Indoor boiler advice needed

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andym

Feeling the Heat
Feb 6, 2020
440
Hicksville, Ohio
Hi all. I'm new to the forum here, but have been casually (obsessively according to my sweet wife) reading up on these indoor gasifiers. Im 29 and have lifelong experience burning wood, but have just recently been made aware of a (not so) new way of doing it: the indoor boiler with storage! I'm almost convinced. I was planning to install an OWB this summer until I realized:
#1 most used units were nearly worn out and cheap or nearly new and costly.
#2 new units (even non EPA which can still be bought) were very expensive
#3 all are rather inefficient.

Im currently leaning toward the indoor boiler with storage. My first question is one I haven't seen asked yet. When you only do a 3 to 6 hr batch burn to reheat storage, does the fire go out completely? I don't like the thought of always relighting. I would much rather keep a smaller fire going all day like I do now with a EPA wood stove. Is that possible using a modulating boiler?

This is getting too long, so I'll stop for now. Any comments?
 
Hi all. I'm new to the forum here, but have been casually (obsessively according to my sweet wife) reading up on these indoor gasifiers. Im 29 and have lifelong experience burning wood, but have just recently been made aware of a (not so) new way of doing it: the indoor boiler with storage! I'm almost convinced. I was planning to install an OWB this summer until I realized:
#1 most used units were nearly worn out and cheap or nearly new and costly.
#2 new units (even non EPA which can still be bought) were very expensive
#3 all are rather inefficient.

Im currently leaning toward the indoor boiler with storage. My first question is one I haven't seen asked yet. When you only do a 3 to 6 hr batch burn to reheat storage, does the fire go out completely? I don't like the thought of always relighting. I would much rather keep a smaller fire going all day like I do now with a EPA wood stove. Is that possible using a modulating boiler?

This is getting too long, so I'll stop for now. Any comments?

Some of the lambda controlled boilers shut the air inlets at the end of the burn to help hold coals - mine does it and will still have live coals after 12 hrs but not usually after 24hrs. Since I do once a day burns this does not help me but I've found that lighting a new fire is so easy it's not a big deal.

My start procedure is to position charcoal over the nozzle, start the inducer fan on the boiler and wave a propane torch on the charcoal for about 30 seconds. With the fan running they light up very easily. Then load splits, wait for flue temps to hit about 200f and close the door. Usually about 5 minutes tops.
 
Agree. When my 2007 Tarm Solo Plus 40 shuts down after a burn, some charred coals remain. I too position those over the nozzle, add a few sticks of kindling, then a couple of handsful of wood shavings from my shop planer (could use newspaper knots) on top with some small splits on top of that for a top down start. After the start is doing well for a couple of minutes, add splits for the burn. The key to an easy start is dry dry kindling and dry wood. All very easy and fast.
 
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My Tarm is a PITA starting from cold when the unit has sat idle for a week or two. When warm it’s not so bad. From coals it gets ripping pretty good using some small splits.

I’m sure the new stuff with variable speed fans and electronic controls are vastly improved.
 
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My old time Burnham is a wood/coal design with bottom grate. It rarely if ever has coals in the bottom. As long as I have had a burn in the last 24 hours, the boiler is still warm and the stack is still warm. A relight doesnt take long. The biggest PITA is I need to store up newspapers for relights. I keep a few boxes of kindling and Amazon supplies plenty of shipping boxes. It does not take a lot longer doing a relight from scratch then with a few coals.
 
That's about what I gathered from my reading. I currently have a small stove in the basement that will heat the entire house in mild weather. After that the propane furnace kicks in. We light the fire sometime in October and keep it going til April usually, except of course if we're gone for the day. My wife doesn't work so it is easy to keep loading it during the day. However, I would prefer not to have to feed it every hour or two, and would love to get a 8 hr overnight burn. That's what really drew me to the OWB. Load it once or twice a day and that's it.

Is it possible to operate one of the modulating boilers in this manner? I know some efficiency is lost by doing it this way, but I'm not concerned about a couple %. Anything is better than an OWB afterall!

I would still install some storage capacity to act as a buffer, but not enough to hold 24 hrs worth. Does anyone have experience operating in this manner?

I would just get an add on furnace, but hooking it to existing furnace in my case would be almost as much work and expense as installing a boiler. The operation pattern of the add on is sort of what I want accomplish with a boiler. ie: adjust wood input according to heat load.
Make sense?
 
My Tarm is a PITA starting from cold when the unit has sat idle for a week or two.
It does take some time on a cold start (boiler temp down to about room temperature) to get the Tarm up to temp to start providing hot water. Remember, depending on your Tarm, or other boiler, the fire has to heat up the metal, plus 55 gal of water and nearby piping for my Tarm, to operating temp for the supply circulator to start moving hot water.
 
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I'll also add, there have been a few days when I've nursed the fire along so it makes it to bedtime before it goes out - if its early in a cold day and I need the heat. Makes for a little bit of efficiency hit. I try to put off lighting a long as possible.
 
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My Econoburn is too easy to start a fire so it's not an issue.
12 years and there has been no fires that haven't started.
My X wife had no issues in 11 years with the boiler,with me she had a buttload of issues i am sure she would have kept the boiler if she had a use for it.
This year i have a lady living in my basement and have a new girlfriend and neither of them have any problem starting the boiler if i am not around.
I have purosly tried to start the fire with minimal kindling and it still takes right off.
 
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Reading the board here for a year or so before I bought my boiler, single biggest piece of advice I picked up here, and the key to the success of my system, was the indication to get a Froling.

For cold restarts the Froling leaves a charcoal bed overnight. It shuts down at the end of burn based on something like excess O2 over 20% for x time. Most of the time you can just add fuel on the charcoal bed from overnight and if it's dry fuel, it will be gasifying rioght away, less than 90 seconds.

From there I have a direct boiler hot water supply tap to the distribution header and another to the (storage tank). Basement slab is slaved to the boiler firing and that's the heat battery for the house.

I never burn overnight but the house has a contiguous 2" ridgid foam board wrap under the siding and the thermal mass is inside the house. That was what had to happen. Very well insulated shell and the radiant slabs plus the Froling is very easy work on the Froling. If I just feed it as much as I want, the house is not over four cord / year, all heat and DHW.
 
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Thanks for all the replies so far. I have learned A LOT by just reading many of the threads on this forum. What I have read here is the reason I'm considering the indoor boiler. I wish these (indoor) companies would advertise as much as the big OWB companies do. That is the reason most people (like me two weeks ago) have no clue about indoor gasifiers. Everyone I know knows what a Central Boiler is. A Garn or Froling is a saltwater fish caught near Madagascar or somewhere, right.....?

Still waiting to hear from someone who runs a modulating boiler....
Or am I the only one who wants to do things differently?
 
The reason you dont see folks running an indoor gasifier modulating is they would be throwing away much of the efficiency and low air emissions inherent in a non modulating operation. A gasifier is designed to run hot, charge up storage and then shut off until the storage needs charging again. Newer units have some turn down capability but they still need to burn hot.
 
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Thanks for all the replies so far. I have learned A LOT by just reading many of the threads on this forum. What I have read here is the reason I'm considering the indoor boiler. I wish these (indoor) companies would advertise as much as the big OWB companies do. That is the reason most people (like me two weeks ago) have no clue about indoor gasifiers. Everyone I know knows what a Central Boiler is. A Garn or Froling is a saltwater fish caught near Madagascar or somewhere, right.....?

Still waiting to hear from someone who runs a modulating boiler....
Or am I the only one who wants to do things differently?
IMO there are only a few companies out there that produce high quality indoor boilers.
Peakbagger’s Post was spot on. Burn super hot into storage then remove what’s needed for the heating load.
In short, the modulation occurs with your pump and mixing controls. Not at the boiler itself.
It’s not like thinking of a hi tech gas boiler. My LP boiler is set up to be “dumb”. My radiant controls take care of all modulation and I don’t try modulating the few rooms that have HWBB.
Chris @ Tarm is a good source and the guys at Varm are also straight shooters. I was impressed with the honesty of both operations.
Until my wood boiler gives up I’ll run what I have but getting a high tech wood boiler will happen down the road at failure.
None of this equipment is cheap.

What do you expect your budget to be?
 
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Forget about prioritizing modulation. Or maybe I should say, forget about trying to avoid having to light a new fire every day. It really isn't that bad, and not having to think about the fire or tending it for 20 hours every day more than makes up for the 'hassle' of fire lighting. Let alone the efficiency gains and less wood you'll be needing every year.
 
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This isnt new thinking. Masonry heaters formerly referred as "Russian Fireplaces" despite their Nordic origins, dispensed with the water and were designed for short high temperate burns. Instead of water being heated up the masonry heated up and slowly gave off heat to the house. They are massive and rarely would be retrofit to a house, the house is normally designed around the heater.

Arguably the original super high efficient "stove" was actually far closer to a gasifier boiler with thermal storage. It was designed by a professor at University of Maine and was run hot as needed to heat up a big thermal storage tank. At the time an installed system was quite expensive, several times more for an installed system than conventional wood stoves. A few companies, Dumont and Jetstream tried to sell them but some shortcuts in the typical thermal storage attached to them doomed most of the installs. There is at least one Hearth.com member that has a Jetstream. Still they were at the time the most efficient and cleanest wood boilers built and still would give a run on efficiency and air emmisions to modern boilers. I expect they would be competitive with a typical gasifer installation today but they were ahead of their time. The plans for the original design are available on the internet but I expect few folks would attempt to build one as it would be difficult to insure.

If someone wants an clean and efficient modulating wood boiler they are far better lookng at pellet boiler. The state of the art for cord wood these days is installing heat emitters in the house to be able to heat the house at far lower temperature supply temperature than previously. By dropping the supply temp down to 85 or 90 degrees F compared to typical 140 to 160 F used for baseboard, the storage duration of storage tanks is efectively doubled. Add in low energy design and construction techniques and a well designed system can go days between burns even in cold weather. The low temperatrue emitters also mean that the wood can be supplemented with air to water heat pumps run off of net metered solar on days over 30 F.
 
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IMO there are only a few companies out there that produce high quality indoor boilers.
Peakbagger’s Post was spot on. Burn super hot into storage then remove what’s needed for the heating load.
In short, the modulation occurs with your pump and mixing controls. Not at the boiler itself.
It’s not like thinking of a hi tech gas boiler. My LP boiler is set up to be “dumb”. My radiant controls take care of all modulation and I don’t try modulating the few rooms that have HWBB.

What do you expect your budget to be?
I'm not doubting your advice or questioning anyone's experience but why do some manufacturers market their boilers as able to modulate from 100% down to 30% or less? Vigas is one. Am I wrong to believe their claims?

My budget is on the low side due to some other related projects. For the boiler only I would like to find something in the 2-5k range. That may not be realistic.
 
Some can modulate but I dont think that will prevent lighting a fire every day.

You will likely need a bigger budget unless you happen on a good used deal. Have you looked in the classified section?
 
For 5k you might be able to get a new eko 25 and the parts needed to get it done. Assuming you already have a chimney to use and can do the install yourself. And no storage... a very basic install.

If you can accept large temp swings in the house it will work and be somewhat efficient. Just shut off the oil/propane boiler and load the gasser when you can and get the house as warm as possible until the next time you can load.

Just make sure you have dry wood. Cut split and stacked for over a year. Or don’t bother trying.
 
For 5k you might be able to get a new eko 25 and the parts needed to get it done. Assuming you already have a chimney to use and can do the install yourself. And no storage... a very basic install.

If you can accept large temp swings in the house it will work and be somewhat efficient. Just shut off the oil/propane boiler and load the gasser when you can and get the house as warm as possible until the next time you can load.

Just make sure you have dry wood. Cut split and stacked for over a year. Or don’t bother trying.

I have been eyeing those Ekos as one option. Any suggestions on where to purchase?

A new ss chimney in a better location is one of those 'other projects'.

Im in the process of tracking down some propane tanks for pressurized storage.

I was planning to install myself, with lots of advice from the pros here.
The 2-5,000 was only for the boiler itself.

I already cut my wood a year ahead. I ordered a moisture meter yesterday, just to see what my current wood is.

Got to leave for church soon, it's my turn to preach this morning!
 
I have been eyeing those Ekos as one option. Any suggestions on where to purchase?

A new ss chimney in a better location is one of those 'other projects'.

Im in the process of tracking down some propane tanks for pressurized storage.

I was planning to install myself, with lots of advice from the pros here.
The 2-5,000 was only for the boiler itself.

I already cut my wood a year ahead. I ordered a moisture meter yesterday, just to see what my current wood is.

Got to leave for church soon, it's my turn to preach this morning!

The US supplier for EKO is newhorizonstore.com. Zenon also carries Attack which I would look at as well- I like the inducer draft set up on the Attack vs the forced draft set up on the EKO. IMHO you will see less smoke out the loading door on reloads on a induced draft set up especially if you don't have a lot of chimney height.

As far as storage, call you local propane suppliers and ask if they have any scrap tanks, rusty on the outside, missing tags, etc. I found 2 x500g tanks from my local coop for $200 each. Only down side to scrap tanks is they will have to be cleaned really well on the inside.
 
Check the classifieds, I bought my system used and saved a ton of money. Taxidermist had a eko 60 and 2 500 gallon tanks that he was selling pretty cheap that might still be available. Skimming through craigslist the other day there was a pretty clean looking eko 60 for $900.00. There is no reason to spend big money on these systems
 
A new ss chimney in a better location is one of those 'other projects'
Supervent class A chimney is available at Menards and will hands down be the cheapest price you'll find on one (especially if you buy during a 11% off sale) I have put several of these up over the years for myself and family members and they work well.
 
Hi all. I'm new to the forum here, but have been casually (obsessively according to my sweet wife) reading up on these indoor gasifiers. Im 29 and have lifelong experience burning wood, but have just recently been made aware of a (not so) new way of doing it: the indoor boiler with storage! I'm almost convinced. I was planning to install an OWB this summer until I realized:
#1 most used units were nearly worn out and cheap or nearly new and costly.
#2 new units (even non EPA which can still be bought) were very expensive
#3 all are rather inefficient.

Im currently leaning toward the indoor boiler with storage. My first question is one I haven't seen asked yet. When you only do a 3 to 6 hr batch burn to reheat storage, does the fire go out completely? I don't like the thought of always relighting. I would much rather keep a smaller fire going all day like I do now with a EPA wood stove. Is that possible using a modulating boiler?

This is getting too long, so I'll stop for now. Any comments?
I would agree with the others here, starting a fire will be a non-issue for you (with the right boiler and dry wood). Regarding what boiler to get, I suggest you take a step back and really look at the total cost of this project ($'s + effort). Based on my experience you will deeply regret making the boiler decision solely on cost rather than what you would like out of the system - especially if you are giving thought to low temp emitters, leveraging outdoor reset, etc. I would 2nd the person that advised you to contact Chris at Tarm. They always have some amazing deals kicking around and they carry a line of boilers (Effecta) that is at a lower price point than the Froling but has amazingly functionality - especially if you are looking for a plug and play that a significant other can handle if you are away.