV otherwise it won't work.





I don't believe in venting radiators slow. I have Gorton C's on two of mine.



I updated this, but don't have a copy with me. The changes are I added a TRV to the livingroom and two in the kitchen. I also got rid of the Gorton 6 on the pipe in the bedroom and swapped the radiator vent with a Gorton 5. The pipe being vented did help, but it wasn't necessary to have the slow #4 on the radiator with the TRV so I didn't need to vent the pipe separately anymore.

PMJ

@chrisj said "To me, a steam system should be practically invisible. Not noticed by anyone by sound or feel. Meaning, the building should just be comfortable and you should never know if the boiler is on or not".

Just for the record, vacuum operation is dramatically quieter than vented. I literally have no idea if my boiler is running or not.

And from the standpoint of rapid temperature change, that you can know by how fast the calls are satisfied. The shorter that time is, the faster the temperature is changing. The longer the calls are, the less people will notice the temperature change.

ChrisJ

PMJ said:

@chrisj said "To me, a steam system should be practically invisible. Not noticed by anyone by sound or feel. Meaning, the building should just be comfortable and you should never know if the boiler is on or not".

Just for the record, vacuum operation is dramatically quieter than vented. I literally have no idea if my boiler is running or not.

And from the standpoint of rapid temperature change, that you can know by how fast the calls are satisfied. The shorter that time is, the faster the temperature is changing. The longer the calls are, the less people will notice the temperature change.

I'll gladly put my vented setup against your vacuum setup for sound comparison. The entire system.

I'm betting your solenoid clicking will win me the challenge.

brandonf

I haven't brought in my contractor of choice for an estimate yet but through research and professional opinions I'm leaning toward a megasteam with a Carlin ezgas, and use a bolt-on hot water coil to pre-warm the water feeding my standalone dhw heater for a little more fuel savings. 😎

PMJ

ChrisJ said:

PMJ said:

@chrisj said "To me, a steam system should be practically invisible. Not noticed by anyone by sound or feel. Meaning, the building should just be comfortable and you should never know if the boiler is on or not".

Just for the record, vacuum operation is dramatically quieter than vented. I literally have no idea if my boiler is running or not.

And from the standpoint of rapid temperature change, that you can know by how fast the calls are satisfied. The shorter that time is, the faster the temperature is changing. The longer the calls are, the less people will notice the temperature change.

I'll gladly put my vented setup against your vacuum setup for sound comparison. The entire system.

I'm betting your solenoid clicking will win me the challenge.

Not using the solenoid these days. Just the simple water check valve... in the garage. Going for simplicity now ... things anyone can do. So there is no clicking, and there is no opening to the system in the living space from which to hear anything at all. I admit, 2 pipe is an unfair advantage in this regard.

ChrisJ

PMJ said:

ChrisJ said:

PMJ said:

@chrisj said "To me, a steam system should be practically invisible. Not noticed by anyone by sound or feel. Meaning, the building should just be comfortable and you should never know if the boiler is on or not".

Just for the record, vacuum operation is dramatically quieter than vented. I literally have no idea if my boiler is running or not.

And from the standpoint of rapid temperature change, that you can know by how fast the calls are satisfied. The shorter that time is, the faster the temperature is changing. The longer the calls are, the less people will notice the temperature change.

I'll gladly put my vented setup against your vacuum setup for sound comparison. The entire system.

I'm betting your solenoid clicking will win me the challenge.

Not using the solenoid these days. Just the simple water check valve... in the garage. Going for simplicity now ... things anyone can do. So there is no clicking, and there is no opening to the system in the living space from which to hear anything at all. I admit, 2 pipe is an unfair advantage in this regard.

Yes, 2 pipe is an advantage for sure.
However, to put the noise my vents make into perspective, remember my pressure at the boiler stays around 0.25" WC when sending steam out to the radiators and venting my mains.

0.009 PSI at the boiler, which means quite a bit less at the vents due to friction losses.

Once the radiators start condensing a decent amount I'm not entirely sure what the pressure is at the actual radiator vents. I assume it fluctuates between a slight positive and slight negative pressure.

On really cold days when the radiators stay pretty hot I see 0.75" at the boiler.

ethicalpaul

Thanks @ChrisJ for the info!

@brandonf that sounds pretty good! I think the smallest megasteam is too big for my house I like your pre-heating idea. I had a tube solar array on my roof in CT that warmed a buffer tank that fed into my electric water heater. I think it would have paid for itself in about 372 years, but I moved after 2 LOL

My current number one is the Williamson GSA-075-N-IP available from several online sources, or I'd buy one from one of the folks here if they are interested.

I also need to have a consulting visit at my house in Northern NJ to tell me what is messed up and what I should focus on.

Tim McElwain

As far as installing conversion burners I have installed over 3,500 atmospheric or power gas conversions in my career. I simply pick up the warranty myself. I have never in all these years had to make good on a warranty issue caused by installing a conversion burner. This includes Burnhams by the way. If you know what you are doing and make sure to do a combustion test when completed you can't go wrong.

ethicalpaul

Thanks Tim, makes sense. Yep, I'm going to have a technician come to do that. I don't think I'll have to do a conversion but I sure would like to have 86% efficiency instead of 80-82, but I don't think there's a wet base model small enough for me

PMJ

@chrisj, I do believe you have your system running just about as quietly as open vented single pipe can possibly be which is certainly very quiet.

You are correct that the pressure in a condensing partially filled radiator is fluctuating slightly above and below atmospheric - even with an oversize boiler feeding them. I know this because I have become very interested in those conditions and have done a lot of testing. I am learning that what to me is a surprisingly wide range of demand can be satisfied with a surprisingly small change in radiator fill level.

But this should probably go on another thread.

Fred

When I mentioned the Liability issue, I wasn't suggesting that it was related to a real risk using a gas gun on the Megasteam. My point was that many (if not most) contractors/installers aren't willing to assume the liability for doing something the manufacturer says don't do, in return for the little profit they make on that install. Basically Not worth taking the risk, real or otherwise. It's a shame that Burnham won't say exactly why they won't support a gas gun on the Megasteam. The unknown is what is cause for pause, especially when the return is so small for a contractor.

ethicalpaul

Thanks Fred, that’s how I understood your meaning.

I think you’re right, but sometimes pros (and interested HOs like myself) do things differently in their own homes than would be profitable out in the world (I imagine you know this)!

Tim McElwain

To the best of my knowledge Burnhams reasoning is that they do not have any way of knowing the expertise of the installer. That being said they do not want to assume responsibility for any failure.

They could probably make an argument that you are changing the design of the equipment and therefore need "third party testing " to be done.

ethicalpaul

Tim McElwain_4 said:

To the best of my knowledge Burnhams reasoning is that they do not have any way of knowing the expertise of the installer. That being said they do not want to assume responsibility for any failure.

They could probably make an argument that you are changing the design of the equipment and therefore need "third party testing " to be done.

That's fair. So they should sell a gas version of it

KC_Jones

Tim McElwain_4 said:

To the best of my knowledge Burnhams reasoning is that they do not have any way of knowing the expertise of the installer. That being said they do not want to assume responsibility for any failure.

I am assuming they have never seen some of the steam piping that has been applied to their boilers?