# anyone stacked 1000 gal propane tanks?



## cjdave (Nov 27, 2011)

Has anyone stacked 1000 gal propane tanks? I am kinda worried about the weight of the second tank on top of the first tank. I was planning on welding saddles to the tanks and welding them to each other. I have just enough room to do this where the tanks go and have about 4-6" above the top tank. I was thinking at least 4 saddles and making them out of 1/4" plate and bending the ends. Thinking I will need the same 4 saddles for the bottom tank to make legs for more support than the factory feet. Figure on tank weight is around 1900 and 1000 gal water 8300 means that top tank is 10,000 lb or so. Thoughts?


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## Frozen Canuck (Nov 27, 2011)

Assuming this is going on a concrete floor you will have no issues. Ahona.com (one of the site sponsors) sells a product just like this.


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## nrford (Nov 27, 2011)

No Problem!


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## goosegunner (Nov 27, 2011)

I thought if I ever add another tank I would make saddles for in between but I would connect them by welding in short pieces of well casing.

What do you think? Weld in 4 or so pieces of 6" well casing.

gg


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## maple1 (Nov 28, 2011)

That's a lot of weight - wish my basement had room for that much storage.

So far, it looks like I'm going to be using 330 gallon tanks (that's what they called them - 9' long by 30in diameter). I don't have a whole lot of extra room to work with. I was thinking of using two & stacking, but building a 4x4 wood frame between tanks - which would also be part of the framework for insulating & boxing them in. Not sure whether I should rest one right on top of the other, or have the top one sitting independant on its own framework - just in case something happens to one of them and I have to replace it or pull out to fix (my luck). Good thing I have all winter to try to plan this stuff...


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## infinitymike (Nov 28, 2011)

I might be concerned with the saddles on the concrete. You might want to consider putting wide steel plates under each saddle to help spread the load.


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## cjdave (Nov 28, 2011)

Yes I was planing on putting plates on the lower saddles to spread the load on the concrete. Ok, sounds like I should be fine.


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## cjdave (Nov 28, 2011)

goosegunner said:
			
		

> I thought if I ever add another tank I would make saddles for in between but I would connect them by welding in short pieces of well casing.
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> What do you think? Weld in 4 or so pieces of 6" well casing.
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> gg



That's not a bad idea, any worries about expansion/ contraction with heat cycles? I might look into this I have the capability to do it. Would make the whole thing stronger for sure and add the connections at the same time.


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## goosegunner (Nov 28, 2011)

cjdave said:
			
		

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Not sure about expansion or contraction, you could seek out the thickest wall pipe.

The advantage would be nice big connections between the tanks with stability.

Disadvantage would be moving it around!  Even my single 1000 was tuff to move. If you weld two together make sure that you elevate the bottom one in nice big saddles and give yourself big base plates to distribute the weight. It might be kind of top heavy until you get it stabilized.

gg


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## Garth B (Nov 28, 2011)

I welded 2 800gal tanks together. The factory legs on the upper tanks stradeled the lower tank nicely so i just welded them in place like that.  I didnt provide any extra support under the lower tank and the factory legs are holding up fine, as they should... I think they were formed 1/4" pl. So in the end it required no extra fabrication other than a couple pieces of pipe from the top tank to the bottom tank and the half couplings for my other various connections. I did put metal plates under the legs on the concrete floor, probably didnt need to as the floor is 12" thick under my tanks.


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## cjdave (Nov 28, 2011)

goosegunner said:
			
		

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Yea weight is a problem, but I worked for structural steel company for a while and we moved heavy stuff all the time, sometimes it's about having the right plan and knowledge (a bunch of friends that are professional equipment riggers don't hurt either!) . Plan right now is  to weld them together on there sides, move into place and stand them up. It's a plan in progress, but needs to happen this week or weekend...


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## goosegunner (Nov 28, 2011)

Make sure you have someone take plenty of pictures!

gg


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## cjdave (Nov 29, 2011)

Ok, so here is what I am thinking: 
But would it be better to put both the 6" pipes on 1 end and put my feed and return on the top and bottom tank at the same end?


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## maple1 (Nov 29, 2011)

My thought is if you put the return & feed on both tanks at the same end, you'd want to put the 6 inch at the opposite end, for better run around flow (so to speak) & hopefully better stratification. I'm thinking about doing that, except using a short run of external pipe at the opposite end to go out of the bottom of the top tank & immediately in to the top of the bottom tank.

That's a nice pic - and a lot of weight to tip upright. Might make decent Youtube footage.

Good luck!


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## Jersey Bill (Nov 30, 2011)

I dont think the lower tank is designed for that kind of load. It is designed for large pressure from within.


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## Chris Hoskin (Nov 30, 2011)

why so much storage?


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## DaveBP (Nov 30, 2011)

It might get a bit tricky welding the 6" dia. couplings down in between those tanks if the tanks are close together. Those have to be not only strong structurally but need to be absolutely watertight.


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## cjdave (Nov 30, 2011)

Tarm Sales Guy said:
			
		

> why so much storage?



Heating 3 buildings and DHW. with a 80kw boiler summer/winter. I just don't want to wish I had done more.


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## cjdave (Nov 30, 2011)

DaveBP said:
			
		

> It might get a bit tricky welding the 6" dia. couplings down in between those tanks if the tanks are close together. Those have to be not only strong structurally but need to be absolutely watertight.


Yea that is one of the problems I am working on, I might go on the end instead of in the middle It's tight, but I am pretty sure I could get in there with the stick welder ( I have a welding cert for Structural stick welding). I would hate to have a leak after there in place and full....


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## Garth B (Nov 30, 2011)

I used 1.25" pipe to connect the two tanks (as well as welding legs to top of lower tank) If you are only sending cool water back to the bottom of the tanks, what is the advantage of such a large pipe joining them? My upper tank probably wieghs around 8000lbs, sounds like alot but split it up over 6 points of contact with the lower tank and its only 1300 pounds per contact.

The 1.25" pipe I used to join them was pluged at both ends and sloted on the sides so it wouldnt shoot water straight up or down in the tanks.  IMO cutting such a large hole and getting a tight fit would be more hassle than it was worth.  If your just after extra support, I would keep the welds and extra material on the extrerior of the tank.

For moving mine I lag bolted (2) 2x6 on the bottom and used them as skids, then pushed it across my driveway and into the woodshed with a tractor.  Tipping them upright was the harder part as my tractor does not have a loader, I had to jack them up to a 45 degree angle then pull them upright with the tractor.


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## cjdave (Jan 16, 2012)

Just a update:
Here is a rendering of the final design. I am putting fittings in the tanks this week and hopefully stacking the end of the week. I will post some pics as the progress goes. All the saddles are made just need to get everything welded together.


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## Singed Eyebrows (Jan 16, 2012)

Garth B said:
			
		

> I used 1.25" pipe to connect the two tanks (as well as welding legs to top of lower tank) If you are only sending cool water back to the bottom of the tanks, what is the advantage of such a large pipe joining them? My upper tank probably wieghs around 8000lbs, sounds like alot but split it up over 6 points of contact with the lower tank and its only 1300 pounds per contact.
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> The 1.25" pipe I used to join them was pluged at both ends and sloted on the sides so it wouldnt shoot water straight up or down in the tanks.  IMO cutting such a large hole and getting a tight fit would be more hassle than it was worth.  If your just after extra support, I would keep the welds and extra material on the extrerior of the tank.
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> For moving mine I lag bolted (2) 2x6 on the bottom and used them as skids, then pushed it across my driveway and into the woodshed with a tractor.  Tipping them upright was the harder part as my tractor does not have a loader, I had to jack them up to a 45 degree angle then pull them upright with the tractor.


Garth, 8000 lbs or 800 lbs? That top tank can't weigh that unless its made from 1/2" plate, Randy


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## maple1 (Jan 16, 2012)

Singed Eyebrows said:
			
		

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I suspect he meant filled weight?


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## cjdave (Jan 16, 2012)

Has to be full weight, 1000gal x 8lb/gal. 
 My 2 1000 gal tanks full of water the whole thing should weigh in just under 20,000lb.


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## Garth B (Jan 16, 2012)

I did mean filled weight but that number was a bit high, a more accurate number is 5125lbs for each of my tanks (full) assuming I have 500gal tanks which I think I do.

On a side note, getting -13deg F nights now, and I am really enjoying the extra storage! (first winter with storage)


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## Singed Eyebrows (Jan 16, 2012)

Garth B said:
			
		

> I did mean filled weight but that number was a bit high, a more accurate number is 5125lbs for each of my tanks (full) assuming I have 500gal tanks which I think I do.
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> On a side note, getting -13deg F nights now, and I am really enjoying the extra storage! (first winter with storage)


I wish I had that storage Garth. I'm going to need to find another tank over summer, Randy


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## cjdave (Jan 17, 2012)

made some progress on the lower tank...


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## cjdave (Jan 18, 2012)

Test fitting the upper tank. Still need to weld fittings to the upper and leak test both tanks, then weld them together.


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## maple1 (Jan 18, 2012)

What material did you use for the cradle brackets? I'm anticipating doing this but with smaller tanks (330gal) - haven't had a chance to talk to my welder guy about it yet. I was thinking it would be easier just to let the tanks sit right on top of one another & weld some straight bracing in, not using a cradle setup. Input on that? Are you connecting (flow-wise) both tanks by welding too, or doing that with pipe & fittings?

Looking good BTW.


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## huffdawg (Jan 18, 2012)

cjdave said:
			
		

> Test fitting the upper tank. Still need to weld fittings to the upper and leak test both tanks, then weld them together.



Wow looks great!  what are you lifting with chain hoists.   Thats lots of storage.


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## cjdave (Jan 18, 2012)

maple1 said:
			
		

> What material did you use for the cradle brackets? I'm anticipating doing this but with smaller tanks (330gal) - haven't had a chance to talk to my welder guy about it yet. I was thinking it would be easier just to let the tanks sit right on top of one another & weld some straight bracing in, not using a cradle setup. Input on that? Are you connecting (flow-wise) both tanks by welding too, or doing that with pipe & fittings?
> 
> Looking good BTW.


Brackets are 1/4" steel plate, I cut them out on my cnc plasma table. the good thing about using cradles is it spreads the load out on the tanks, I feel in my setup atleast where I am putting close to 10,000 lbs of tank and water on top of the lower tank I wanted to spread that load as much as I could. The tanks will be connected by 3 2" manifolds and those 3 manifolds will be connected to my boiler supply, return and load returns.


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## cjdave (Jan 18, 2012)

huffdawg said:
			
		

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4000 lb forklift, its hiding on the other side of the tanks. I figure with the new Vigas 80 LC hiding in the corner I should be able to run that much storage pretty good. I will be starting a new thread on the full install once I get to that point. It's been like Christmas every couple days with UPS bringing more supply's...


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## wolfcreek (Jan 18, 2012)

Great thread. Overall I'd certainly agree with anyone that a better fit and weight distribution mounting system is worth the effort as is maximizing space utiization.

I've been pondering this step in my install also. I plan on two 500 gallon tanks and have entertained thoughts of a cast concrete bed and center support. I'need to get some information on how much the tanks expand, anti-abrasive lining, type of concrete to use, where I need access, etc. but it would seem I'd be increasing the storage mass, reducing the surface-to-air exchange and be giving the tanks and floor an ideally distributed support system.

Another thought would be mounting the tanks conventionally but fabricating glycol tanks (open) within the support framework to act as thermal mass.


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## cjdave (Jan 18, 2012)

wolfcreek said:
			
		

> Great thread. Overall I'd certainly agree with anyone that a better fit and weight distribution mounting system is worth the effort as is maximizing space utiization.
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> I've been pondering this step in my install also. I plan on two 500 gallon tanks and have entertained thoughts of a cast concrete bed and center support. I'need to get some information on how much the tanks expand, anti-abrasive lining, type of concrete to use, where I need access, etc. but it would seem I'd be increasing the storage mass, reducing the surface-to-air exchange and be giving the tanks and floor an ideally distributed support system.
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> Another thought would be mounting the tanks conventionally but fabricating glycol tanks (open) within the support framework to act as thermal mass.


How would you insulate to stop heat transfer into the slab?


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## maple1 (Jan 18, 2012)

wolfcreek said:
			
		

> Great thread. Overall I'd certainly agree with anyone that a better fit and weight distribution mounting system is worth the effort as is maximizing space utiization.
> 
> I've been pondering this step in my install also. I plan on two 500 gallon tanks and have entertained thoughts of a cast concrete bed and center support. I'need to get some information on how much the tanks expand, anti-abrasive lining, type of concrete to use, where I need access, etc. but it would seem I'd be increasing the storage mass, reducing the surface-to-air exchange and be giving the tanks and floor an ideally distributed support system.
> 
> Another thought would be mounting the tanks conventionally but fabricating glycol tanks (open) within the support framework to act as thermal mass.



Concrete. Huh. Now there's an idea. Aside from a chop saw and bubble gumming with an old Lincoln welder we have here, I don't have much skills or tools for metal fabbing - but I can make plywood things to hold concrete until it dries and even mix my own if it wouldn't take a whole lot.

I think that is worth more serious thought.


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## wolfcreek (Jan 18, 2012)

There are mixes of concrete that have different coefficients of heat, some mixes being touted as effective insulation, others great thermal mass material. It seems to me that a cleverly cut set of forms could cast a mounting system that could also support an insulating shell and component mounting points.

I guess the real question is the benefit to the effort of adding thermal mass as opposed to increasing the thermal store that can be transferred via circulation? With all that space between the circles and the squares that round tanks offer, and as efficient as I'm trying to get, I don't want to cover up an opportunity.

I'm still in the predesign stage so I'm thinking as far out of the box as I can.


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## DaveBP (Jan 19, 2012)

This is about as close together as you can get a couple 500 gallon propane tanks. Doesn't look like it but the tanks are up against each other inside the belly band around the middle. Overall height is 78" off the floor when resting on its legs.


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## goosegunner (Jan 19, 2012)

DaveBP said:
			
		

> This is about as close together as you can get a couple 500 gallon propane tanks. Doesn't look like it but the tanks are up against each other inside the belly band around the middle. Overall height is 78" off the floor when resting on its legs.



Is that a saddle or is it actually open flow between the tanks?

gg


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## DaveBP (Jan 20, 2012)

> Is that a saddle or is it actually open flow between the tanks?



The tanks are hydraulically connected to each other through 3 flame-cut holes (each end and the middle) about 4" X 4" but otherwise are intact under the skirt piece connecting them.


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## cjdave (Feb 9, 2012)

Stacked and in...


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## goosegunner (Feb 9, 2012)

cjdave said:
			
		

> Stacked and in...



Nice, Very Nice!

What did you end up with for height?

gg


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## cjdave (Feb 10, 2012)

floor to top of tanks is 87.5" 
Worked out really well. Carpenter is here today to frame walls all around so I can insulate. Hoping to start plumbing next week!


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## goosegunner (Feb 10, 2012)

How did you end up connecting the two tanks?

I have considered adding more storage but it would be a chore now that mine is closed in.  With 2000 gallons I could go every day with out my wife having to mess with it. Oh well hindsight, would change several things.

gg


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## woodsmaster (Feb 10, 2012)

cjdave said:
			
		

> floor to top of tanks is 87.5"
> Worked out really well. Carpenter is here today to frame walls all around so I can insulate. Hoping to start plumbing next week!



 You blowing cellulose ? That's what I used for mine and I'm happy with the results. It was a lot cheaper than foam or I probably 
would have used that.


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## cjdave (Feb 10, 2012)

woodsmaster said:
			
		

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Actually that was my next dilemma. I was wondering if anyone had done cellulose, as it would be the easiest way to do it for me.. 
kinda leaning that way.


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## cjdave (Feb 10, 2012)

goosegunner said:
			
		

> How did you end up connecting the two tanks?
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> I have considered adding more storage but it would be a chore now that mine is closed in.  With 2000 gallons I could go every day with out my wife having to mess with it. Oh well hindsight, would change several things.
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> gg



going with a 2" manifold on both ends and in the middle, the connecting via a welded pipe coupler ended up being more work than i thought neccacary. I will get some pics once i start plumbing.


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## woodsmaster (Feb 10, 2012)

cjdave said:
			
		

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It works good. I would get everything operating for a couple of days and make sure there are no leaks. Then when you blow it
dense pack the insulation. Actually push it down with a stick or somthing. It will increase the r- value and wont settle.


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## Der Fuirmeister (Feb 11, 2012)

You blowing cellulose ? That's what I used for mine and I'm happy with the results. It was a lot cheaper than foam or I probably 
would have used that.[/quote]
Actually that was my next dilemma. I was wondering if anyone had done cellulose, as it would be the easiest way to do it for me.. 
kinda leaning that way.[/quote]

I used loose fill fiberglass (hand placed, not blown) around my Garn.  Roughly R40 in the narrowest spaces, otherwise up to 2 feet thick.  Worked great.  Was readily available, easy to place and cheap.


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## goosegunner (Feb 11, 2012)

What the heck you have a Garn and a woodgun, what are they used for?

gg


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## Der Fuirmeister (Feb 11, 2012)

goosegunner said:
			
		

> What the heck you have a Garn and a woodgun, what are they used for?
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> gg



The Garn heats the shop and the Wood Gun heats our house and DHW.


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## goosegunner (Feb 11, 2012)

Der Fiur Meister said:
			
		

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How would you compare them, either one stand above the other for efficiency or ease of use?

Do you have storage with the woodgun?

gg


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## cjdave (Feb 11, 2012)

should I worry about the feet of the tank sitting right on the concrete, like should I try to isolate the steel feet from the concrete say with a plywood shim to stop some heat transfer or am I just getting crazy now?


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## Der Fuirmeister (Feb 11, 2012)

goosegunner said:
			
		

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Both are very good.  They operate differently, and have their own benefits.  The Garn really needs it's own outdoor housing.  We used a 20' long ISO shipping container.  The Wood Gun is installed in the lower level of my home.  Both have a vacuum induction fan vs. a fan that pressurizes the fire box.  If either unit leaks they simply suck in air.  I chose the Wood Gun for my home because I like the idea of making a fire in the morning without having to walk out in the snow and 4* temps (like it was here this am).  I've watched my neighbor filling up his outdoor "smoking hut" in the cold wind.  Doesn't look like fun.  His is a non-gasification type and he burns almost twice the wood I do with a smaller home.  

Efficiency is about the same.  There were variables in the tests, but I've read independent lab reports showing the Garn in the low to mid 90% range primarily depending on the water temperature in the tank.  The Garn flue temps range from 300* to 350* at the stack (up to 400* inside at the gauge).  The WG is almost too efficient.  I'm careful to keep the flue temps above 230* minimum with normal temps running in the 270* range.  I've never seen it go above 305*  

We use the Garn to burn scrap wood from shipping crates etc.  The Garn handles nails with no problem.  The WG does not handle nails.  Cleaning the ash from the Garn is easier, just using a square shovel.  The WG is a bit more tedious.  I use a wood ash vacuum cleaner which helps.  Being an open tank type testing the Garn is more critical.  Both light very easily and in a similar fashion.  Turn on the fan put the newspaper on top of the dry wood or kindling and light.  I can run them both with the door open.  I liked the manual timer Garn has on their controls so much that I installed one on the WG.  That way it doesn't keep running when the fire goes out (and suck the heat up the flue).  Burning the WG into storage greatly reduced the amount of creosote in the flue compared to the first year when it cycled on and off.

The WG really should have a seamless SS pipe or pipe with the joints sealed with high temp tape etc.  I have sectional black pipe now, but fabricated a flue pipe from Sch. 10 SS pipe.  It will be installed during the next warm spell.  The new flue pipe has flanged / gasketed doors on it at the bends to make inspection / cleaning a 10 minute job.  No more worries about leaking pipes.  We vent our Garn upwards (vs. down into a barrel as Garn recommends) with 15' of pipe just to reduce the smoke during lighting.  After the first 5 min. it's just steam for the most part, but with the unit only 10' from the shop I'd rather not have any smoke at all.  The shop roof and walls are steel so I'm not worried about sparks.  I intend to make a spark arrestor / heat recovery barrel that will sit under the exhaust elbow and then vent upwards.  The barrel will have an outer jacket for the intake air to run through and be preheated before entering the Garn.  Next year's project....

The Garn can be over fired, the WG just shuts down, but I try not to run the WG that hot.  Right now I have 100 gals. of temporary storage on the WG plus a 215 gal DHW preheat tank, but I'm in the process of welding up a 750 gal. tank from 12 gauge 201SS sheet and 304SS angle.  201SS sheet is much cheaper than 304.  I have a similar 215 gal. SS storage tank that I made for the DHW preheat tank.  A pex HX is used to transfer heat to the DHW preheat tank.  300' of 1" pex runs through it from my well before going into my LP hot water heater.  The preheat works so well that we no longer use LP.  

The Garn needs to have fire brick replaced every other year....cheap brick - $12, easy 10 min. job.  The WG needs to have the center brick replaced every 7-8 cord, for me roughly every other year.  Haven't done that yet, but it's due.  The brick run $140 from AHS plus freight which was estimated at $50.  So I decided to buy 50 lb of refractory cement and make my own.  I suspect replacing those will take a few hours.  

The Wood Gun has had wear on the door gaskets.  I'll be replacing those in a few weeks.  I added an "L" shaped piece of sheet metal to the rear door where the hot gases and ash sand blast the door gasket.  This seems to be working well.  When I replace the gaskets I intend to add the sheet in the high wear areas.  Hopefully this will extend the gasket life to 3-4 years.

It was difficult getting information directly from Garn, but the rep I bought from in MN was very helpful.  Wood Gun from AHS doesn't have reps in WI and information from them has been variable with the change of personnel they've had.

Both are excellent units.  Both made in the USA and I'd recommend either one, depending on your circumstances.....or if you're like me, both.


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## Der Fuirmeister (Feb 11, 2012)

cjdave said:
			
		

> should I worry about the feet of the tank sitting right on the concrete, like should I try to isolate the steel feet from the concrete say with a plywood shim to stop some heat transfer or am I just getting crazy now?



I can't imagine there's much heat transfer from the steel to concrete in that small surface area.....


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## cjdave (Feb 12, 2012)

Der Fiur Meister said:
			
		

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Well with the way I build my feet I have full saddle contact with the tank 30" long and the foot is 6" wide, so that gives me 5 square feet of surface contact with the floor. 5 Sq ft is quite a bit of contact and I know how good concrete is at sucking the heat out of anything warmer than it.


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## mikefrommaine (Feb 12, 2012)

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Don't know if you need it, but it seems like cheap insurance to put wood under the feet. I would consider using  pressure treated.


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## goosegunner (Feb 12, 2012)

I put 6 layers of pressure treated wood under my tank's feet. It was advised here that the loss would be very minimal through that much wood.

I then added 8" of polyiso foam board under the tank covering the concrete. It was a pain to cut the pieces but I got it for free.

gg


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## cjdave (Feb 12, 2012)

unfortunately I only have about 3.5" above my tanks to the ceiling, that means what ever i put under the tank feet needs to be 1/2" or at most 3/4". I guess there is a chart somewhere that gives r values for plywood?..... yep found it 1/2" plywood is R-.63 and the standard rating is plywood is R-1.25 per inch. so 3/4 ply would give me about R.9. dose not sound like much but i guess its better than nothing...


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## Der Fuirmeister (Feb 12, 2012)

mikefrommaine said:
			
		

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You could if you are concerned.  The Garn has a continuous foot running the length which is about 9 inches wide and welded the entire length.  Garn recommends setting the boiler on (2" R10 I believe) foam board, but with that much footing area (~14.25 sq. ft.) the foam can handle the weight (~15,000lb).  It ends up at 7.3 psi.  Standard Dow foam is rated at 15 psi and they usually have the stronger 25 psi foam available at lumber yards.  You can get up to 100 psi foam as well.....  http://building.dow.com/na/en/products/insulation/rigidfoam.htm

Do you know the weight of your tank?  If you have 5 sq ft. (720 sq. inches) and get the 25 psi foam it could handle up to 18,000 lb.  I would recommend looking into it if you're concerned.  Is the concrete in your basement with all the parasitic heat loss going into your house anyway?  My Wood Gun is in my basement and only has the 1" insulation which it came with.  The basement stays a comfortable 68 degrees all winter.


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## Der Fuirmeister (Feb 12, 2012)

cjdave said:
			
		

> unfortunately I only have about 3.5" above my tanks to the ceiling, that means what ever i put under the tank feet needs to be 1/2" or at most 3/4". I guess there is a chart somewhere that gives r values for plywood?..... yep found it 1/2" plywood is R-.63 and the standard rating is plywood is R-1.25 per inch. so 3/4 ply would give me about R.9. dose not sound like much but i guess its better than nothing...



I'd much rather have another inch above the whole tank than an inch below just 5 sq. ft. of it.  Do the heat loss calcs on the loss at highest tank temps at the top over the whole area vs. the lowest temps on the bottom and just 5 sq. ft.


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