Expansion Tank - 125 Gallon Propane tank

[jwad]

I finished the underground lines for a new gasser and poured the floor in the new boiler room. Time to move on to the plumbing stage and get the ports done on the used propane tanks I received. I plan on using a 125 gallon propane tank as an expansion tank. There is 2 existing port about 12 inches from the bottom and 3 ports on the top dome. How high should the inlet pipe be? I will have a 1000 gallon propane tank for my water storage (need to work on the plumbing for that also). Any suggestings on how to plumb the tank?

 

[woodsmaster]

you need the inlet close to the bottom or on the bottom. Then all you need on the top is a shrader valve. I assume you are using the float gauge.

 

[91LMS]

let's wake this thread up. i need some help with this. doing the same to hope and save some money on a expansion tank. peeps having good luck and have a tested and proven design and parts list?

 

[altmartion]

can you not use a bladder style tank?

 

[91LMS]

sure could if the budget allowed it....

 

[altmartion]

sure could if the budget allowed it....

I understand. being that big it can be expensive, even at my cost.

 

[WoodWacker]

Is there any issue with using another smaller sized propane tank for expansion? Schrader valve for vac pump and nitrogen admission??? I'd like to think I could use stacked 1000 gallon tanks for storage but it would cost me 2 grand in bladder style expansion tanks. Using a 250 upright propane tank, with a water/nitrogen interface would give me enough expansion and keep my back pocket useful.

 

[maple1]

Yes - see my install thread in my Sig.

No input on nitrogen though...

 

[NE WOOD BURNER]

https://www.hearth.com/talk/threads/expansion-tank-volume.51241/#post-642119

Here is some interesting reading.

 

[WoodWacker]

Yes - see my install thread in my Sig.

Good deal. Love this stuff. I'm really leaning towards doing my own expansion tank, 250g propane with at least 1000 gallon storage. I love the setup you have maple. I'm most concerned with codes, I'll be taking out a loan to build a house, I doubt they'll like the looks of pressurized propane tanks filled with water in my basement.

 

[NE WOOD BURNER]

Since you are in process of building and worry about code. Why not take a look at the Garn jr. gives you storage and it is not a pressure boiler.

 

[91LMS]

wacker i built one as well with 1000 gallons of storage. been online for about a month. works like a charm.... well the expansion tank anyways, lol.

 

[maple1]

Good deal. Love this stuff. I'm really leaning towards doing my own expansion tank, 250g propane with at least 1000 gallon storage. I love the setup you have maple. I'm most concerned with codes, I'll be taking out a loan to build a house, I doubt they'll like the looks of pressurized propane tanks filled with water in my basement.

IMO that's a lot less worrying than 200 gallons of fuel oil in a tank - or even higher water pressures in a DHW system. I'm not a code guy though - so better check those things out if it's a concern, I guess. If you can find propane tanks (or air compressor) tanks with a pressure tag on them, that might help.

EDIT: BTW, if I was doing mine again I wouldn't do it quite like that. I would try to get the expansion tank up high, preferably higher than your highest system point. Otherwise everything the same. My jury is still out on whether I'm getting air in my system from this setup or not. I guess if I was to any extent I'd have noticed it after 1.5 years. I do get the odd air bubble working it's way thru the pipes, and the odd little gurgle at the top of my boiler when it's hot (say 190) - but haven't really had to add air or water into the system. I did this fall on startup, but that was a mistake - the low pressures I saw were from the syetem being stone cold, not from a pressure loss from something else. When I got it up to temp, I drained some back out. And my boiler manual shows an expansion tank setup like this for a closed system - it doesn't specify a bladder tank in that, which puts my mind at ease a little bit. All that said, I'm still thinking about how I can easliy change mine to get the tank higher - I could do it pretty easy if I put expansion in the master bedroom, but no way that one will fly...