storage connections

[Grapenut]

I'm planning on stacking 2) 500g ex-propane tanks horizontally on top of each other for storage. I want to run a line on opposite ends of each tank, from the top of the bottom tank to the bottom of the top tank. (I will weld in tank spuds). I'm planning on at least 3" lines. The easiest and cheapest way would be to use black iron nipples and a union, but I don't think I'll be able to get them to line up when I go to connect them. How have others done this? Hose with fittings? I've priced some out and the numbers I got seem pretty high. If there is an existing thread on this can someone direct me there? Thanks!

 

[in hot water]

Wow! 3" connections? If you could get by with 1-1/2 or 2" You could use those corrugated radiator hoses. Find them in all sorts of sizes and shapes. They can handle the temperature, with a barbed fitting maybe 30 psi max?

It's nice to have a little flex in connections that see wide temperature swings and expansion potential. On large boiler piping we do it with swing ells to allow some "give"

hr

 

[rkusek]

I'm not sure what a swing ells is but it sounds like something I did on my close boiler piping. Grapenut you are correct about it is tough to line everything up. I used extra 90's and a union to make it easier to "swing" together and match up the two lines. Instead of just a short straight connector, you would have something like a large U. The large radiator hoses mentioned above would give you more flex than iron. What about O2 penetration on these Hot Rod?

 

[woodsmaster]

I also used a couple of extra 90's to make things work. I didn't get my fittings perfectly square when I welded them.

 

[stee6043]

I think you might save yourself some headaches by not trying to make everything line up exactly. If I were you I would have the connections offeset by a foot or so and give myself enough room to come out, make a 90 and make antother 90 back into the upper tank. Below is how I connected and stacked my tanks but my connections are all on the tops of the tanks. I installed dip tubes from the top for my "bottom connections".

You can see one tank line coming off the top of my upper tank and going towards the wall before I come down and go back to the bottom tank. The other line (boiler supply) is hidden by the small expansion tank.

Simple stacking with racking. No welding.

Boxed in and insulated.

You do plan to have a connection for boiler return at the bottom of your lower tank as well, correct?

 

[RobC]

Many threads on welding tanks. I'm a decent welder. Getting watertight, pressure welds on a propane tank was humbling.

 

[Hunderliggur]

I brought all of my piping out to the end of the tank so when it is walled in I can access the balancing/shutoff valves from simple access panels. The 4" ports are for in tank heat exchangers. I now have one in the upper tank. There is another 4' fitting on the opposite end of the lower tank for a future solar input.

 

[henfruit]

Hey stee, Your pump motors look vertical ? I thought they needed to be mounted horizontal.

 

[stee6043]

Hey stee, Your pump motors look vertical ? I thought they needed to be mounted horizontal.

Indeed. It was part of my mythbusters episode on "do pumps really fail when mounted incorrectly". It turns out they do. Those Taco pumps were replaced long ago with some nice 3 speed Grundfos units mounted in the proper orientation. I'm glad I mounted them wrong because I really needed the 3 speed pumps to be happy with my system...and the failing pump on the boiler primary forced me to buy them!

 

[henfruit]

I am using 3 speed oor taco, What speed are you using on your grunfos?

 

[Grapenut]

I'm not sure what a swing ells is but it sounds like something I did on my close boiler piping. Grapenut you are correct about it is tough to line everything up. I used extra 90's and a union to make it easier to "swing" together and match up the two lines. Instead of just a short straight connector, you would have something like a large U. The large radiator hoses mentioned above would give you more flex than iron. What about O2 penetration on these Hot Rod?

D'oh! That's exactly what I'll do. I'll probably use 45's and a union. Thanks!

 

[toothy]

Hello All

I am getting ready to build the same kind of contraption. I built a 1000 gal unpressurized tank, but with the price of copper I'm going to go pressurized and avoid the copper, except for the domestic coil.

Is there an advantage from a thermal efficiency standpoint to orienting the tanks vertically or horizontally? My basement may not take them vertically, it's at just under 10 ft so they might need to be canted slightly for clearance. Some 500 gal tanks are just under 10' some right at 10.

Hunderliggur
What did you use for your 4" holes in the ends?

I'm using a tarm 2000 as a heat source.



Thanks
Wade

 

[woodsmaster]

I cant speak for the guys with horizontal tanks but my verticle ones stratify awsome. the top will get hot and the heat slowly works its way down when charging. The reverse when drawing off heat. Coldn't be happier with that part of my install. I wouldn't think it would make much difference in effency but may let you go a little longer between fires since you have more usable temp water on the top.

 

[henfruit]

250 gallons hot the tall way or the long way? is still 250 gallons i hope.

 

[RobC]

During the winter I need to recharge once a day regardless. I don't think you'd get that much more usable heat if they were on end. Some exceptions would be many tanks (like 4) so you had a large water volume at multiple tops or with a DHW coil you may be able to get some extra time.

 

[Hunderliggur]

I am still amazed out how evenly my horizontal tanks stratify. I don't think it makes much difference if your flow rates are reasonable. My piping is 1 1/4" at up to 10GPM with the input ftting on the top center of the horizontal tank.

I bought the tanks modified by AHONA with the boiler (I don't weld). They used 4" black iron (I believe) welded into the tank after cutting the hole. To get 4" plugs around here I had to go to an industrial plumbing supply house. None of the residental oriented suppliers had anything that big but the industrial house had bins and bins of the big stuff. I bought the in tank HX from AHONA and it slides right into the hole. It is finned copper tube (3/4") in a U shape about 36" long. I do get some left to right stratification when using the HX because of its placement but it does not really matter. I am currently pulling 60,000 BTUH out at peak, to be 90,000 BTUH when I upgrade one circulator.