thermal storage idea for my homemade boiler and system

[cumminstinkerer]

Would anyone out there have any good reason why I couldn't use a retired anhydrous ammonia 1000 gallon nurse tank for non pressurized storage. I think I can pick one up for scrap price. I may have to split it in the middle and weld a plate on each new end to make it fit where I want it but that would not be to challenging.

 

[spyder62]

It’s some nasty stuff

 

[cumminstinkerer]

It is but if treated with respect perfectly safe, these tanks have been evacuated for a few years and I have dealt with the stuff my whole life having grown up helping with the farm.

 

[cantoo]

A few guys around here have used propane tanks. I have my eye on one but just haven't had the time to get it yet.

 

[Guswhit]

I am in the middle of hooking up 2 500 gal used propane tanks for my storage as we speak. I didn't have room for the 1000 gal in length, I'm stacking the 500's. Anyway, I'm down toward the end, but I'm still trying to figure out some of the electronics to shut everything down after the batch burns. I think I should be using a lot less wood and better combustion burning full open with storage.
Anyway, make sure you weld in some extra ports so you can monitor water temp in various locations and an extra set of outlet/inlet ports for future expansion. You may never need them, but it's a lot cheaper now! I'm planning on spray foaming mine after checking for leaks and checking my water P.H.

 

[NSMaple1]

External temp sensors work pretty good without needing to weld more ports in.

 

[Guswhit]

External temp sensors work pretty good without needing to weld more ports in.

Yes they do, but 1 of my buddies did that, spray foamed over them and 2 years later sensor went bad. If you use ports, you can just unscrew them, not try and search under insulation for them. Of course if you use other insulation, its not really a problem either.
Are you planning on batch burning and using the stored heat off the tanks?

 

[Guswhit]

I see you are on another forum I lurk on asking similar questions, and that you do intend to batch burn. My issue right now is figuring out how to shut the main circulator pump and blower fan off when the burn is complete. I have looked at what some other guys are doing, monitoring tank temps, weighing wood to figure out how large a fire to burn completely, full out to raise supply tanks to high enough temperature to last for extended periods, however, I am confused on the electronics to get them to shut off when the fire has burned out. How are you planning on achieving this?

 

[cumminstinkerer]

@Guswhit Pm sent I havent got it together yet going to work on it tonight after work, but essentially I will monitor flue temp and include an override for starup purposes. even if I overshoot tank temp and go to idle it should still go into shut down and not be able to come back on unless I activate the manual override, right now I only have about 325 gallon plus whats in the boiler in the system and my circ runs full time, one fire a day has been handling DHW and the little heat we have needed, if I would just add the second circ and shut down the boiler from the loop when not firing I am certain my charge would last even longer. I am still waiting to back about the anhydrous tank, Hoping to get that all together before it decides to get real cold, not that this morning was too nice.

 

[kljahnz]

you'll be fine, it is done alot.

 

[rancher2]

Cumminstinkerer
I have a Garn so I already had 2,000 gallon storage. I added a another 3,000 gallon stainless milk tank from a twin screw truck that a Coop had used for water spray tender for years and then the truck got wrecked. It was cheap and already foamed insulated. I just use a Ranco thermostat to turn the pump on and off between the Garn and extra storage tank. I run heat exchanger's on my loads and have thermostats and relays that run my pumps and blowers in my furnaces . Mine is set up that the pumps only run when there is a call for heat. I burn year around domestic water in the summer. I only have to burn the Garn about every two weeks in the summer with that much storage.

 

[NSMaple1]

Holy crap - I don't think I've seen anyone with that much storage. That is huge. You must be heating big area? I only have 660 in my tanks and would really love more. How often do you burn in the winter? Those Garns really pump the heat, that's for sure.

 

[cumminstinkerer]

@rancher2 thats crazy, I am trying to run year round as well, my system only has about 500 gallon total right now, I dont think at this stage I will get the tank ready before cold weather, but I do have an extra 275 fuel oil tank in the basement already that I think with a little modification will work for this year, will still have to redo plumbing, I currently have one 275 gal fuel tank and an old 50 gal DHW tank in the system for experimenting, that is how I managed to get 500 gal. I think for this year I am going to add the other tank in and do a plumbing design similar to the image I am attaching The note book paper drawing is what I plan to go to and the paint drawing is how the setup is currently.

 

[Guswhit]

Cumminstinkerer
I have a Garn so I already had 2,000 gallon storage. I added a another 3,000 gallon stainless milk tank from a twin screw truck that a Coop had used for water spray tender for years and then the truck got wrecked. It was cheap and already foamed insulated. I just use a Ranco thermostat to turn the pump on and off between the Garn and extra storage tank. I run heat exchanger's on my loads and have thermostats and relays that run my pumps and blowers in my furnaces . Mine is set up that the pumps only run when there is a call for heat. I burn year around domestic water in the summer. I only have to burn the Garn about every two weeks in the summer with that much storage.

Do you think that thermostat would work to shut off a pump and a blower fan hooked together? I have a portage and main that I am going to hook up with storage to try and batch burn with 1000 gal of storage, plus the burner, should have about 1250 gallon then. Trying to figure best way to make this a batch burner like a garn so it shuts down when temp is met and not start again. I received some tips from a couple of guys, but haven't seen a wiring diagram and can't quite wrap my head around it. Some are talking about a stack sensor to shut it down with a manual override when you want to start a new fire, but I haven't seen how this gets done. Still working on my tanks, just about ready to get them set and plumbed into system. so wiring will be next.

 

[Guswhit]

1 more question for you guys running storage tanks. Are you all running them through an exchanger to heat the tanks or are you using a separate circulator that flows through the boiler at all times?

 

[rancher2]

I needed more storage for the Garn as it would take three full burns of locust or hedge in a 24 hour period in the cold months. During the winter my in town job would be 16 hours a day seven days a week. My wife doesn't like firing the Garn. I was looking for another 1000 gallons and found this 3000 gallon tank cheap. I had room in my pole building were the Garn sets so it was no problem to install it. My Garn is 10 years old so it still has just a timer to control the blower that controls the burn time. Garn now makes a stack temp set up that shuts the blower off when the stack temp goes down meaning the load of wood is burned. It is a learning curve to know how much time to set the blower for to burn a load of wood but not have the blower running when the wood is gone. I have enough storage that I don't have to worry about a full load of wood over firing the boiler and boiling it over. Before the extra storage I wood have to watch that. I should add a stack shut down system it probably would save some heat from going up the stack.

 

[Guswhit]

Do you have any idea how many pounds of wood you burn in a full load? How many degrees does a full load bring up your 5000 gallons of water?

 

[rancher2]

Guswhit
I am not running a heat exchanger between my storage tanks. I haven't weigh a full load of wood in the Garn. I just measured the firebox for the first time and its 40"L 25"W 27" H. Know the fire box is rounded so that's a quick measure before I fired it up. The Garn manual says with the model I have it will hold 155 pounds of Oak and that will give you 50 to 60 degree rise on the water temp. That is with the factory 2000 gallons. I usually see some were around 20 to 25 degree rise with a full load of hedge and three hours on the blower timer. We have a fairly large heat load with the house and my shop and I burn 10 to 15 full cords a year and that's good hard wood. I should keep track of how much I burn in the off season to heat the domestic water. We keep the old three story farm house pretty warm in the winter. It does have good insulation and newer windows. I haven't bought propane in 10 years.

 

[cumminstinkerer]

gonna and this and see where it goes havent had a chance to do anything yet was away for training last week