Help with storage plumbing

[warno]

I received my used propane tanks yesterday and would like to get started on putting in my ports as soon as possible so I can get started on the install when spring hits. I have two 250 gallon tanks that are going in horizontal in my crawl space. I'm needing advice on plumbing the 2 tanks to work with my system. I'm using a HX in the current duct work of the natural gas furnace, and I'll be running a sidearm for DHW.

I have this drawing that I made hoping this would be a good starting point.



The supply manifold would go in the top of the tanks and the return in the bottom. I drew them on the boiler manifold, but I wasn't sure where to plumb the HX and sidearm. either the boiler manifolds or build their own manifolds? Could anyone help me out with this plumbing? If any other information is needed let me know.

 

[lotawood]

The drawing makes it look like the tanks are vertical. Is that what you wanted to say, instead of horizontal?

Might want to add a check valve on the output of the boiler, if there isn't check valves on the pumps.

You could run the lines for the plenum HX straight to the boiler lines and balance the flow

 

[warno]

I'm definitely no artist by any stretch but I did mean horizontal when I wrote that. I only have very limited head room in the crawl space so I have to have horizontal tanks. The pumps I'll be using will have check valves in them.

 

[leon]

I received my used propane tanks yesterday and would like to get started on putting in my ports as soon as possible so I can get started on the install when spring hits. I have two 250 gallon tanks that are going in horizontal in my crawl space. I'm needing advice on plumbing the 2 tanks to work with my system. I'm using a HX in the current duct work of the natural gas furnace, and I'll be running a sidearm for DHW.

I have this drawing that I made hoping this would be a good starting point.

View attachment 174886

The supply manifold would go in the top of the tanks and the return in the bottom. I drew them on the boiler manifold, but I wasn't sure where to plumb the HX and sidearm. either the boiler manifolds or build their own manifolds? Could anyone help me out with this plumbing? If any other information is needed let me know.

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Before you go any further:

Please order at least 2 of Dan Holohans books from Amazon.
The first one is "Pumping Away" and the second one is Classic Hydronics".
With these tow books your going to prevent the mistakes you now have on paper
long before you start hacking and whacking.

Trust me the books are worth every penny and they will save you thousands of
dollars in mistakes-they did for me when I installed my Keystoker Coal Stoker boiler.

Unless your crawl space is insulated I would seriously consider changing the location of the tanks.
The ground temperature is going to be 52 degrees or lower in the crawl space and your propane tanks are
going to shed heat to the ground.

you will lose more heat to the ground than the tanks will give off to the floor, yes you will.

You need to revise your plumbing as well- the tanks need to be plumbed in series not series parallel this is only going to make
a mess for your plumbing and you will have no point of pressure change in that mess and your water is simply going
to sit there and not move.

Where is your Pump?? I hope it is on top of the boiler because you are going to be pushing a lot of air through the system
unless you change the tank plumbing to series plumbing.

if you install a steel expansion tank you will have a much easier time in doing plumbing and not require an air scoop
and the steel expansion tank will not fail like a bladder expansion tank will- We just changed the one on my father
boilers that has been bad for 2 years as my brother did not know what he is doing-typical.


Please Order the two books I mentioned as Dan helps the layperson and the plumber both understand hydronic heating.

I am just trying to save you thousands of dollars and headaches.

 

[lotawood]

I am not a plumbing expert. It was suggested to me to study Nofossil simplest storage diagram when I did mine.

I copied that design. I have a whole lot less going on than he does.

I thought a key item was how the boiler loop is tee'd into the distribution loop. That is what I copied. Mine works fine with zone valves on the distribution loop. You don't look to have zone valves.

You could think about piping in series thru 2 250 gallon tanks.

 

[warno]

I will have a pump pushing water from the tanks to the boiler which with the boiler being the high point in the system i would think should draw the water back down to the tanks. I'm curious what makes plumbing the tanks in series versus parallel is better? If the tanks have manifolds on the inlets and outlets wouldn't that make them act as "one" tank. I wasn't going to use zone valves but instead run my HX pump with a call for heat from the furnace. My DHW pump would run constantly.

 

[leon]

Please order Dan Holohans books.

ALL the water used for heating will move from one tank to the other.

The way you have your drawing the waters not going to move unless you have two circulators at the base of each tank making them nurse tanks and pulling water from them and pushing it to the heating load.

Your "single circulator" is going to be pushing against the total head pressure of the entire volume of water in the two tanks and then back up into the heating load.

YOU have to understand water is lazy just like electricity and will do what ever it wants and go where ever it want to unless you control it, plumb it right the first time, and make it go where you want it to.

Think of a marble traveling down the piping and follow it from the beginning to the end-at every tee the marble is going downhill,

The "Circulator" has to be on top of the boiler to eliminate air bubbles and slugs of air and doing this prevents circulator cavitation.

Your water is not going to move very well period!! like I said and the temperatures will stratify and "all" the water in storage will not be heated because it cannot be moved to the boiler and back again and the tanks will shed heat in to the crawl space.

Every restriction you install creates more head pressure and more resistance. Flooded suction for a circulator is best to push the hot water to the heating load.

I do not want you to attempt herding cats when you do not need to.

Its better to have the tanks as return buffer tanks to the boiler sump with the circulator pulling the water from the top of the boiler pushing the water to the heating load as the boiler will fire less.

 

[warno]

I don't know of it matters but I planned to do batch burns with this storage where the boiler pump will only run while the boiler is burning it's fuel then after the tanks are charged it will shut down and the HX pump will kick on/off with heat load and the DHW will run all the time. I can put the charging pump at the boiler that's no problem.

But I'm still confused why series tanks are better then parallel? I have seen many systems on here using parallel tanks and those people have posted having great results.

And you mentioned that I'll be losing heat to the ground. If I'm insulating the tanks how will I be losing heat any more then if I put the tanks right in my living room? I understand if I left them bare I will be losing a ton heat but with the insulation doing it's job should combat this loss, right?

 

[leon]

I don't know of it matters but I planned to do batch burns with this storage where the boiler pump will only run while the boiler is burning it's fuel then after the tanks are charged it will shut down and the HX pump will kick on/off with heat load and the DHW will run all the time. I can put the charging pump at the boiler that's no problem.

But I'm still confused why series tanks are better then parallel? I have seen many systems on here using parallel tanks and those people have posted having great results.

And you mentioned that I'll be losing heat to the ground. If I'm insulating the tanks how will I be losing heat any more then if I put the tanks right in my living room? I understand if I left them bare I will be losing a ton heat but with the insulation doing it's job should combat this loss, right?

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You have no where in the home structure where you can install these
tanks by the boiler??

Insulating the tanks is fine but with the tanks below and the boiler above them its still
not going to work well or very well with your plumbing diagram.

Order the two books I told you about and you will not not be making costly mistakes.

 

[warno]

There is no room in the house for the tanks and my boiler is an outdoor unit about 80 feet away.

Basically I'm trying to do what the attached picture is. Boiler charging the tanks, in parallel, and loads pulling from the tanks. Only difference is my tanks are horizontal not vertical. I suppose this drawing might be what you meant but "series parallel"? But either way that's what I'm trying to do. 2 tanks, 2 loads, and 1 boiler.

 

[leon]

If you can pour a slab and put a small shed by your boiler you would be able
plumb this a lot easier as you could keep wood in it and the tanks keeping them vertical
making your plumbing much more easy to install.

Your water is still going to be difficult to move the way your drawing is currently illustrated


At least I would like you to buy the two books I mentioned only for your peace of mind
as your making more work for yourself.

Disclaimer: I have no financial interests with Mr. Holohan or his publisher in any way.

 

[warno]

My drawing was simply a starting point of what I thought might work. That's why I started this thread for advice on how to make it better.

My problem with putting my storage anywhere but in the crawl space is I don't have the room in my yard for more outbuildings. I know plumbing them will suck with the low head room, but once it's done it will be done. I know is possible to do this I'm just looking for advice on the best way.

I'm glad to read that you have no beneficial gains from those books because I'm not going to lie I was starting to think that. Lol

 

[Bob Rohr]

Maybe this journal will help with some of your decisions. Ideally a single, tall, vertical tank is best for storing energy. You do want to stratify the tank, and vertical tanks allow for the best "stacking" In these drawings the tanks, of course could be horizontal.

One key concept is two pipe configurations. This allows all or any portion of the boiler output to go directly to the load. There in no reason to interface the tank volume when a load calls and the boiler is firing.

As the load lessens and or eventually satisfies all the output recovers the tank. then on the next call, energy comes from the tank if the boiler is off line.

Pay attention to the explanation of Extergy on page 6, this holds the key to stratification benefits.

http://www.caleffi.com/sites/default/files/coll_attach_file/idronics_17_na.pdf

 

[velvetfoot]

An excellent read. Though not a cord wood burner, I'm liking Fig 5-12, for simplicity.

Isn't it normal to have a pump or loading group to pump to boiler return? Most diagrams seem to have it this way.

Why only 500 gallons? (Logisitcs, I'm sure.) I recall your homebuilt gasifier is a monster.

There in no reason to interface the tank volume when a load calls and the boiler is firing.

Although the cool tank bottom water, or portion of it, still goes back to the boiler.

 

[warno]

Yeah it will be my home built boiler that I'm using. It's not a gasser though. I wish I would have built one, that's my 3 year plan. I plan to get this storage up and running for next winter then with any luck for the following winter I'll build a new boiler.

I'm only running 500 gallons because that's what I have room for. The storage is only heating my home which is about 1100 square feet. I'll read through that link posted and report back.

 

[velvetfoot]

1100 square feet

Wow, I remembered your boiler being pretty big.

 

[lotawood]

The idronics PDF's were very helpful in understanding a lot that gets talked about in the boiler room for me.

The Tarm diagrams and the simplest storage sticky also helped in planning my system.

Warno if you build a new boiler will it be a closed system/pressurized? I think you have an open system now and some of the drawings above are for pressurized systems.

 

[warno]

My boiler used a 30" diameter X 45" long propane tank for a fire box with a 7 feet long 6" X 10" heat exchanger over top of it. Heating about 120 gallons in the water jacket. I'm reading 450 degree flue temps. I'm working on getting better combustion and lower flue temps at the moment.

I actually talked to our inspector at work about the cost of a U stamp for a pressurized boiler. After hearing the cost of the stamp I probably won't go with a certified pressurized system. But I might still build a well supported pressurized boiler with the proper stay rods and relief valves.

I have previously read through the PDF that was posted but I'm working through it again. I'm starting to consider making my storage pressurized with a plate heat exchanger to charge it. I'm still trying to figure out my piping I need though.

 

[maple1]

I'm thinking you will get better stratification if you plumb them parrallel. Then the flow will be roughly 2x slower through each. But when it comes right down to it, it might not make much noticeable difference - mine are stacked, but piped in series, and I see good stratification. 'Fine points' like getting your inlet & outlet tappings as close to pointing horizontal across the tank might play a bigger part (and as close to the top & bottom as possible) - more downward/upward flow there would lead to more mixing and less stratification.

 

[warno]

So I'm getting alot of series and parallel being better or worse. And I'm getting very confused from that.

So as far as just the inlet and outlet on the tanks. I was going to use a piece of 1.5" pipe to make my "manifold" pipes between the 2 tanks then tie my 1" supply and return from boiler lines into the center of those manifolds. The inlet and outlet in the tanks were going to be as high, inlet, and as low, outlet, as possible. I planned to use a diffuser that I'll build for the supply lines. I'll simply take a section of pipe and weld a block off plate in the end then drill many holes down the length of that pipe 180 degrees from each other. The line of holes was going to be layed "flat" in the tanks to direct incoming supply water outwards instead of jetting straight in.

So as far as my original drawing goes, on just tying the tanks together, would the parallel as drawn work for me?

 

[leon]

So I'm getting alot of series and parallel being better or worse. And I'm getting very confused from that.

So as far as just the inlet and outlet on the tanks. I was going to use a piece of 1.5" pipe to make my "manifold" pipes between the 2 tanks then tie my 1" supply and return from boiler lines into the center of those manifolds. The inlet and outlet in the tanks were going to be as high, inlet, and as low, outlet, as possible. I planned to use a diffuser that I'll build for the supply lines. I'll simply take a section of pipe and weld a block off plate in the end then drill many holes down the length of that pipe 180 degrees from each other. The line of holes was going to be layed "flat" in the tanks to direct incoming supply water outwards instead of jetting straight in.

So as far as my original drawing goes, on just tying the tanks together, would the parallel as drawn work for me?

=====================================================================================================

I have one question; if you have room for a OWB and firewood why is it you cannot add a small shed for wood
and the tanks you bought to plumb them properly?


Please order the books "Pumping Away" and "Classic Hydronics" from Amazon before you make your problems worse. your going to spend a lot of money that you do not need to spend.

At least consult a licensed plumber and pay for an hour of his time.

 

[maple1]

So I'm getting alot of series and parallel being better or worse. And I'm getting very confused from that.

That might just mean, 6 of one half dozen of the other - there might not be one 'right' answer and it might not make much difference.

 

[warno]

=====================================================================================================

I have one question; if you have room for a OWB and firewood why is it you cannot add a small shed for wood
and the tanks you bought to plumb them properly?


Please order the books "Pumping Away" and "Classic Hydronics" from Amazon before you make your problems worse. your going to spend a lot of money that you do not need to spend.

At least consult a licensed plumber and pay for an hour of his time.

Since I'm in town, After adding my current boiler shed I have now it has taken up enough space on my lot that the city wouldn't give me my building permit for another outbuilding. So I'm stuck with putting them in the crawl space.

I understand that vertical tanks are best but why is it that one cannot plumb horizontal tanks correctly?

 

[Bob Rohr]

Since I'm in town, After adding my current boiler shed I have now it has taken up enough space on my lot that the city wouldn't give me my building permit for another outbuilding. So I'm stuck with putting them in the crawl space.

I understand that vertical tanks are best but why is it that one cannot plumb horizontal tanks correctly?

Sure you can pipe tanks in a horizontal orientation. The fluid circulating thru the tank really doesn't know or care how the tanks are placed. There are plenty of tank, especially the re-pourposed LP thanks that are still "on their feet"
>

 

[lotawood]

I think two horizontal tanks plumbed in parallel should be just fine.

I have one tank plumbed horizontal that works well. I just wish I had more than 500 gallons. I think vertical is optimal. Horizontal works OK for the stratification.

Two horizontal in parallel, plumbed with the supply and returns not pointing down/up: I think there is plenty of people here with that.