Hot water storage tank ideas? Plans? Descriptions? Need input.

[welderboyjk]

I plan on putting in a wood boiler and also have access(maybe) a couple of older solar water collectors. I would prefer to bury a tank near the boiler/panels anyone have ideas on a decent way to put in a storage tank? I would prefer somethin LARGE. I have thought of digging a hole like a basement and laying a block wall with a poured floor(all insulated of course) with a rubber liner for the bottom and sides with just a lid on the top. Anyone heve any better ideas?

 

[semipro]

I've considered this for a solar installation also. I wondered if you could install a fiberglass septic tank underground and then somehow backfill with some sort of thermal insulator like broken up Styrofoam which you can get free from SIP and window/door manufacturers in some areas. You'd need to keep water out of the insulated zone to prevent losses that way. You could use foam board too but it wouldn't wrap around a round septic tank very well. I'm glad you started this thread and am interested to see what folks come up with.

 

[Eric Johnson]

Plenty of threads devoted to that topic in the Boiler Room.

 

[welderboyjk]

If you had a round tank you would not have to "wrap" it tightly. You could "square" off the hole and put in foam board with sand between your tank and the earthen sides. Care would have to be taken to backfill slowly and evenly, the sand inside the insulation would also add to the mass.

 

[bshatto]

I bet you could build a cistern out of ICF (insulating concrete form) then line with rubber.
Kind of what you already said.

 

[cguida]

A tank in/under ground might be awefully hard to work on in the event something goes wrong, like maybe a mole wonders into it or something...

Here's how I built my tank (above ground). Seems to work.

https://www.hearth.com/talk/threads/30706/

 

[ericjeeper]

Here is how we did mine. basically 600 gallons of storage.
http://www.pbase.com/ericjeeper/solar