Indoor boiler advice needed

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They are 36" maybe 37". The weld on fittings I used were for a 36" diameter and they fit correctly. When I stacked them horizontally I spaced the support brackets to have ~12" from the top of the bottom tank to the bottom of the top tank to allow for connections between the two. Also the bottom tank is on 4" spacers to make connections on the bottom of that tank. So I agree that 85" would be too tight. Need about 90" unless you did those connections differently.View attachment 257037

Cross bracing was added to the steel supports and supports between tanks added since this picture was taken (before there are concerns voiced that they might fold over ;-)

Wow, slick setup. Is yours in a an outbuilding or a basement?
 
Cross bracing was added to the steel supports and supports between tanks added since this picture was taken (before there are concerns voiced that they might fold over ;-)
You stole my thunder with this comment the first time you posted this pic... ;lol
 
Wow, slick setup. Is yours in a an outbuilding or a basement?

Outbuilding - one I can drive my skid loader into. Makes things less challenging ;-)
 
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All I know is if I had to get dressed for a trip to an outbuilding I wouldn't have installed the boiler.
In my case every time i go to load the boiler i think of all the money i save by having it in a separate building. Plus i get to enjoy my favorite legal refreashment in a warm workshop.You noticed the warm workshop part...I have a warm place to go work on anything i like 24/7.It can be stinky, dirty and it doesn't matter,nobody gets their nose out of joint.
 
In my case every time i go to load the boiler i think of all the money i save by having it in a separate building. Plus i get to enjoy my favorite legal refreashment in a warm workshop.You noticed the warm workshop part...I have a warm place to go work on anything i like 24/7.It can be stinky, dirty and it doesn't matter,nobody gets their nose out of joint.
Yeah, I plan on building a large shop, large enough to fit my 38' class A RV for maintenance. A wood boiler in a dedicated room seems like the way to go. Long term the plan is to heat a greenhouse and grow food year round.
 
They are 36" maybe 37". The weld on fittings I used were for a 36" diameter and they fit correctly. When I stacked them horizontally I spaced the support brackets to have ~12" from the top of the bottom tank to the bottom of the top tank to allow for connections between the two. Also the bottom tank is on 4" spacers to make connections on the bottom of that tank. So I agree that 85" would be too tight. Need about 90" unless you did those connections differently.View attachment 257037

Cross bracing was added to the steel supports and supports between tanks added since this picture was taken (before there are concerns voiced that they might fold over ;-)
I was told 37 inches for a 500g. I was not doing my math right...85 inches would only allow approx 11 inches to connect and insulate. Could be done but Im leaning in favor of the 30x114 tanks. Slightly smaller footprint, but still would give 650 gallons.

How big of expansion tank is required for 650 gallons?

3fordasho....how did you make the plumbing connection between tanks?

Is it best to foam the tanks or box them in with Styrofoam? What kind of R value should I aim for in a compact boiler room set?
 
If I was stacking 500's, I would just rest one right on top of the other & weld lots of braces. Or maybe add a couple inches of channel in between to get a little space. I would have my fittings come out horizontal vs. out vertical out the bottom. Kind of like this:

p_00337.jpg


If I was stuck for headroom, that is.
 
I was told 37 inches for a 500g. I was not doing my math right...85 inches would only allow approx 11 inches to connect and insulate. Could be done but Im leaning in favor of the 30x114 tanks. Slightly smaller footprint, but still would give 650 gallons.

How big of expansion tank is required for 650 gallons?

3fordasho....how did you make the plumbing connection between tanks?

Is it best to foam the tanks or box them in with Styrofoam? What kind of R value should I aim for in a compact boiler room set?

I have this for 1000 gallons : https://www.menards.com/main/plumbing/pumps-tanks/well-pumps-well-tanks/water-worker-reg-119-gallon-vertical-pressurized-well-tank/ht119/p-1533623339182-c-1489153238829.htm
It's rated a bit lower temp than a more expensive expansion tank (Like 200f vs 230F) but in my install only the bottom 8" of the tank gets just warm to the touch even with the system at full pressure and temperature. I caught it on sale + 11% Menards rebate. My base system pressure at 50C storage temps is about .6 bar. With storage fully charged at ~82-85C it might hit 1.1 bar max pressure so plenty of head room yet. Relief valve set to 2 bar.
For 650 gallon storage system and following the same ratio you would need 77 gallon tank.
On the well tanks you lower the factory pre-charge from 39 psi - I think I went to 8 psi. Just like changing tire pressure.

tank connections between tanks : https://www.mcmaster.com/1698t12
To get the ports where I wanted I used a carbide tipped 1.75" hole saw to cut hole, then welded in the McMaster fitting. Then it's just 1.25" sweat copper between the two tanks.

I spray foamed the tanks individually, put into place, made connections, built 2x4 frame around and then sprayed a bit more foam.
1.5" foil faced foam on back wall and underneath bottom tank. R-13 fiberglass in 2x4 framing, 6" sheet foam over the top. Wrapped entire thing in sheet plastic and taped seams. Pretty good but could use more on the top and better sealing for the top.

20200111T135328.JPG


Here is the front of my storage tank enclosure - need to seal up the temperature readout panel.
 
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I was thinking 500's were 36" in diameter. I could be wrong, it has been a while.

But BadLP's comment could have been talking about setting them side by side.
Yes. A single 500 or pair of 325’s.
Of course a tight spacing of notched and welded pipes between the tanks keeps the overall height down too.
 
If I was stacking 500's, I would just rest one right on top of the other & weld lots of braces. Or maybe add a couple inches of channel in between to get a little space. I would have my fittings come out horizontal vs. out vertical out the bottom. Kind of like this:

View attachment 257051

If I was stuck for headroom, that is.
Very cool. I would have to stack them after hauling them down. I think it could be done tho.

I see a drain for each tank. The two bigger pipes are the lines going to the boiler?

Entering and leaving the tanks should be done horizontally anyway from what I've read.

I'm assuming you always want 2 pipes connecting the tanks?


Thanks for andll the info guys.
 
3fordasho: the mcmaster adapter looks great. I jotted that down. Would there be anything wrong with just welding in a section of pipe?

To anyone: what kind of thermometers should be used on the tanks?
Does the boiler need to read the temperature at the tank? or does this take place elsewhere? Or does this all depend on the type of boiler controller that is used?
 
I’m 92” total including a crap ton of top insulation. Both tanks have drains at the bottom for sediment purging. For temp and pressure I just used a standard off the shelf boiler gauge and I installed some access doors. 3015B7BB-461E-4896-9FDA-F55095E7B812.jpeg
 

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Very cool. I would have to stack them after hauling them down. I think it could be done tho.

I see a drain for each tank. The two bigger pipes are the lines going to the boiler?

Entering and leaving the tanks should be done horizontally anyway from what I've read.

I'm assuming you always want 2 pipes connecting the tanks?


Thanks for andll the info guys.

The two big ones in the middle just connect the two tanks. After I got them in place and finished the piping.
 
So you just have one pipe connecting the two tanks?

Yes. Can't see any reason to have more.

The other end has the boiler tappings. One very top & one very bottom. Also horizontal, like the other ones.
 
I travel around more in ohio than michigan. Where are you located?

My house wil be heated with the central furnace. I have the option of installing some radiant on the main level, but that's definitely going to wait.

I live about 35 miles SW of Cleveland.