Storage with Primary Secondary loop, layout?

[easternbob]

I've looked at Fossil's simple storage layout but not sure it's going to work with my system, which is set up as prinary secondary loops.

When I get home I draw it out (which I'm guessing will everyone's first question) and post it here. But I looked around and couldn't find any plans/layouts.

I'm trying to figure how to plumb the storage tanks into the system with the least about of fuss and $$.

Thanks!

 

[easternbob]

here's a sketch of the piping layout for my system.
Any comments on how I can plumb in a storage system would be appreciated.
Bob

 

[Bob Rohr]

here's a sketch of the piping layout for my system.
Any comments on how I can plumb in a storage system would be appreciated.
Bob

A few thoughts... Will both boilers ever run at the same time? How will you generate DHW? There are a number of ways to pipe P?s all with pros and cons, knowing what you total wants and needs are will help you pick the best option.

Is some of the system piped already?

 

[easternbob]

The drawing is of my existing system, so good or bad that's what I have to work with.

• No both boilers will never be running at the same time. In fact I shut off the elec. boiler and only turn it on when I go away for vacation.
• I have a simple side arm on my hot water tank to help supply DHW (didn't show it on the diagram to keep it simple). I have a hard water problem so it doesn't work that well. So if it has to go no big issue.

My goal is the is to install the storage in a simple easy way. If I have to opperate a valve or two say to by-pass the storage if house needs heat (say coming back from vacation) that is fine. Most of the time I should be able to keep the house and tank both warm. The house is smallish and very tight so my heat load is easy to meet.

 

[easternbob]

Just trying to refresh this topic (get it to the top of the board). It's summer and I'm guessing not as many people are reading right now....
Anxious to get rolling on this project.
thanks.

 

[Chris Hoskin]

the simplest thing would be just to put the tank or tanks in-line between the wood boiler and the closely spaced tees on your primary loop. This has the downside of creating a lag in getting heat from the wood boiler to the zones, but if you don't let the tank temps get too low, this should work fine with your low temp heating system (a bigger deal with high temp systems). For example, if you let your tank come down to 120F before you re-fire the boiler, and you are heating the floors with 110F, you would never notice any lag. What will you be using for tank(s)?

 

[maple1]

I was thinking what Chris said.

All you would really be doing is making your wood boiler a LOT bigger.

I don't think there would be a whole lot of lag - if the boiler-out goes in one side of the tanks at the top, and the tank-out goes out the other side of your tank at the top to the closely spaced T, the hot water from the boiler should go right across the top of the tank to your T without much delay. Aside from boiler warmup delay that is - it takes me about 20 minutes to get hot water to my system, from lighting the fire, on a cold start.

 

[easternbob]

Chris, So lets see if I understand what you are describing... see the attached image.
Does it matter if I choose option #1 or #2? They would both accomplish the same thing correct? Would option #2 be a little better as there would be less lag if the house was calling for heat at the same time the tank was heating? But will option #2 cause an issue if just the tank is calling for heat what will limit the flow towards the house? Is the pump in-line enough to limit flow and encourage it thru the tank instead.
I have a 320 gallon tank that I'm using in the horz. position. Hope to get away with the fittings that are already in the tank.
Thanks for the help/opinions!

 

[easternbob]

Maple,
So were you thinking option #1 of the diagram above? What do you think of #2?
Bob

 

[maple1]

Option 2 is more what I've got. But I've got zone valves in my zones, so nothing can flow there if there's no call for heat. Not sure if you have zone valves?

If not, Option 1 should be OK - but I would switch around the bottom pipes so you get cross flow as the hot water comes in the top - it will head for the opposite end. Otherwise you might get short circuiting on the boiler side of things & the other end of the tank won't get as hot as it should. If I said that right. Hopefully you'll get more feedback.

 

[Chris Hoskin]

Either option will work, but, option 2 will reduce/eliminate the lag getting heat out to the system. As maple 1 says, have your return ports at the opposite end of the tank from your supply ports. If there is any chance to get that tank vertical, I would recommend that too.

 

[easternbob]

I wish I could stand the tank vert. but don't have the ceiling height. I realize I won't get as good of stratification but work with what you got huh.
Does it matter if the second pump it need to install is on the hot side or cold?

 

[Chris Hoskin]

Probably doesn't matter too much, but we put pumps on the supply side - "pumping away" and all of that. Great boiler room, by the way, I hope you post pictures after the tank is in!