I recently purchased and am installing a Tarm OT-50. This boiler is a little big for my house so i plan on having to build smaller fires and tend it often. The other option is to burn it low and worry about creating creosote. I have heard that using thermal storage it a big help with these boilers. Currently i am low on money, but for the right price i might consider getting a thermal storage tank. Can anyone suggest a place where i can get a thermal storage tank at a reasonable price. I'm looking for something under 1000 gallons as i only have a bulkhead to my basement and have to be able to fit it through a doorway. I had heard that there were places selling storage tanks in the $1000 to $2000 range, but i have not been able to find anything near that price. Can anyone offer some help please?
Economical thermal storage tank
- Thread starter Carl Webber
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woodsmaster
Minister of Fire
Smaller propane tank or air compressor tanks. Take to fab shop and have fittings u need welded on if they don't have ones that will work for you. Do some research on here. Lots of info.
cityboy172
Feeling the Heat
maple1
Minister of Fire
Check local large scrap yards for used propane tanks.
EDIT: And storage would absolutely improve your boiler performance. Especially if it is oversized. It would reduce wood consumption, and creosote related maintenance.
EDIT: And storage would absolutely improve your boiler performance. Especially if it is oversized. It would reduce wood consumption, and creosote related maintenance.
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NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
I understand that i can use these, but what i don't understand is how. From what i have seen, the thermal storage tanks have a heat exchanger in them so the boiler water doesn't mix with the water in the tanks, it just warms the water in the tanks and then goes back to the boiler. Am i thinking of this wrong? When you set up thermal storage tanks for a boiler do you simply put them in a loop with the boiler so it is all the same water and heats as the boiler heats? Do you need a circulator to keep keep the water flowing from the boiler to the tanks and back again? If i were able to find 5 of these old 200 gallon propane tanks and set them up, would i set them ups as bank all connected and then put all the zone circulators after them? Can someone give me a link or post a schematic so i can better understand this.
NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
most manufacturers have basic design and scenarios in there manuals that are online. tarm,etc
woodsmaster
Minister of Fire
No heat exchanger needed if you do pressurized storage. the water in the tanks is the same as what runs threw the boiler. You could also do open storage where you build a wood box put a rubber liner in it and a heat exchanger. More than one way to skin a cat. Depends on , tanks available, regulations ( you may need certified tanks for insurance if pressurized ) and what fits your needs and space. Pressurized is the way to go if possible for you. Again, do some searches and research on this site. All the info is already here at your fingertips.
Chris Hoskin
TarmSalesGuy
jump on this Carl. Also see our plumbing schematic "Automix-Single Tank" for set up.
NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
Check your dimensions. don't think it will fit through a standard doorway. its a good deal!
maple1
Minister of Fire
Depends on if open unpressurized, or closed pressurized.
And that may come down to what you can fit into where you want it.
The next question i have is, how do i run the boiler when it is hooked up to storage. I have heard tons of people saying they run these old boilers once a day and run the rest of the time on the heat stored in the storage tank. My boiler specifically says not to run it as a cold start boiler because the moisture that collects on the inside of the boiler will mix with flue gasses when you start it back up and will corrode the metal. How are people doing this without destroying their boiler? I haven't seen this explained anywhere, i just see people saying they do it. From what you guys said earlier the pressurized system is the same water as what is in the boiler, so it would make sense to me that as long as the storage is hot, the boiler would be hot, even if there wasn't a fire in it. So, unless i'm missing something, it sounds to me like pressurized storage is the way to go for me since i have an old Tarm boiler.
maple1
Minister of Fire
My boiler is only burning between 6 and 10-12 hours a day in the winter. That's the way it was intended to be run, and I don't think it has special construction inside.
Realistically, the boiler won't go all that cold burning like that in the winter - bottom of my storage is usually around 120 at least when I start a burn, the boiler not a whole lot colder. And I don't think much moisture would collect on the inside of the boiler in that amount of time.
One thing I don't think was mentioned above, is that if you do add storage, you will also want to add a thermostatic return protection valve that will keep the return water above 140° (Danfoss is a common one). Very important. Having extended periods of cold return water entering the boiler when it's burning would definitely not be good.
Realistically, the boiler won't go all that cold burning like that in the winter - bottom of my storage is usually around 120 at least when I start a burn, the boiler not a whole lot colder. And I don't think much moisture would collect on the inside of the boiler in that amount of time.
One thing I don't think was mentioned above, is that if you do add storage, you will also want to add a thermostatic return protection valve that will keep the return water above 140° (Danfoss is a common one). Very important. Having extended periods of cold return water entering the boiler when it's burning would definitely not be good.
That is some good info. I will check that out. I was just doing some calculations and i'm running into some problems that I'm sure most people have seen. My basement door behind the bulkhead is 34 inches wide so that limits the size of tank i can bring in. The height limit in the basement is roughly 7 feet because of piping and other stuff. After taking some measurements, and doing some calculations, a tank that is 34 inches wide and 7 feet tall is roughly only 40 gallons. I think i could possibly fit maybe 2 of these in my basement with everything else that is down there and the wood i need. Is it worth it to do to all the trouble for only 8 gallons of storage? Most people i have read about are talking about anywhere from 400 to 800 gallons of storage. It looks to me like i can't get anywhere near that using pressurized storage. Is 80 gallons of pressurized storage enough to make a difference in my boiler efficiency? I have a Tarm OT-50 and according to the spec sheet it holds 91 gallons of water. So, total that would be something like 170 gallons of water. That doesn't sound like enough to me but i could be wrong.
NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
I would search for 250 gallon propane tanks. Smokeless heat has them set up on their web site vertical and stacked configurations.Ideally most with new units are running 500-1000 gallons. so if it where me I would set up as if you had a new boiler, since you most likely will replace at some point and the work will be done. IMHO
PM me and I can get you a salvage yard number.
PM me and I can get you a salvage yard number.
maple1
Minister of Fire
a tank that is 34 inches wide and 7 feet tall is roughly only 40 gallons
I came up with something closer to 300 gallons for 36"dia x 7' tall. Doesn't take into account the cylindrical end though. I know my '330s' are 3' x 9'.
I came up with something closer to 300 gallons for 36"dia x 7' tall. Doesn't take into account the cylindrical end though. I know my '330s' are 3' x 9'.
NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
yeah, i figured that out after. My math was way off. i think instead of calculating the volume of a cylinder i was calculation the surface area. So, after figuring that out, it sounds like if i could get my hands on 2 old propane tanks i could do OK. I could try for two of the 8 foot ones, but even two of the upright ones are something like 200 gallons so together i would have 400 gallons of storage. If i'm going to turn them into storage tanks for my boiler is there anything special i need to know? should i be all set as long as they are not too rusty? Should i pressure test them to the same PSI as my boiler (72 psi)? When i add fittings do they need to be welded in any special way or can i just have someone with a welder just slap some fittings on them? Should i have one fitting at the top and one at the bottom, or both at the top or bottom? should i go with larger fittings or like 1/14 inch so the output on my boiler will match, or with smaller like 3/4 inch? Do i only need two fittings, one for in and one for out, or should i add extra ones for other things like a pressure and temp gauge?
NE WOOD BURNER
Minister of Fire
- Dec 30, 2012
- 754
http://www.smokelessheat.com/thermal-storage-tanks/250-gallon-propane-tank-with-ports
FYI This is what these guys do.
FYI This is what these guys do.
woodsmaster
Minister of Fire
Id go with 1 1/4 " fittings on the tank. weldolets are the best option to use as fittings but, nipples could also be welded on. One fitting on the very top and one on at the very bottom. I would also put a spot for a thermowell near the top, bottom, and middle for temp gauges but that isn't a must have. Try to find tanks without deep pitting but some minor pitting should be okay. Yes pressure test after the welds are done. Be sure to clean the tanks out good with some bleach water. I filled mine with water to make sure where was no gas left in the tanks. shouldn't need a pressure gauge on the tanks, It will be the same pressure as the boiler.
maple1
Minister of Fire
Make sure you have a competent welder - preferably one who regularly does pressurized stuff. It's easy to stick metal together, but getting air and water tight under pressure is a bit more. Mine was done by a pro but even he had to come back & fix up a couple pinholes. That was mostly my fault for accidentally picking cast fittings out of the supply bin (supplier mixes them I guess). So also make sure to avoid cast fittings - hard to tell the difference at times. And pressure test before he leaves. Don't think 72psi is necessary, think I pumped mine to 30. And also based on that experience, I wouldn't do any more fittings than I absolutely have to. See what fittings are there already, and make the best use of them you can. I would avoid thermowells, external temp probes and strap on aquastats seem to do just as well with no leak risk.
I just pressure washed mine, but even then got very little dirt out. Maybe I got lucky with how clean they were - I don't think I had to do anything. They did stink, but I couldn't get them to light off no matter how hard I tried.
I just pressure washed mine, but even then got very little dirt out. Maybe I got lucky with how clean they were - I don't think I had to do anything. They did stink, but I couldn't get them to light off no matter how hard I tried.
after checking things out, it appears like the best i'm going to do for storage in my basement is 3 120 gallon tanks for a total of 360 gallons of storage. I don't think i'm going to have room for any more. I could be wrong but i haven't found any tanks that are larger than 120 gallons that would fit correctly in my basement. I'm going to call a scrap yard at some point and see what they have. Maybe i'll get a surprise and find something that is exactly what i need. Assuming that i can't find anything else, is 360 gallons of storage enough to accomplish anything? If i started the storage out at 200 degrees and ran it till it was at 140 degrees that is a 60 degree drop. That would give me about 173,000 btu of storage. If i calculated right, my house at best uses about 67,000 btu an hour to stay heated in winter. That means i would need to fire the boiler about once every 3 hours to keep the house warm. Does all this sound ok? or do i really need to figure out how to get more storage to make it worth my time and effort?
maple1
Minister of Fire
We are in a 20 year old 2700 sq.ft. two storey (plus unfinished unheated basement) on an exposed windy hilltop.
My usual winter routine is make a fire on late afternoon, and burn it until I go to bed. Which amounts to about 6 hours or so of burning. On the very coldest of days, I will make the fire earlier - but no earlier than noon. And maybe throw a bit more wood in on the way to bed. So that's 10-12 hours of burning, at the very most, and that amounts to maybe only 20% of the time? Wild guess.
We have programmable thermostats, that depending on the zone set back a degree around midnight, another degree at 6am, then bump back up the two degrees at supper time. That's bedroom zones. The kitchen area setsback a couple degrees around 10pm, bumps up for a couple hours around 6am, then bumps back up late afternoon. The other zone is living room/office, and manual stat. I turn it down a bit on the way to bed, then back up when I get up. The result of doing all that, is that I'm burning when the heat demand is the most, and coasting on storage when it is the least. So you can regulate some things to jive your heat load with your burning routine.
Have you checked out open storage tanks? Tom in Maine (forum member) sells them, they are quite popular for tight spaces. Boxes you put together, then put a liner in. You would then need heat exchager(s), but expansion tanks would be less of an issue.
My usual winter routine is make a fire on late afternoon, and burn it until I go to bed. Which amounts to about 6 hours or so of burning. On the very coldest of days, I will make the fire earlier - but no earlier than noon. And maybe throw a bit more wood in on the way to bed. So that's 10-12 hours of burning, at the very most, and that amounts to maybe only 20% of the time? Wild guess.
We have programmable thermostats, that depending on the zone set back a degree around midnight, another degree at 6am, then bump back up the two degrees at supper time. That's bedroom zones. The kitchen area setsback a couple degrees around 10pm, bumps up for a couple hours around 6am, then bumps back up late afternoon. The other zone is living room/office, and manual stat. I turn it down a bit on the way to bed, then back up when I get up. The result of doing all that, is that I'm burning when the heat demand is the most, and coasting on storage when it is the least. So you can regulate some things to jive your heat load with your burning routine.
Have you checked out open storage tanks? Tom in Maine (forum member) sells them, they are quite popular for tight spaces. Boxes you put together, then put a liner in. You would then need heat exchager(s), but expansion tanks would be less of an issue.
My big problem right now is money. Unless he sells his storage tanks for something like $500 its going to be too much for my budget. Although it is something i'm considering for the future. I've seen collapsible storage tanks that are 500 gallons that have a relatively small footprint but they are expensive. I'm short on money, but i can't really afford to heat the house on oil anymore as it is costing me $4000 a year. i'm stuck between a rock and a hard place. So, for now i'm just trying to get the system in as cheaply as i can, but do as much as i can. It makes sense to me to have storage, my big problem is money. It seems to me like the cheapest option for me is to go with the used propane tanks, as long as they will work for me and are adequate. At this point, everything i'm getting for this system is used and either through people i know or through craigslist. Once i have the system in and working and it is saving me money i can work on trying to upgrade the different parts of the system as i go. I'll check out Tom in Maine and see what he sells the tanks for just to be sure i can't do it. I would hate to assume and not at least check it out.
As it is, my house is roughly 28 years old, it is 2000 sq. ft. and two stories. I am currently running a weil mclain oil boiler that has a 100k btu net output. The boiler also provides my hot water. During the winter months I am using about $500 of oil a month. that is for about 6 months of the year. then for the other six months i use between $500-$700 for the whole six months. During the winter months its not too bad in the house, the boiler will keep the house around 70. When it gets cold out, 10 drgrees or below the boiler has a hard time keeping up. The boiler will run all the time and the thermostat will only maintain 68. The boiler i am putting in has an output of 140k btu on the wood side, so it should be able to handle my house. I'm also considering the idea that i might need more baseboard in the house.
As it is, my house is roughly 28 years old, it is 2000 sq. ft. and two stories. I am currently running a weil mclain oil boiler that has a 100k btu net output. The boiler also provides my hot water. During the winter months I am using about $500 of oil a month. that is for about 6 months of the year. then for the other six months i use between $500-$700 for the whole six months. During the winter months its not too bad in the house, the boiler will keep the house around 70. When it gets cold out, 10 drgrees or below the boiler has a hard time keeping up. The boiler will run all the time and the thermostat will only maintain 68. The boiler i am putting in has an output of 140k btu on the wood side, so it should be able to handle my house. I'm also considering the idea that i might need more baseboard in the house.
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