Some wood boiler questions - Tarm vs. Econoburn, & storage

[wombosi]

Hi all,

Just beginning to understand the world of gasification boilers.

I have a few good options for used units near me - which makes this idea affordable.

A Tarm Solo 30 Plus MKII - with 600 gallon storage tank.
This unit is from 2008.

An Econoburn EBW 150 from 2012 in near mint shape, only used as a backup to oil sporadically, but no tank.

I don't quite fully understand how the storage tanks work relative to the amount of wood used, how long they stay hot, how much energy savings there is, etc... Must do a number on the water bill, no?

Both of these are comparably priced, so which one would I be better off with?

Thanks!

 

[peakbagger]

You have a steep learning curve. The basic concept behind storage is that wood burns the most efficiently at full bore. The hotter the better. The goal of storage is allow the boiler to run at full bore for a long period of time at maximum efficiency. The storage then stores the heat until you need it. If done right you may only have to run the boiler every 24 hours in the coldest weather. If you buy the Econoburn, you will need to buy storage. Dont waste your time just putting in a wood boiler without storage. As for the one versus the other I expect there are fans of either. If you want everything you want to know about biomass heating go to this link and spend a couple of days watching the course https://www.heatspring.com/courses/...iciency-biomass-boilers-sponsored-by-nyserda/ Its free and taught by the best teacher I have found.

 

[maple1]

The only thing related to a water bill, is whatever the water would cost to fill them up. Which shouldn't be much - should it? No water meters here, so don't really know.

They allow the boiler to burn wide open until the fuel is gone. And wide open is how a gasifying boiler works and burns the best and most efficiently. Starting & stopping a fire (or trying to) means idling & smoldering and making smoke & creosote in between the wide open periods. Once the burn is done, they stay hot until your house uses the available heat they store - which is dependent on how hot you charge them , how big they are, and what your heat load is. At which point, you light a fire again.

I think the Tarm is induced draft, and the EB is forced? Based on that I would lean Tarm, but don't know what kind of install you have in mind. Quite sure I would not put an EB inside my house. As far as I know though, EBs are very ruggedly built, but seem to remember not the easiest to clean. So I would also research and not underestimate ease of cleaning - it's becomes a very important factor once you start living with it.

 

[wombosi]

Thank you both for the insight.

How do I go about calculating the size of storage tank? Any thoughts about pressurized vs. open top?
I could very easily build the open top and am learning to weld so could probably modify an old propane tank as well.

My house is about 1800 square feet. New windows. Spray foam insulation throughout.

 

[JohnDolz]

I would agree that storage is a must. When I was considering what I wanted to install I put storage as my top priority, figuring storage was forever, a boiler could be replaced.

Others will give you the technical reasons, I'll take a shot at what I consider the highlights:

* how much storage:
* More is better
* You need an adequate amount to support your boilers output
* 600 gallons should be adequate for the house you described
* I prefer pressurized, I think it is simpler
* definitely agree with reading the link peakbagger sent you
* without even knowing what you are paying for the used equipment I would guesstimate your total project cost to be 2x the purchase price you are considering

Skied at Butternut for several years, drive is under an hour - happy to have you stop by and poke around.

Good luck!

 

[wombosi]

Skied at Butternut for several years, drive is under an hour - happy to have you stop by and poke around.

That's awesome man! Thanks for the invite and I may very well take you up on that.

 

[peakbagger]

If watch the biomass course you will know how to calculate a tank size and lot of other details on how to properly pipe up the system. There are some very important safety systems you need to understand how they work and to integrate them into your design. There is also a system to reduce dew point corrosion and creosote in the boiler that is important. If you buy a used boiler that is being taken out and replaced with some other heating fuel you will hopefully get these components with it otherwise you will need to budget for normally open valve to dump heat into either a house zone or a dedicated heat dump loop. You will also need a three way valve configured to route cold boiler water on startup directly back to the boiler until the boiler heats up, As the water heats up, the valve slowly open to allow water to the rest of the system while keeping the return water hot. If you dont do this you can run the boiler jacket too cold and possibly create extended periods corrosion in the boiler and possible creosote. If you dont get all the valves and pumps you may need to spend $1000 to buy all the extras you need (not including the tank)

Storage volume is tied to what type of heat emitters you have. A radiant heating system designed for low temps can get away with a smaller tank but someone with slant fin baseboard would do well with far bigger tank. Start at 500 gallons and go up as you can afford.

A wood boiler really needs to be part of overall system and it usually needs to be designed to tie into an existing heating system. That requires it to be designed right. There is a lot of water in the system and if you get it wrong you can have a few floods.

 

[airlina]

here is a picture of my econoburn in action and the elements you can expect in a storage system. mine is a 500 gallon repurposed propane tank.

 

[salecker]

I have an Econoburn.
1 or 12 years old.I would not hesitate to buy another one.
Mine is easy to clean now.The worst thing used to be getting the turbulators out.I now have a rope and pully system so it takes all of 5 min to get it apart to clean the tubes. I made a tube cleaning tool that works better that anything else i found.If i am not disturbed the tube cleaning takes about 1 1/2 hours.
Personally i would not have a fire source inside my house. I thank myself every time i go to my boiler room for having the heating system in a seperate building.