New to Hearth - Questions (EKO 40, solar, open storage, oil backup)

[bonfire]

Hello Folks,

I have recently joined Hearth. Have been reading posts for some time now and decided to join.
I appreciate the wealth of information here.

This is my first post.

I have installed an EKO 40 and am in the process of adding open storage to the system and a controller, {still needed}.
We had an old 2000gal. oil tank which was underground and has been removed from service.
I Cut the tank, sand blasted it, welded all the bullet holes, painted it with 2 part epoxy paint.
Welded 6 tank taps along the top for connects.
I made up two heat exchangers, one for space heat/solar and the second for DHW. Its going to hold about 1150 gals.
Still have to finish the final connections and insulate the tank. See picts below.

The EKO 40 is located in the attached garage and the Oil boiler is in the basement of the house with all the zone circulators and
a radiant manifold for heated floors in specific areas.

I modeled the storage design from information I found from http://www.stsscoinc.com.

But first I was wondering if someone with more experience than myself could review my diagram and tell me if the following
makes sense:

Four way piping

Wood & Solar to House
Wood & Solar to Tank
Storage to House/DHW
Wood & Solar to DHW


WHAT HAPPENS WHEN YOU FIRE THE WOOD BOILER
Refer to Plumbing Diagram.

If the wood boiler is operating when the house is calling for heat, both the C-1 and C-3 circulators move heat
directly to the zone(s) in the house calling for heat. When both C-1 and C-3 circulators are pumping, heated
water by-passes the heat exchangers in the tank.

If the wood boiler is not fired, C-1 circulator and the Zv-l valve begin moving heated water from the top of the
tank heat exchanger to the house. Water travels bottom to top of the tank heat exchanger coils when removing
heat from the tank. Water travels top to bottom of the tank heat exchanger when the wood boiler is heating the
tank.

When circulator C-3 is operating by itself, heat is transferred to the tank. When C-1 is operating by itself, heat
is transferred from the tank to the house.

Two flow check valves placed in the same pipe, but in opposite directions (refer to the piping diagram
for this layout ), maintain a perfect balance between the flow of water from the boiler to the house regardless
of how many zones are calling at the time. Without these flow check valves there would be a constant
bleed-off of heat to the tank, even when all zones are calling at the same time.


Please note the following diagram

Below are addition picts of the project:

Thanks for any help,

Regards

 

[Nofossil]

Welcome to the forum. This diagram looks familiar ;-)

I'll post suggestions for sensors on the 'other' forum. I do have some questions about flow balancing. Still working on wrapping my head around this, and still on my first cup of coffee:

1) I think C1 got stolen during the night.

2) Seems to me that if several of the zone circs are running, there's nothing to prevent flow through the oil boiler.

3) By the same token, if only one zone circ is running, there's nothing to prevent backwards flow through the oil boiler (that's assuming that C1 and the wood boiler circ flows more than a single zone circ).

4) If several of the zone circs are running, it looks like they could also push cold water backwards through storage.

5) It's possible that when drawing heat from storage, you'll get ghost flow through the wood boiler. The forward resistance of the built-in check valve in the wood circ may not provide a lot more flow resistance than the flow check on the storage loop.

6) Finally. I assume that there's a mixing valve (not shown) for the radiant?

Nice drawing, by the way. You'll want to frame the final version and put it on the wall.

 

[hayrack]

Nice job on the tank. I would recommend that you T into the supply manifold with oil and wood on one end. As you have it now you have flow through the manifold. I tried this with flowchecks and it does not work. My system was piped similar to nofossils simplest pressurized storage. He has zone valves which would work fine. I had constant ghost flow or thermo siphoning piped like you are proposing. Dead end your manifolds so you don't have constant flow and just T into your supply and return. I just repiped mine this weekend and it works great now.

 

[hayrack]

I found that Bioheat or Tarm has excellent piping diagrams on there website. John Siegenthaler has the best piping diagrams for wood boilers and storage. He writes for PM magazine and there are several of his articles about piping to storage if you do a google search.

 

[bonfire]

Welcome to the forum. This diagram looks familiar ;-)

I'll post suggestions for sensors on the 'other' forum. I do have some questions about flow balancing. Still working on wrapping my head around this, and still on my first cup of coffee:

1) I think C1 got stolen during the night.

oops, fixed that and uploaded new diagram, thnx

2) Seems to me that if several of the zone circs are running, there's nothing to prevent flow through the oil boiler.

Yes, the circs run through the oil burner, I need to eliminate this burner in the future. Currently it has a DHW tank in it. I will be updating this oil burner with something else and fixing the piping.

3) By the same token, if only one zone circ is running, there's nothing to prevent backwards flow through the oil boiler (that's assuming that C1 and the wood boiler circ flows more than a single zone circ).

4) If several of the zone circs are running, it looks like they could also push cold water backwards through storage.

Not sure if this is the case with the flow checks. If it does happen I may add some additional zone valves. Maybe with the radiant circ always running this may not happen?

5) It's possible that when drawing heat from storage, you'll get ghost flow through the wood boiler. The forward resistance of the built-in check valve in the wood circ may not provide a lot more flow resistance than the flow check on the storage loop.

Good point, I took a short cut and used an IFC instead of a weighted flow check. Will have to see what happens.

6) Finally. I assume that there's a mixing valve (not shown) for the radiant?

Yes, there is a mixing valve, got lazy with the diagram, it is in one of the picts.

Thanks, for reviewing this for me.

 

[bonfire]

Nice job on the tank. I would recommend that you T into the supply manifold with oil and wood on one end. As you have it now you have flow through the manifold. I tried this with flowchecks and it does not work. My system was piped similar to nofossils simplest pressurized storage. He has zone valves which would work fine. I had constant ghost flow or thermo siphoning piped like you are proposing. Dead end your manifolds so you don't have constant flow and just T into your supply and return. I just repiped mine this weekend and it works great now.

I'm not sure where the "T" would go?

 

[jebatty]

Be very sure that you properly treat the water in that steel tank and monitor the water chemistry, especially pH. I started with an old oil tank for hot water storage, did not do what I urge you to do, and the rust was fast and rampant.