One 500 gallon tank, 1 circ pump - Will it work ?

[Seyiwmz]

Guys, I finally found a propane tank. My current system consists of an EKO 40 and 1 circulating pump. I want to install the 500 gal. tank. I have 3 zones that are fed by the same pump. I'd like to enjoy the benefits of early and consistant 170-180 degree boiler temps. My pump pushes the intake water into the boiler. I'm trying to figure out the types of mixing valves I'd need. I'm trying to stay as simple as possible. I'm not as concerned about achieving stratification maximization. My first idea it to put a 3 way mixer on the backside of the pump. I was wondering if anybody else has a similar setup? I've seen other diagrams out there, but not with 1 pump. Any ideas appreciated. Thanks

 

[jebatty]

I stretched on this one, and every scenario I ran through ended up not working. Then, voila, why even bother with trying to get by on one pump when Taco 007 can be had on Ebay for $50 or so. What's an extra $150 after spending the dough for the boiler, storage, plumbing, etc.? Good luck.

 

[barnartist]

Sey,
Other guys can tell you on paper how to do it scientifically. With one pump you can go from the top of your eko, to your demand (house heat), in the bottom of your propane tank, out the top, then your pump and back into the eko's bottom. place the pump near the eko return. Of coarse you need at least a nice sized expansion tank in there, 500 gallons really changes more than what you had without it. If your going to mix any water, mix it so the the eko gets a warm mix right back into itself. If you plan to keep a burn going continuous, the mix is not as important as it would be if you plan to run your system down and restart from cold (cold tank-maybe 100-120). What you will find is you will have a more consistant water temp with your tank installed, it really acts as an absorbsion of the return water. I have a similar setup- I can by-pass my 500 gal prop. tank but rarely do because of how the eko bounces its temp without it.
This is only what I am doing, and only a suggestion. This works MUCH better than without a tank, but for me I still need at least 2 more 500's because I heat my house and the one tank too easily on one load of wood.

 

[barnartist]

Jim is right though, 2 pumps will ease the thouht of pump failure too.

 

[Nofossil]

I spent a lot of time trying to come up with the simplest scheme that would work. What I ended up with is a circulator pump for each heat source and a zone valve for each heat load. The storage tank can be either a source or a load, so it has both. Here's a plumbing diagram. I have more info on my site - link is in my signature below. This a pproach would work the same way for a pressurized tank - just eliminate the middle heat exchanger in the tank.

 

[Seyiwmz]

Thanks Guys, Got some ideas now. I was cleaning out the tank last night while it was still above freezing temps outside. It was pretty clean, but had that stink to it. I used some bleach and Tide detergent in there. Hopefully it's clean enough. Does anybody know the weight of one of these tanks. I ran over the scales at the scrap yard where I got it. They put it at 1200lbs. I thought that was high because I was rolling it around in the snow pretty easy. Thanks for the insights, Seyiwmz

 

[verne]

500 gal should weigh about 950 lbs .A 1000gal is about 1750-1800 lbs. Let us know how you make out getting it into place and hook up.
I am still debating between a 500 gal or 1000 gal.