Piping Redraw

[huffdawg]

I have redrawn my piping schematic I have put the alpha pumps on the bridges between the boilers and the primary loop. Should I put a zone valve in the return to the primary loop from the gas boiler so that it wont heat the wood boiler when it comes on.
I will also be adding more closely spaced tees for future use like storage ,overheat loop, shop heat and dhw.
Can you put your overheat loop on the primary loop or should it be on the wood boiler circ.

where should your storage closely spaced tee's be on the primary loop. before the house load or after?

Thanx Huff

 

[Donl]

Huff, I think you should review your concept of primary/secondary piping. What you are showing on the diagram simply won't work. The primary loop needs a circulator.

How long are the two bridge loops coming off the primary loop?

 

[in hot water]

You're getting warmer... Yes you do need a circ in that primary loop to "stir" things up. The other option is to buy, or build a tank with four large ports and build a separator, or primary loop in a tank. That eliminates one circ, gives you a tad more thermal storage, some air removal and a dirt settlement area.

I like the one Elliot built, you can buy a plain steel, pressure rated compression tank, aka expansion tank for around 150 bucks. Have a welder add the 1-1/4" ports where they work best for you.

You have all the right stuff, just get it all aligned for best performance.

Here are two simple piping options. The one with a separator could also be a buffer tank, a supersized separator do to speak.

The next shows one method of piping a primary loop where the heating, and DHW load could be controlled with two pumps or a pump and zone valves.

Not trying to confuse your plan, but it is best to work it out on paper first and find the piping that best serves your application.

Credit schematics: John Siegenthaler 2006

hr

 

[huffdawg]

ok will add a circ to the primary loop . I should of known that. been looking at a lot of drawings lately.
The bridge that supplies the gas boiler loop would be about 8' long and the bridge coming off the wood boiler circ. would only be about 4' long.
What circ pump would be best for the primary loop. 3 speed circ ,alpha , or just a simple low cost circ. like the 007. or comparable grunfos.

I like the separator idea but I dont think its right for my set up because of the run of 1-1/4 pex undergound to the house its 50' one way and I wanted to tie into this loop later on for a hot tub supply. Would it not be best to keep this whole 1-1/4 run as a primary loop also the Gas boiler is plumbed in 1" .

Sorry for all the different drawings ive posted . but I want to make sure its all going to work . I am investing a lot of money into this . As you all already know.
I will only be home till Sat. And I would like to get most of the near boiler plumbing and the primary loop close to it done.

Thanx Huff

 

[Donl]

The bridge that supplies the gas boiler loop would be about 8' long and the bridge coming off the wood boiler circ. would only be about 4' long.

Thanx Huff

If the bridges are only 4 feet and 8 feet long why not eliminate the bridges all together and closely tee the boiler loops directly onto the Primary Loop. This will save a couple of unnecessary pumps and added electricity to run them.

 

[huffdawg]

That sounds great to me as long as it will work. Wheres the best spot on the primary loop to install the circ . So its pushing the hot water to the load.

 

[Donl]

That sounds great to me as long as it will work. Wheres the best spot on the primary loop to install the circ . So its pushing the hot water to the load.

You can install the pump on the primary anywhere it is convenient, just not too close to any tees. How long is the primary loop?

 

[in hot water]

This is how I ran my system last year. Ignore the large tank, consider that your primary loop.

I repiped recently when that buffer/ separator tank came my way. The only issue with last years piping was the need to heat the 500 gallons before I could move energy to the radiant. Now the EKO heats that 50 gallon buffer in 15 minutes or so even from a cold 60F start up. On mild days i don't need to heat the 500 gallons, build a small fire and transfer directly to the load.

With this piping you have a few choices. The EKO has the ability to run the boiler pump. Mine would turn on at @ 155F and off @ 140F. At least that is how my 2005 version EKO 40 is setup.

That really does a adequate job of boiler return protection without needing that 3 way thermostatic valve. No need to balance and mess with a 3 way, and they do use a small amount of your pumping head. It does so by switching the pump on and off a bit until the boiler hits it's stride. that cycling is the only drawback to a bang/ bang control.

As a second level of protection I ran that circ on the cross over as a delta t with variable speed. So as the boiler hits say 155f that circ kicks on at 100% speed. After 20 seconds it drops to 30% (adjustable) speed. For every 10 degrees the boiler temperature rises (adjustable) the pump speeds up one step. So it moves the amount of energy the boiler is producing, exactly.

The pumps can be any size, (1 amp or less) off the shelf wet rotor. Taco, Grundfos, Wilo, B&G your choice. Size the pumps to the load they are moving. I suspect a Grundfos 15-58 on speed two will cover your application. The control will vary the speed as needed, a fixed speed Grundfos 15-42 might be even cheaper to purchase..

I'll bet you can find a dual output solar control online for about the same $$ as a large thermostatic, and now you have two functions covered with some energy monitoring functions also.

OR both the boiler pump, and the crossover pump could run off the dual output solar control. Both on a variable speed function. Set the boiler pump to fire on when the boiler reaches a min. temperature, 155F works for me. With both pumps working off a delta T AND variable speed you are always moving the energy around at the exact rate needed and with the least amount of electrical energy. No need to use an Alpha here, save it for the zone distribution circ where it can use it's intelligence wisely.

hr

 

[bigburner]

see a lot of confusing piping on this site. build a primary loop pull all your secondary loads & supply's off the primary by using the double T method. Start with both boilers either one first - then DHW - then base board - then in-floor loads all being down stream from supply.hottest to coldest. Looks like six pumps to me. the primary loop can run continuously & eko, the rest all cycle with load and you don't need any zone valves. I will put spring checks in but it really not necessary, some times you will get an induced flow in a low head circuit. Do it this way and it will work every time. addig later is a breeze also. I would make the loop so there is at least a couple ft between sets of tee's more if you got room.

 

[huffdawg]

see a lot of confusing piping on this site. build a primary loop pull all your secondary loads & supply's off the primary by using the double T method. Start with both boilers either one first - then DHW - then base board - then in-floor loads all being down stream from supply.hottest to coldest. Looks like six pumps to me. the primary loop can run continuously & eko, the rest all cycle with load and you don't need any zone valves. I will put spring checks in but it really not necessary, some times you will get an induced flow in a low head circuit. Do it this way and it will work every time. addig later is a breeze also. I would make the loop so there is at least a couple ft between sets of tee's more if you got room.

Big burner in the drawing at the top of the thread,the gas boiler and all the circs in it are allready existing . I dont want to replumb all that at this time . I would be tieing into it at those closely spaced tees just below the GB. even those are not plumbed in yet.

My Gas boiler is in an attached garage about 50' away from EKO. Basically the gas boiler will be at one end and the EKO at the other. It sucks but it is the way it is for now.

All the pumps on the Gas Boiler setup should pull through it and from the primary loop as suggested By Don L.

Thanx Huff

 

[huffdawg]

That sounds great to me as long as it will work. Wheres the best spot on the primary loop to install the circ . So its pushing the hot water to the load.

You can install the pump on the primary anywhere it is convenient, just not too close to any tees. How long is the primary loop?

Well in total its roughly 100' long round trip . There is about 40' that is buried and another 40' in my crawl space and whatever I add at each end to complete the loop. I have enough room in my EKO boiler room to space out the primary loop circ and any closely spaced tees.

Huff

 

[Donl]

That sounds great to me as long as it will work. Wheres the best spot on the primary loop to install the circ . So its pushing the hot water to the load.

You can install the pump on the primary anywhere it is convenient, just not too close to any tees. How long is the primary loop?

Well in total its roughly 100' long round trip . There is about 40' that is buried and another 40' in my crawl space and whatever I add at each end to complete the loop. I have enough room in my EKO boiler room to space out the primary loop circ and any closely spaced tees.

Huff

Next question. Where are all your loads? Are they all at the house end? Where will you locate storage eventually?

 

[huffdawg]

That sounds great to me as long as it will work. Wheres the best spot on the primary loop to install the circ . So its pushing the hot water to the load.

You can install the pump on the primary anywhere it is convenient, just not too close to any tees. How long is the primary loop?

Well in total its roughly 100' long round trip . There is about 40' that is buried and another 40' in my crawl space and whatever I add at each end to complete the loop. I have enough room in my EKO boiler room to space out the primary loop circ and any closely spaced tees.

Huff

Next question. Where are all your loads? Are they all at the house end? Where will you locate storage eventually?

At the moment all the loads are in the house which the GB is taking care of for the time being. My EKO boiler room is in an attached room on the back of my detached shop. I have enough room for 3 330 Gal. tanks in my Eko boiler room.

Eventually I will be supplying heat to my shop floor which has 4 200' loops of 1/2" pex and the upstairs in my shop I will install staple up. It has the same floor space as the slab.
And also DHW for the shop.
I will plumb all these onto the primary loop later . but I will plumb closed spaced tees for these loads now.

Huff

 

[huffdawg]

This is how I ran my system last year. Ignore the large tank, consider that your primary loop.

I repiped recently when that buffer/ separator tank came my way. The only issue with last years piping was the need to heat the 500 gallons before I could move energy to the radiant. Now the EKO heats that 50 gallon buffer in 15 minutes or so even from a cold 60F start up. On mild days i don't need to heat the 500 gallons, build a small fire and transfer directly to the load.

With this piping you have a few choices. The EKO has the ability to run the boiler pump. Mine would turn on at @ 155F and off @ 140F. At least that is how my 2005 version EKO 40 is setup.

That really does a adequate job of boiler return protection without needing that 3 way thermostatic valve. No need to balance and mess with a 3 way, and they do use a small amount of your pumping head. It does so by switching the pump on and off a bit until the boiler hits it's stride. that cycling is the only drawback to a bang/ bang control.

As a second level of protection I ran that circ on the cross over as a delta t with variable speed. So as the boiler hits say 155f that circ kicks on at 100% speed. After 20 seconds it drops to 30% (adjustable) speed. For every 10 degrees the boiler temperature rises (adjustable) the pump speeds up one step. So it moves the amount of energy the boiler is producing, exactly.

The pumps can be any size, (1 amp or less) off the shelf wet rotor. Taco, Grundfos, Wilo, B&G your choice. Size the pumps to the load they are moving. I suspect a Grundfos 15-58 on speed two will cover your application. The control will vary the speed as needed, a fixed speed Grundfos 15-42 might be even cheaper to purchase..

I'll bet you can find a dual output solar control online for about the same $$ as a large thermostatic, and now you have two functions covered with some energy monitoring functions also.

OR both the boiler pump, and the crossover pump could run off the dual output solar control. Both on a variable speed function. Set the boiler pump to fire on when the boiler reaches a min. temperature, 155F works for me. With both pumps working off a delta T AND variable speed you are always moving the energy around at the exact rate needed and with the least amount of electrical energy. No need to use an Alpha here, save it for the zone distribution circ where it can use it's intelligence wisely.

hr

IHW ,right now I have 2 alpha pumps and a taco 007 that came with the EKO . I just want to do the primay loop method right now. Although I realy like your idea of a buffer tank as a primary loop . It might be possible to add later . Don L has suggested going without a circ on the bridge to the Gas Boiler. Can I still omit the danfoss without the buffer tank primary loop

 

[bigburner]

if you called me I would not tie into this with out knowing what the sequence of operation was. that means a picture & schematic which I would produce on your dime. my suggestion is to draw it exactly the way it's piped now. don't skip any thing.and include controls, then show where you want future equipment. By the way does the gas boiler system work the way you want?? More pictures also,straight on and back a little & a couple shoots of the room/area

 

[huffdawg]

if you called me I would not tie into this with out knowing what the sequence of operation was. that means a picture & schematic which I would produce on your dime. my suggestion is to draw it exactly the way it's piped now. don't skip any thing.and include controls, then show where you want future equipment. By the way does the gas boiler system work the way you want?? More pictures also,straight on and back a little & a couple shoots of the room/area

Here is the actual buderus drawings.

I have had 3 different contractors here and none of them are interested and they have all seen the drawings and 1 claimed to have spent a couple months back east at Buderus installers course. After talking with him for 10 mins. I wouldnt let him touch it anyways. All three wanted to tie in ways that would not work.
I have sent emails with questions about sequence of operation to the guy that built it. but no reply's. Have also tried buderus they dont want to talk to an unqualified guy. Maybe someone on this site can get that info.

The Gas boiler works fine for the house but it will not heat the shop and living space above it as well.
Huff

 

[bigburner]

looks like the simplest way is to, make your primary loop just to the left of the expansion tank [on this drawing] but be fore the first mix valve, tie those two horizontal lines together and put every thing on the left [all three zones] tied in to that loop as one secondary loop, then tie in the wood boiler some where in the primary loop, with double tee's. This works from a hydraulic stand point, now the control. the issue is the GB boiler will try to cycle on when zones are calling. I think I would put a strap on aquasat on the supply line from the wood boiler and break the line voltage to the venter motor. It should work as normal, except the water will circulate threw the boiler. I can't be positive would need more information. I would post the drawing just don't know how.

 

[in hot water]

The Buderus drawing is close to what you need/ want. As Don mentioned I would take off the high temperature loads first. Tee the EKO into that loop with closely spaced tees. If you want the wood boiler to heat dHW, then tie it into that loop also, remove it as a parallel load on the Buderus as it is now.

Manufacturers will generally send "canned" conceptual drawings. it's really up to the installer to fill in the blanks or customize it to your exact spec.

They like to refer the work to someone trained in their product to avoid problems, potential warranties, etc.

That is one reason they have that pump package built. in my hometown by the way, to hang on the bottom of the Buderus. That assures the boiler is piped and pumped properly. The installer takes it from there.

All of the drawings attached to this thread will accomplish your goal. They all apply the same concept, just a different look.

It's always best to visit a jobsite to formulate the exact plan, sometimes it's hard to communicate all the finer piping details, or options, via a 'putrer screen.

Hydronics is fairly forgiving but some basic principles need to be followed, especially with todays high efficiency boilers.

 

[bigburner]

don't need to worry about high temp loads here - my way - puts all current loads in the secondary loop and the lower temp stuff is tempered any way. The control is going to be the issue, we always keep the existing system alive and will come on with low wood boiler water temp. It also keeps the factory built manifold in place, cut that out and the sky's the limit. Personalty I would cut it out replumb/rewire the whole thing and what ever I wanted, BUT kinda been doing this a while. Keep it simple.

 

[huffdawg]

don't need to worry about high temp loads here - my way - puts all current loads in the secondary loop and the lower temp stuff is tempered any way. The control is going to be the issue, we always keep the existing system alive and will come on with low wood boiler water temp. It also keeps the factory built manifold in place, cut that out and the sky's the limit. Personalty I would cut it out replumb/rewire the whole thing and what ever I wanted, BUT kinda been doing this a while. Keep it simple.

I apologize , that buderus drawing isnt the same as my system. Here is my own drawing of my system. If you have any questions as far as piping and components that you need to relate from the drawing to the pic. I'll try to answer them.

Huff

 

[huffdawg]

What I see as the easiest way to tie in is to cut the 1" copper pipe just above the DHW return (the horizontal pipe just above the black pump)
Then cut the pipe between the red and blue isolation valves .
Drop the black pump assembly down enough to fit in closely spaced tees above the DHW return pipe.

As far as controlling everything I was hoping to leave the gas boiler on and have it do all the thinking along with honeywell controller. I dont know if the GB will flame out like I think it should when there is 165 to 185 degree water running through. If I could get this info from somewhere it woulld be very helpful.

 

[bigburner]

your idea will work, I would remove the union on the boiler & roll the black pump forward and rotate motor horizontal, then repipe the DHW line back to the same location. [basically bending the pump and DHW line over] then pipe back to the boiler and this gives you room for the double tee's from Wood boiler. This set up probability won't hold off the GB boiler, unless the wood water is very hot. If the black pump comes on with any call for heat which it should [low mass boiler] Then you may be able to put an aqua- sat on the wood water line, in parallel with the boiler aqua-sat and set the gas boiler lower then wood boiler. 1st stage wood boiler, if water cools off, then 2nd stage gas boiler.

 

[huffdawg]

your idea will work, I would remove the union on the boiler & roll the black pump forward and rotate motor horizontal, then repipe the DHW line back to the same location. [basically bending the pump and DHW line over] then pipe back to the boiler and this gives you room for the double tee's from Wood boiler. This set up probability won't hold off the GB boiler, unless the wood water is very hot. If the black pump comes on with any call for heat which it should [low mass boiler] Then you may be able to put an aqua- sat on the wood water line, in parallel with the boiler aqua-sat and set the gas boiler lower then wood boiler. 1st stage wood boiler, if water cools off, then 2nd stage gas boiler.

Im not understanding what your saying BB is there anyway you could draw it for me.

Thanx Huff

 

[bigburner]

just trying to make the re pipe less of a hassle. instead of lowering the pump, just roll toward you, but that will put the pump with the motor down so you need to rotate it so the motor is horizontal. You wood be looking at the end of the pump, now you look at the side of the pump. then you can hook the DHW to the exact spot there is was originally with a couple elbows. Now just pipe from the end of the pump back to the boiler, somewhere between the pump and boiler add the double tee;s for the wood boiler. Just stare at it, will come to you. You are plumbing out not down.

 

[huffdawg]

What your saying is to cut the pipe above the DHW return to boiler. Also cut the copper pipe on the horizontal between the red and blue valves loosen the union down to the right of the blue valve and undo the Dhw return union.

Then pull the top of the pump down till its horizontal, then rotate the pump upwards till the dhw fitting is facing upwards.(wouldnt that meanhaving to resweat bothends of the pump flanges. and then plumb back to the boiler and DHW return