Swimming pool as a storage tank?

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Do you ever need to replace the water you have in the Non-Pressurized Storage tank with clean water? How do you prevent bad things developing there (E-coli etc)?
 
I think burying it makes sense with enough insulation.

A nonpressurized tank should be sealed, IMO. First, to keep it from becoming a huge humidifier, and second, to keep bad stuff out. They can go bad on you, and I'm told it smells pretty bad, but I don't think it's a major problem for most people.
 
Beno said:
Do you ever need to replace the water you have in the Non-Pressurized Storage tank with clean water? How do you prevent bad things developing there (E-coli etc)?

I have a non-pressurized tank. I used bromine-treated water to start with, and I have a layer of paraffin melted onto the surface to minimize evaporation. Probably acts as an antibacterial seal to some degree. I have an EPDM sheet caulked to the tank lip as well. I heat it to 160 degrees, which ought to discourage bacteria. I haven't looked at it since I put it in more than a year ago. Probably will open it this spring.
 
I've always wondered about your paraffin layer, nofossil. I assume it's liquid most of the time, no? It sounds like it would make a mess on an EDPM liner, but I'm thinking about doing it. Better yet, how about a couple cans of Udder Balm?
 
I guess you need some kind of drainage to be able to take the water out of the non-pressurized tank when you want to replace it, or service the tank. This is probably not good for the septic system.
Is there the same problem with the indirect? Is it easier there to replace the water?
 
Eric Johnson said:
Tarmsolo60 said:
Eric,
I saw the pics of your cistern and would be doing the same thing as you if that was in my basement. I was talking about someone who had to go out and buy a tank. It looks like you could build a duplicate of my tank cheaper than $2000 but as for using a different tank or swimming pool new and making it work I don't think you would be that far ahead of the game.

I totally agree. Other than saving money, one of my big motivators is (hopefully) the satisfaction of designing something and making it work. It's all part of the decision process, but it's nice to see people thinking creatively. Here's a pic of my homemade hx--half of it, anyway, sans fittings.

Thats a neat looking heat exchanger. what did you use a step drill? Phoscopper for solder? You will quickly get used to loading on your schedule not the boilers when you get that online. I made a fire Last night around 9:00 pm and its now after 4:00 pm and the top of my tank is still 140
 
Beno said:
I guess you need some kind of drainage to be able to take the water out of the non-pressurized tank when you want to replace it, or service the tank. This is probably not good for the septic system.
Is there the same problem with the indirect? Is it easier there to replace the water?

I emptied mine once and just used a little surface pump like you would for a hot tub.

Are you talking about an indirect water heater, that would just be domestic water in the tank. other than the Hx boiler water.
 
I used a step drill on a drill press and silver soft solder. The general consensus among the pros is that it won't hold up and I should have brazed it. But I'm a stubborn cuss and I'm going with what I've got. There are two identical units working as separate hxs--one for heat storage and one for recovery. Assuming that one is the storage hx, the recovery unit will nest down inside this one, but rising up to near the top of the tank. The piping on both will be reverse return to ensure equal distribution of the heat.

I'm really looking forward to getting it going. Running my boiler without it works fine, but the advantages to having that extra storage capacity are obvious, especially where summertime DHW is concerned.

You made the mistake of expressing interest. Here's a few more pics.
 

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Eric Johnson said:
I've always wondered about your paraffin layer, nofossil. I assume it's liquid most of the time, no? It sounds like it would make a mess on an EDPM liner, but I'm thinking about doing it. Better yet, how about a couple cans of Udder Balm?

Paraffin is barely solid at the coolest temps that my tank ever sees, and that's OK - think about old-style canning. If I ever need to drain it, the paraffin becomes easy-to-handle chunks, I hope. I also wanted something that didn't have any volatile components.

I guess you need some kind of drainage to be able to take the water out of the non-pressurized tank when you want to replace it, or service the tank. This is probably not good for the septic system.
Is there the same problem with the indirect? Is it easier there to replace the water?

Yeah, a drain would be good. I have one, but you could siphon it out as well. The bromine treatment is basically same as a hot tub, which is where the water came from. If I ever drained it, I'd just run it out on the ground. You wouldn't want to replace the water in a pressurized system because every time you do, you introduce more dissolved oxygen that eats away at your steel and iron components.
 
I decided not to put a drain in mine, because I didn't want to cut a hole in the liner. I'm thinking more along the lines of dropping a sump pump into the tank if I ever need to drain it. But a siphon would work, too.
 
I like the idea of using the cistern- I will be using three of my basement walls and building another to connect them to make a cistern of sorts when I go online with my boiler/hydronic/storage system.

One thing I am wondering about is if you used any rebar in the blocks and/or filled them with concrete. Mortar and surface bonding alone would keep me awake at night...


Chris
SW Wi
 
No, no rebar. The blocks are filled with vermiculite. I plan to rest the weight of the house on the wall with a jack and some framing. I can brace the whole works against the foundation, which is about 6 feet away, if I see cracks developing in the bonding cement surface. I do have a Plan B if this all fails.

Welcome to the Boiler Room, by the way, kuribo.

What kind of boiler do you have or plan to get?
 
I guess there is no advantage in buying an indirect 120 gal for $5000 if, for the same money, I can buy a 600 gal storage tank. If I'll manage to enter all these in my utility room on slab on grade, I guess I'll need an aditional post/footing under the slab, where the utility room will be.
 
I would think that adding rebar and filling the cores would be much easier, neater, and effective, but then what do I know....Simply placing weight on the wall may lead to other issues...Be careful!

I do not have a gasifier yet, but plan to cast some pieces to convert a used Royall boiler I picked up into a Seton style boiler. I also plan to have a masonry heater in the house with hydronic backup/augmentation.

Ultimately, I hope to have several heat sources (masonry heater, boiler, solar panels) all dumping into a 1000~2000 gal tank, which will then feed the hydronics, bathtub, domestic hot water.

This site is a great resource!

One question for nofossil (great site by the way!)...what is your btu/hr heat loss at your design point of your home?

Thanks all...

Chris
SW WI
 
I think the rebar in the blocks is an excellent idea. Wish I'd thought of that before filling them with vermiculite, but that stuff does flow, so it might come out with a few strategically placed holes at the base. I'll have to see if I have enough headroom to put the rebar in now.
 
Ideally, you would drill a few inches into the concrete floor every 12" or so, lay your first course, stick in the rebar with some epoxy, then fill the blocks with concrete. You can then lay the next course, repeat.

The problem you may face is that concrete block walls, while strong in compression (they support perpendicular loading well) are very very weak in tension, which is what you will get with the side loads. There is very little force required to move a block wall side ways.

You might consider forming up a 3-4 inch thick rebared poured wall inside your cinder block wall. If you tie the rebar at the ends into the existing concrete walls, you should be ok....

Chris
SW WI
 
Instead of pouring a wall, what do you think about building a 4-foot block wall filled with concrete right in front of the existing wall, using rebar like you suggest and tying a couple of horizontal pieces of rebar, sandwiched between the blocks, into the existing concrete walls?

BTW, which Royall model do you have? Are you using Seton's build-your-own kit, or something homemade?
 
Building a wall behind it as you mention, provided it is filled with concrete and rebar, should be fine. I would think though that removing the wall already in place would be a simple task if you choose to (re) do it....Be sure to drill into the floor and epoxy the rebar a few inches into the concrete...

The Royall is the mid-sized model, pressurized inside boiler. I will homebrew the refractory pieces to build a 2 chamber firebox which vents the combustion gas outside the firebox along the walls next to the water jacket, up, across the top, then down along the back like the Seton. Should work fine. Time will tell. I will not be able to get to this till next summer....

Take care-
 
Tarmsolo60 said:
I bought mine a couple years ago thats probably why it is $200 more now. So with the prices you just stated it seems like trying to save money on Hx would be a much bigger benefit than what you would save on the untested tank. I didn't buy my coils from them, they wanted $500/180' coil at the time. I figured I could make them cheaper, and I could have if I would have done them then. I waited and copper didn't get cheaper. I ended up buying soft L and making them.

So knowing you can buy a 957 STSS for $2000, how much cheaper can you construct a insulated tank around 1000 gallons?

My 1200 gal tank cost very little as it was made with materials that I scrounged at autions and yard sales.
Tank frame and insulation (old walk in freezer panels,4in foam)------$20
old carpet padding to protect epdm-----free
spray foam to fill cracks etc,---------free with rebates from menards
epdm-------$180
1-1/2 pipe and fittings for bottem hx.------$25
Stainless top hx 1/2in finned with fittings$40
steel reinforcing $20
6in temp guage----$1
6 blocks of parifin ( ideaThanks to nofossil)----$12
Water treatment----$100
LOTS of time and thought and redoes------FREE as I'm retired
leaddog
 
leaddog said:
My 1200 gal tank cost very little as it was made with materials that I scrounged at autions and yard sales.
Tank frame and insulation (old walk in freezer panels,4in foam)------$20
old carpet padding to protect epdm-----free
spray foam to fill cracks etc,---------free with rebates from menards
epdm-------$180
1-1/2 pipe and fittings for bottem hx.------$25
Stainless top hx 1/2in finned with fittings$40
steel reinforcing $20
6in temp guage----$1
6 blocks of parifin ( ideaThanks to nofossil)----$12
Water treatment----$100
LOTS of time and thought and redoes------FREE as I'm retired
leaddog

Could you post a picture of your tank?

Thanks,
Joe
 
Thanks for your help and advice, Chris. The cistern is actually 2,500 gallons. If I decide to tear the wall out, I'll probably just buy some more insulation and a bigger pond liner and turn the whole thing into storage. It's what I should have done in the first place. That's Plan B. Part of the cistern wall was torn out so that a previous owner could access it to dump trash and coal ashes, so I'll have to build another wall no matter what, but by doing it right this time, I'd get the benefit of a lot more storage which I've come to learn is a very, very good thing. So all things considered, it may be worth the effort and expense. Doesn't change my heat exchanger strategy at all.

The reason I asked about the Royall is that I ran a 6150 for 3 years and was impressed with everything about it except the inefficiency and smoke. I'll be interested in following your progress if you decide to document it here.
 
Yeah, it is always best to redo things if necessary to get them right- it is always more trouble and hassle to redo things down the road. I am in the middle of building a traditional Japanese timber frame home and I speak from experience here!

I will surely let folks know how the conversion works with the Royall. I bought it because it was built like a tank and looked simple and easy to modify...
 
I was just down there poking around again, and it's kind of exciting to think about the possibilities, but also kind of a bummer when I think about tearing down the wall. I'm not discounting anything, because I'd seriously like to expand the tank, but since it's so close to being done, I'd like to test out everything with the smaller tank for awhile.

So I'm thinking about quick & dirty ways to do that for the time being, that won't make expansion harder down the road.

If I filled the other side of that cistern up with plain water, say up to 4 feet on the existing wall (I think it's 5 feet tall), that would sufficiently support the wall, don't you think? I could actually use a cistern for our greenhouse (flat roof drained into this one at one time; now the flow is diverted into a leachfield with plastic drain pipe). But even if the water just sat there, it would be a pretty cheap, sure-fire way of making sure everything stays where it should.

Maybe bracing it against the foundation wall with planks and plywood makes more sense. If I wanted to brace that wall with, say, vertical 4x4s braced with 4x4s against the facing wall, what kind of spacing do you think would be best? It's about a 7 foot span.

Obviously just thinking out loud here, but any thoughts, observations or polite suggestions would be appreciated.
 
The time you spend trying to work around things will probably take as long as just redoing it. Adding water takes time, then you have to pump it out. With the humidity and other issues it will present, it really isn't an ideal solution. Bracing will take time too and end up being something you will redo, never mind the risks. As my German machinist Grandfather used to say, if it's worth doing, it's worth doing right.....

I would just bite the bullet and redo it the way it should be done....It doesn't take long at all to demo a cinder block wall....But I know it is hard to tear down something that took time and effort to do...just think about how much time and trouble you will have if that wall springs a leak!

Whatever you decide, good luck with it!
 
leaddog said:
Tarmsolo60 said:
So knowing you can buy a 957 STSS for $2000, how much cheaper can you construct a insulated tank around 1000 gallons?

My 1200 gal tank cost very little as it was made with materials that I scrounged at autions and yard sales.
Tank frame and insulation (old walk in freezer panels,4in foam)------$20
old carpet padding to protect epdm-----free
spray foam to fill cracks etc,---------free with rebates from menards
epdm-------$180
1-1/2 pipe and fittings for bottem hx.------$25
Stainless top hx 1/2in finned with fittings$40
steel reinforcing $20
6in temp guage----$1
6 blocks of parifin ( ideaThanks to nofossil)----$12
Water treatment----$100
LOTS of time and thought and redoes------FREE as I'm retired
leaddog


well that is much cheaper....the discussion earlier in the thread people were talking about purchasing different kinds of new tanks that ran about 1$ a gallon than making them insulated. I still think there is no new "factory" type tank you could buy, insulate, and make much cheaper than a STSS. I think you could duplicate the STSS tank and save some money, It doesn't look like the material for one would be outrageous, as for labor I usually take some of mine into account because I could be out working doing the same type of thing(plumbing/electrical contractor) and making money. I do admire the ingenuity of people that have the time and skill to build useful things and save money at the same time. I like you like making things work.
 
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