What do you think of this as a tank for storage (unpressurized)

What do you think of this as a tank for storage (unpressurized)

It is stainless interior with insulation. Two foot man hole, drain. About 600 gallons -- seller will get actual dimensions for me soon

Seems like a LOT of space for only 600 gal. I know a guy that was using one with grease in it for biodiesel production. They have chiller coils in them if it's a milk tank like it looks.

It is a milk tank. Said it has an agitator that can be removed. Don't know about coils.

If it was a milk tank.. they USUALLY have coils that run thru the insulation area along the tank for cooling. Like I said.. Nice stainless tank. BIG scrap value. BUT.. bet it's almost double the size of a 500gal propane. Way heavier. If that's a consideration.

If the space is not a consideration..... If it does have the coils, I assume they are brazed to the tank for continuity, if they are sized correctly you could use it(them) for DHW. It would be very well insulated too.

I don't think it would be that much bigger then an LP tank when you take into the consideration the fact that's already insulated.

I thought of using one of these in my setup but never really went hunting for one after I looked into my tank. I really like the idea that it's SS, you can't get much better then that!

K

Seller is asking 1000 for the tank. What do you think is a good price?

I'd consider you could most likely get two 500 propanes for less than that.. and then about 800 or so for spray foam. So unless you only think you need 600 Gal.. I'd keep looking. If 600 is all you need.. It's not a bad solution. Are their high and low ports? If not.. now you're talking stainless welding. Not rocket science, but getting around and thru all that insulation and water jacket to the tank will be a PITA. I would think for unpressurized storage.. one of those rubber bladder tanks would be made to your specs and price would be similar. Never really got pricing unpressurized.

My apologies.. if you run unpressurized you would just access via the man ways with coils right? You'd do what.. a dip tube kind of arrangement to pull your cold from the bottom.. and boiler output dumped in the top?

I paid $1 per gallon for a 1000 gal. 10 years ago. That was the going rate for salvage milk tanks for a lot of years. Not sure what they go for now.

Hooking up your plumbing can be challenge. I had a 4 inch port added. Most milk tanks will have a 1 1/2 or 2 inch drain port in the bottom and an opening in the top. The ports are not NPT, you will need to find an adapter fitting. They also will have a man sized opening in the top with a lid. If you have an "open " boiler it can be a problem having and "open " storage tank. Of coarse some kind of heat exchanger would solve that problem.

The tanks are insulated very well and work for storage if you can work around the open tank problem

I haven't found prices anywhere near that for propane tanks, you have a source?

As far as the milk tank goes I would be using a copper coil as ahead exchanger.

U need just one? There's a lot on Washington Ave Auburn. It's webber. Not sure if they will sell em. I MAY have an extra one next week.

I keep hearing about cheap LP tanks but I never saw them. The cheapest thing I found was a 1000 gallon tank for a grand and it's wasn't all that great condition wise. Add in the cost to get it welded up the way I wanted and it wasn't by any means cheap. Most of the big dealers would rather their old tanks go to scrap then sell them these days....

If I was going to spend time converting something, I would use something like the tank we're taking about here. Throw a coil in it and you don't have to have all that water pressurized (no missile in your basement), setting up DHW or adding solar would also be pretty darn easy. Another plus would be there would be no temp limits, something I have with my setup.

I know you guys love your LP tanks but there are other options.

K

Id like to have two, but if you have one for sale I'd definitely be interested.

The biggest downfall I see to An unpressurized tank is the cost of the heat exchanger.

I go round and round on what would be best or setup. Between expansion tanks, insulation, heat exchangers and size never mind cost per gallon it gets confusing. My wife won't even talk to me when I mention pressurized vs unpressurized. Good thing I have you guys.

A dollar a gallon is still the going price for milk tanks. Not sure what the R-value is. Isn't much, can't be an inch thick. I think it's less than an inch. Still might need to insulate the outside? the freon lines inside the jacket are useless for anything. Chances are, they got a leak some wheres. especially if its a Surge brand.

Looks like an old Zero, I'd forget the cooling coils they are most likely junk 1/gallon is all milk tanks sell for at auctions, these tanks are designed to keep milk cold for about 12 hrs at 80 degrees if there is a failure .

Thanks for all the info. I knew nothing about milk tanks. It seems like it might not be the right tank for the price of me.

I have a couple of different leads on propane tanks thanks to this forum.

There are all kinds of them in Moncton, NB - if you don't mind a longish drive & trying a border crossing.

I guess I will be a contrarian and recommend the milk tank. Unless you buy a brand new propane tank with appropriate connections or have certified welder with an ASME code stamp do a code alteration to the propane tank, you now are potentially operating with a unlicensed pressure vessel. Even though many people do it and dont have an issue, if it does let loose and does damage, the insurance company does not have to pay a dime for repairs as its an illegal install. On the other hand an unpressurized stainless tank is going to last forever and its legal to install.

If you are near Searsport stop by and talk to Tom Goce at American Solartechniques about a coil and the installation. (He is Tom in Maine on this site). He has a real slick non pressurized boiler set up like Dick Hill's boiler that is set up for a non pressurized tank ((he cant sell it yet as its not EPA certified). I bought one of Toms tanks as I needed to get in through my bulkhead but if I had had a spot, I would have bought the milk tank.