Freeze proofing my water tank

[Qweaver]

I have 1500 gal of underground water storage and 2300 gal above ground.  I've built a shelter to enclose my 1200 gal tank but I would like to use a wood fired heater in the shelter to help keep the tank above freezing.  Maybe even circulate hot water thru the tank as needed.  We never lost access to our above ground tank last year but there was about 6" ice on the sides and top in the tank.   Anyone have an idea of what kind of heater I could buy to do this?  I was thinking of putting my box stove in the shelter but i have no idea of how effective that would be.  I think that circulating hot water in the tank would be more effective...but how to do it?  I will always have access to my in-ground tanks if the above ground freeze up but I'd like to avoid that.

Thanks for your input, Quinton

[Ljohnsaw]

Well, first, do you have 2 tanks or 3 ???

How cold does it get there?  For how long? 

My first inclination would be to build a super insulated shelter (think rigid foam with minimal penetrations, like studs and rafters).  At least 6".  There should be no insulation on the floor - it should be bare earth, or perhaps concrete.  You want to make the most of the ground heat.  Ground temp (after you get to a certain depth) is a constant 54°F - well above freezing.  As long as you keep the outside air out, you should do quite well if your cold is not that cold (above 0°F?)

Heating water is an expensive proposition - takes a lot of energy, that's why you want free ground-source heat if possible.  If you have a super insulated enclosure, I think a 1,500w heater (on low = 750w) would probably keep it above freezing quite easily.  An oil-filled unit is nice.  Could even be a 100w light bulb.  Might want 2, so when one burns out, you still have heat.  Check out the thread on maple syrup - forget who it is in Maine.  They use a light bulb to keep an area above freezing.

[LittleJohn]

I would say wrap the tanks in PEX pipe, insulated and add another loop to the OWB  ;)
And use a switch to turn on the loop when tank temp reachs maybe 35F, and off at 40F.  BTW - use a mixing valve between tank and OWB, or your firebox might rain.


...but then again, I also hoard wood scraps, to feed the BEAST

[chevytaHOE5674]

What about some sort of a bubbler/circulator like people use to keep ponds open all winter long?

[Gearbox]

Why not circulate the water out of the underground tank to the above ground one . that underground tank has to be above 45 degrees . WV isn't north mn for temps .

[r.man]

I was actually thinking you could put a pipe loop in ground to circulate the tank water through but it would probably be easier to put a loop in the underground tank and then pump above ground water through and back to the above ground tank. I would use a small boiler circulation pump, at about 600 watts they are cheap to run 24/7 when needed. The better the insulation, the less you will need to run the pump.

[Gary_C]

They do sell all sorts of stock tank heaters with a thermostat that will keep the water just above freezing.

[Qweaver]

I have a 2100 gal above ground plastic and a 750 gal in-ground concrete tank that are plumbed into my inside water pump.  My 1400 above ground and other 750 gal are plumbed to gravity feed into my lower tanks as needed. Not ideal but it works OK. I just have to turn valves as needed.  There has never been a problem until we had 2 weeks of sub-zero temps last winter.  We never lost water pressure but there was 6" of ice on the sides of the above ground tanks.  I should probably install a 2100 gal underground plastic tank to replace the 1400 gal above ground.  I'm built on the side of a hill so gravity feed works well to refill my lower tanks that are feeding my pump.  We have a lot of metal roofs feeding our tanks so running out of water has not been an issue.  I can always refill my tanks from my cousins city water next door if we do run low.  He pays $15 per 1000 once he exceeds his max and my rain water is free so I would like to avoid that.  I currently only have about 3000 gal on hand so we may have to be frugal.

[47sawdust]

I don't believe I would do anything.As long as you are not in danger of loosing your water the ice will act as an insulator of sorts.If your tank is accessible you might consider hiring a spray foam contractor to foam it next spring or summer.You might have to coat the foam to prevent UV degradation or build an enclosure.Running hot water intermittently presents it's own problems and running a glycol loop runs a risk of contaminating your potable water.

[r.man]

I like Gearboxes idea about swapping underground tank water with above ground to utilize the ground heat for both tanks. If you had a sawdust toilet 3000 gallons would go a lot farther.

[Qweaver]

The enclosed shed that I built over the large tank is working well.  By the time I get it fully sealed and insulated I'll be in good shape.  The temp got below -5 and I had about 20 in the shed and an inch of ice and that melted quickly when temps got above 32.  Problem solved I think. 

[red]

I am told it is 71 in Texas  ?

[Kbeitz]

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