I am still going around and around between an EKO 25 and a Tarm Solo Plus 30 for the new house I am building. Either way, I am interested in storage. Where can I purchase a large storage vessel? Also, If I heat my hot water with a direct coil in this resevoir, what are good options for backup hot water? We will often be away for the weekend, and I am considering a direct vent propane boiler as backup. What is a good way to supply backup hot water? I would not want the propane unit heating the resevoir. I may not purchase the backup unit at this time. My hope is that I could keep the house at 50 degrees for a few days on the resevoir when we are away. I intend to do all of the installation myself. I liked the specs on the Econoburn unit, but they won't even give me a quote since I am not a licensed contractor. This will all be quite a challenge...I see the most difficult part being the lack of a parts supplier in my driveway...there are a lot of little pieces to plan for.
Who manufactures water storage tanks for wood boiler
- Thread starter tuolumne
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
- Status
Eric Johnson
Mod Emeritus
Here's a thread with some Econoburn pricing mentioned on the last page.
https://www.hearth.com/econtent/index.php/forums/viewthread/11467/P15/
For EKO pricing, the best I've found is here:
http://www.cozyheat.net
Tarm is probably somewhere between the two.
There's a company called SST, I believe, that sells tanks and heat exchangers for wood-fired boilers. They're the ones you get through Tarm USA. Most people who have actually bought storage tanks seem to wish they had gone the DIY route. There are a few threads around here on that topic as well.
Glad to hear you're planning on a wood gasifier.
https://www.hearth.com/econtent/index.php/forums/viewthread/11467/P15/
For EKO pricing, the best I've found is here:
http://www.cozyheat.net
Tarm is probably somewhere between the two.
There's a company called SST, I believe, that sells tanks and heat exchangers for wood-fired boilers. They're the ones you get through Tarm USA. Most people who have actually bought storage tanks seem to wish they had gone the DIY route. There are a few threads around here on that topic as well.
Glad to hear you're planning on a wood gasifier.
BrownianHeatingTech
Minister of Fire
I'm looking for a good supplier for tanks, as well. I'm sick of companies that don't feel the need to return calls.
Anyway, to answer your question about backup hot water, if you are already using propane, buy a Noritz tankless water heater. They are rated for up to 120-degree inlet water, so you just hook the outlet of your tank's domestic coil to a mixing valve set for 120 (or lower, if you like), and then to the Noritz inlet. Whenever the tank is making water hotter than the setting on the heater, the heater simply won't fire. If the tank is only raising the temp to 80, the heater will run, but not as hard.
Joe
Anyway, to answer your question about backup hot water, if you are already using propane, buy a Noritz tankless water heater. They are rated for up to 120-degree inlet water, so you just hook the outlet of your tank's domestic coil to a mixing valve set for 120 (or lower, if you like), and then to the Noritz inlet. Whenever the tank is making water hotter than the setting on the heater, the heater simply won't fire. If the tank is only raising the temp to 80, the heater will run, but not as hard.
Joe
BrownianHeatingTech
Minister of Fire
Tarmsolo60
Feeling the Heat
NTI makes a nice direct vent NG/LP gas boiler for your backup heat and you can get the combi model which will also give you backup hot water without heating your storage tank. I've installed about a dozen of the units (no combis yet because the houses I so usually want indirect storage). They and are very efficient and are a compact unit that hangs on the wall.
BrownianHeatingTech
Minister of Fire
Tarmsolo60 said:
I concur about the Trinity Combi units, as well... https://www.hearth.com/econtent/index.php/forums/viewthread/11562/
Joe
That's a nice looking install Joe. Those are all the fittings I wish I had in a truck parked outside. What is the cost of the trinity unit? What did that install cost (ballpark) for materials (not the baseboard/radiant distribution, just stuff in the basement). I will have mostly radiant wall panels, radiant in warmboard for a 400 sf school room, and radiant in some kind of track overlay for the kitchen.
BrownianHeatingTech
Minister of Fire
tuolumne said:
The heat is actually a pair of air handlers, replacing two propane furnaces. One also includes a 16-SEER A/C system. Which all boils down to not being able to compare apples to apples, as the job included a lot more than just the two boilers.
I also can't really comment on the pricing of the Trinity, as local prices can vary.
Joe
I looked at buying a tank and found that building one out of wood is more practical and many people have done it. Mine is almost done, it will have an EPDM liner and it is made of pressure treated 2X4s and 3/4" plywood and a lot of screws. It will be 6X6X4 and should hold about 700 gallons, will be using 2" foam insulation on the inside of the tank and then put the liner over that.
Steve
Steve
Nofossil
Moderator Emeritus
For tanks, you have three choices:
1) A kit that's essentially an above-ground pool
2) Build your own
3) Buy a pre-made tank locally
Option 1 is probably the easiest. Option 2 is perhaps the least expensive, with some risk of failure depending on your design skills and available materials. Both these choices will be open top unpressurized tanks.
Option 3 has two sub-options - pressurized and non-pressurized. Some folks are using 500 gallon propane tanks.
Pressurized tanks are simpler in that they don't require an internal heat exchanger. They do require a large expansion tank (40 to 80 gallons). Make friends with your local scrap dealers - there may be bargains to be had. I got an open-top 880 gallon stainless tank for $400.
1) A kit that's essentially an above-ground pool
2) Build your own
3) Buy a pre-made tank locally
Option 1 is probably the easiest. Option 2 is perhaps the least expensive, with some risk of failure depending on your design skills and available materials. Both these choices will be open top unpressurized tanks.
Option 3 has two sub-options - pressurized and non-pressurized. Some folks are using 500 gallon propane tanks.
Pressurized tanks are simpler in that they don't require an internal heat exchanger. They do require a large expansion tank (40 to 80 gallons). Make friends with your local scrap dealers - there may be bargains to be had. I got an open-top 880 gallon stainless tank for $400.
Where can I learn more about the pressurized option. I assume this means the tank is just a very big section of pipe in the main loop. Are there any stratification issues? A very large part of the expense in the tank quote from Tarm was the heat exchanchers. Since I cannot get inside something like a propane tank, that would mean an indirect HWH?
Eric Johnson
Mod Emeritus
An indirect is one good option. A cheaper alternative would be something like a sidearm heat exchanger connected to a conventional electric, gas or oil hot water heater. You pump hot water through the outer jacket, and domestic water convects through the inner tube and heats the water in your tank. Here's a picture of mine. Even at today's copper prices, you can build one yourself for around $100. It may not be the most efficient rig in the world, but it sure produces a lot of free hot water. Note that I have the flow going the wrong way in the diagram. Boiler water should flow from top to bottom so that it counterflows.
Attachments
Eric,
I have my sidearm plumbed just like your diagram shows and asked Dave from cozyheat if that was the way to do it. He told me you want your boiler supply coming in the bottom because the cold water chases the hot up to the return causing the thermal siphon. Mine works and so does yours so which is the correct way?
I have my sidearm plumbed just like your diagram shows and asked Dave from cozyheat if that was the way to do it. He told me you want your boiler supply coming in the bottom because the cold water chases the hot up to the return causing the thermal siphon. Mine works and so does yours so which is the correct way?
Eric Johnson
Mod Emeritus
To be honest, I had it piped the way you describe with my previous boiler, and it worked just fine. Sometimes this stuff is academic, with no appreciable practical difference.
As I understand it, heat exchangers are supposed to counter flow, so that the water being heated is moving in the opposite direction of the water doing the heating. Since the water heater water needs to rise, that would dictate flowing the boiler water in the opposite direction. A friend of mine, carpniels, explained it to me another way that perhaps makes even more sense. He said that the water returning to the water heater should be encountering the hottest water from the boiler side as it's going into the top of the hot water heater. Makes sense when you think about it.
That's a funny story about Dave. When I first sent him my preliminary piping diagram, I had the hx piped like it is in the diagram. He made some changes to my schematic, including making the water flow in the opposite direction. So maybe it depends on the day of the week or the phase of the moon. I don't think it matters that much on this scale. Maybe if you're designing a power plant.
As I understand it, heat exchangers are supposed to counter flow, so that the water being heated is moving in the opposite direction of the water doing the heating. Since the water heater water needs to rise, that would dictate flowing the boiler water in the opposite direction. A friend of mine, carpniels, explained it to me another way that perhaps makes even more sense. He said that the water returning to the water heater should be encountering the hottest water from the boiler side as it's going into the top of the hot water heater. Makes sense when you think about it.
That's a funny story about Dave. When I first sent him my preliminary piping diagram, I had the hx piped like it is in the diagram. He made some changes to my schematic, including making the water flow in the opposite direction. So maybe it depends on the day of the week or the phase of the moon. I don't think it matters that much on this scale. Maybe if you're designing a power plant.
Nofossil
Moderator Emeritus
tuolumne said:
That's one way to do it. You can also have multiple external heat exchangers so that the water in the tank is isolated. The sidearm is an example, but people also use flat plate and other designs. Counterflow would be more important when there's not as much temp differential to play with - if you had solar panels that worked via thermosiphon, for instance.
Eric Johnson
Mod Emeritus
The nice thing about sidearms is that gravity powers the domestic water side, and they're cheap. With a flat plate or a conventional shell & tube, you have to pump both sides. That means an expensive bronze circulator on the DHW side.
Obviously, an in-tank coil or other hx is the most efficient solution for DHW: No heat loss from the hx and you only need to pump one side. But pricey.
Obviously, an in-tank coil or other hx is the most efficient solution for DHW: No heat loss from the hx and you only need to pump one side. But pricey.
Eric Johnson said:
I just went back through my emails from Dave and I was wrong he did say to run it into the top, I was talking with a master plumber whom I bought my pex from and he was the one who told me to run the boiler supply into the bottom. I wonder if I would benefit at all by changing it, I have a 40 gallon water heater and after about 2-3 showers in the morning I do run out of hot water and it takes a bit to get it back. Just when I thought my install was complete :-S
BrownianHeatingTech
Minister of Fire
Eric Johnson said:
Technically, an external plate heat exchanger provides much better performance than an in-tank coil. Not because of the inherent design, but because the actual indirects available on the market have undersized coils. Looking at some of the European tanks that are sold over there, our tanks often have 1/3 the heat exchanger that theirs do. The notion that we might want to shrink the tank by having better recovery - or keep it the same size and use lower-temp boiler water to heat it - doesn't seem to occur to manufacturers here... we're a small segment of the market, unfortunately.
Joe
- Status
Similar threads
