Econoburn 150 install

[Zeppy]

Hello everybody,
So, I have had the blue beast sitting in my basement for over a year. It's probably time to get it installed. Here is my situation. I currently have an oil boiler with domestic coil. My house is basically in two halves (no not three halves) Each half has 600sqft on each floor (basement, 1st floor and 2nd floor) Basement is half in slab radiant and half modine unit. 1st floor is all staple up radiant. 2nd floor is half staple up and half baseboard. The half that is baseboard rarely calls for heat. I have a 500gal lp tank for storage
My currently thinking is to plumb the EB150 in series with the ob and utilize the existing domestic coil. It seems like most of the diagrams I've seen plumb the two boilers parallel. (Am I understanding this correctly - Parallel would maintain the ob cold until it was needed and series would maintain the ob at operating temp.) What are the cons of series plumbing? I would like to avoid an indirect dhw heater if it is feasible. Once I get a basic strategy I would like to bug you guys about some more specific plumbing questions.

Thank you in advance for your input

Travis

 

[Clarkbug]

Travis,

The big con of hooking up in series is that you have a lot of heat loss through the oil boiler when its not running. With that atmospheric flue, it will just pull heat right up your chimney all of the time, and that really can cut into your efficiency.

There are a few threads on that here in the forum, grab a cup of coffee and do some searching/reading when you get a chance. Im sure other folks can get much more technical than I can about it.

 

[dougcarlo]

I wonder if a person could put a automatic damper opener on? When the oil boiler starts it opens a damper or something?

 

[Zeppy]

I just read a post from July that kinda addresses a couple of issues. There is a link to an automatic damper to lessen the losses up the chimney. There is also a comment regarding the amount lost versus increased plumbing and controls cost. If I plumb parallel then I need to get a superstor which I'm told is somewhere north of $1200.00.
What additional issues arise when plumbing in series and using 500gal storage. I have read that some guys allow their ob to heat storage. I hadn't considered this previously because I didn't think it made sense to use the ob to heat storage but I seems like it really simplifies the system and my grand plan is to not burn oil anyway. I would also be concerned that if I let the storage get too low then I need to heat all 500gal before I have anything usable. I don't think I understand how this would work with a domestic coil in the ob. Seems like it would be difficult to use the storage for dhw especially in the off season.

I am starting to think that I should go back to my original plan which was Parallel with indirect dhw.....

Expansion tank: I know this has been beaten to death on this forum but..... my installer has said that I need to have an expansion tank equal to 30% of system capacity. This seems excessive and I think I have read that 10% is more than enough.

Travis

 

[pybyr]

Return temperature protection/ management is essential to efficient operation and longevity of your EB, and unless the EB manual has come a long ways since I saw the latest version (and it's entirely possible that the manual may have come a long ways), is not particularly well-covered in the manual.

I'd never use a fossil fueled boiler to heat storage. Storage's one advantage is with/ for heat sources that you can't effectively turn on and off at the times you do and don't need heat (wood, sun). For sources that you can turn on and off, the best place to store the energy is in the fuel; every time you convert or move energy, you're going to lose substantial amounts along the way; that's basic laws of thermodynamics.

 

[Singed Eyebrows]

.. my installer has said that I need to have an expansion tank equal to 30% of system capacity. This seems excessive and I think I have read that 10% is more than enough.

Travis

Your installer probably doesn't want to see pressure rise much. My Atmos is supposed to be run with a large tank like that, they call it "pressure balancing". I would listen to your installer, Randy

 

[Zeppy]

Thanks for that info Randy. I was ready to "discuss" it with him but I guess I will let it go. I'm not real excited about paying for 180gallons of pressure tank(s) though.

 

[willworkforwood]

I just read a post from July that kinda addresses a couple of issues. There is a link to an automatic damper to lessen the losses up the chimney. There is also a comment regarding the amount lost versus increased plumbing and controls cost.
I was the one who made that comment, but the context was for reworking an existing in-series, no-storage system. You are installing from scratch, so the net cost may actually not be more for parallel.
If I plumb parallel then I need to get a superstor which I'm told is somewhere north of $1200.00.
I think you can find alternatives to the SS - a sidearm, or perhaps a less expensive HW heater/tank.
What additional issues arise when plumbing in series and using 500gal storage. I have read that some guys allow their ob to heat storage.
I hadn't considered this previously because I didn't think it made sense to use the ob to heat storage but I seems like it really simplifies the system and my grand plan is to not burn oil anyway.
As Trevor said above, heating storage with fossil doesn't make sense - they operate on-demand.
I would also be concerned that if I let the storage get too low then I need to heat all 500gal before I have anything usable.
The system should be piped and controlled to bypass heating storage if there is a call for heat that can't be satisfied by storage - Some (or all) of the heat from the boiler would go directly to the zone(s) until they are no longer calling.
I don't think I understand how this would work with a domestic coil in the ob. Seems like it would be difficult to use the storage for dhw especially in the off season.
Only a few folks on this forum run their boiler for DHW in the Summer - most of us are happy to take a break. Solar DHW in the Summer is the way to go.
I am starting to think that I should go back to my original plan which was Parallel with indirect dhw.....
Expansion tank: I know this has been beaten to death on this forum but..... my installer has said that I need to have an expansion tank equal to 30% of system capacity. This seems excessive and I think I have read that 10% is more than enough.
Is this the same installer who recommended that you shouldn't use storage at all ? :bug:
You should put together a system diagram and post it here for the hydronics gurus to review and offer advice.

 

[Zeppy]

Willwork,
Thanks for the input. Yep same guy that did NOT recommend storage. Unfortunately he is the 4th installer I have spoken with and he is the only one that has installed pressurized storage(just doesn't recommend it). I'm going to do my best to come up with a diagram to post for scrutiny.

 

[ewdudley]

Hello everybody,
So, I have had the blue beast sitting in my basement for over a year. It's probably time to get it installed.

I have a 500gal lp tank for storage

My currently thinking is to plumb the EB150 in series with the ob and utilize the existing domestic coil.

It seems like most of the diagrams I've seen plumb the two boilers parallel. (Am I understanding this correctly - Parallel would maintain the ob cold until it was needed and series would maintain the ob at operating temp.)

What are the cons of series plumbing? I would like to avoid an indirect dhw heater if it is feasible.

One way of avoiding an indirect DHW unit on its own zone is to move the tankless coil from the OB into the top of your storage tank:

https://www.hearth.com/econtent/index.php/forums/viewthread/72019/#835793

No sidearm, no DHW zone, no DHW zone pump, and no mixing and destratification of storage due to excess flow through an indirect DHW zone. Just move the coil out of the boiler and put a gasket and plate over the hole in the boiler.

When using a fossil fuel boiler plumbed in parallel as your heat source, it can be used to heat the top of storage, and thus DHW as well, which works quite well for me. This makes the top of storage a buffer tank of a couple dozen gallon capacity and nicely eliminates short cycling of the fossil fuel boiler, hand-waving about thermodynamics notwithstanding. However it then becomes necessary to provide return temperature protection for the fossil fuel boiler as well as the wood boiler.

my installer has said that I need to have an expansion tank equal to 30% of system capacity. This seems excessive and I think I have read that 10% is more than enough.

The size of the expansion tank you need is pretty straightforward to determine by any competent installer given the size of your system, the elevation of the components, and the maximum working pressure of your boiler.

It doesn't sound like you installer is doing his homework and is trying cover his butt at your expense. Ten percent is typically more than enough and can be relied upon until your installer can come up with an analysis of your system that would show different.

 

[willworkforwood]

Travis,
In coming up with your system layout, be aware that Econoburn now recommends (for many, if not all) systems using storage, that the supplied 007 pump for the near loop should be replaced by return protection via a mixing valve instead. The 007/near loop works well for systems without storage like mine, but the large dose of cold water return from big storage tanks doesn't get properly taken care of by the pump. Now, this comes solely from what I've read on the forum, so you should check with Dale at the Econoburn factory for the latest update and recommendation on this subject.
EWD, That's a slick way of handling your DHW. But I'm guessing it requires above-average knowledge, or a willingness to learn, in order to make it function efficiently. Do you think the installer that Travis is working with would be able to successfully implement something like what you did?

 

[Zeppy]

Willwork,
Dale did confirm that I need a mixing valve.


EWD,
If I'm understanding this correctly, then I will need to cut a fairly large hole in my 500gal lp tank to install the coil.

 

[ewdudley]

Travis,
EWD, That's a slick way of handling your DHW. But I'm guessing it requires above-average knowledge, or a willingness to learn, in order to make it function efficiently. Do you think the installer that Travis is working with would be able to successfully implement something like what you did?

It's pretty easy to control, there is thermowell near the top of the tank and somewhat below the top of the DHW tankless coil that provides a call-for-heat to the fossil fuel boiler. This call-for-heat signal is in series with another aquastat that senses temperature at a point in the tank below the bottom of the DHW tankless coil, all of which latches a relay until the lower aquastat drops-out.

When the wood boiler is on-line and until storage is depleted, the fossil fuel boiler stays off, but when storage runs out the top aquastat kicks the boiler on, and it runs until the lower aquastat turns it off.

The fossil fuel boiler only runs enough to keep the house warm and to supply DHW, it doesn't try to fill storage except for fifty gallons or so at the top, which is nice for eliminating short-cycling of the fossil fuel boiler.

Willwork,

If I'm understanding this correctly, then I will need to cut a fairly large hole in my 500gal lp tank to install the coil.

The boiler tankless coils I've run across all have a standard 4" ID neck with a six-bolt flange. I bought a neck and flange from a boiler manufacturer and then went ahead and cut approximately the right size hole in the top of my tank with a torch and dressed it out with a sawzall and file and contoured the neck with a grinder until it all fit up well enough to weld.

Then I put it on a trailer and took it to a pressure-vessel certified welder to run the beads. He did it on the trailer in his shop driveway with and AC welder and 6011 stick. I'm like what, no MIG? and he mumbled something about watching the puddle. He did a great job much better and faster than I could have.

Or you could spring for one of those Vedolux tanks with the coil already in it and then add a propane tank for extra storage, which would save a lot of logistics and messing around. I believe the Vedolux tank has an internal water flue that guides the cooled water away from the DHW coil down to the bottom of the tank, which would be more ideal.

 

[b33p3r]

Travis, I hooked my EB-150 up last year. I had the situation as you are encountering. I ran my Eb in series with the OB. Not because it was the best way to do it, but because it was the cheapest way for me to get up and running. Basically the supply from the wood boiler flows through the Oil boiler and returns back to the wood boiler. By doing it this way it also maintains my DHW. It worked out fine for me. I did add a relay that gets activated by the primary pump of the wood boiler and keeps the oil boiler from firing on as long as the WB is circulating to the house. Other wise my oil boiler would be firing on every time the water temp got below 180*. But also if my fire ever went out(temp below 150*), the oil boiler would be able to kick on again.
As far as losses up the OB chimney, I'm sure there are some but the cap of the chimney kept snow on it all winter long?
My intent is to eventually install storage. Just not there yet.
Beeper

 

[2.beans]

i don't recall reading any statistics on how much more wood anyone has burned by hooking their wood boiler to existing system in series. also if its more expensive and time consuming to hook up wouldn't that overweight the extra wheel barrel load of wood that you'd save.

 

[henfruit]

If you run a cold oil boiler then let it get hot then cold agin you are looking for trouble as the sections may develope a leak fron all the expantion and contraction.

 

[b33p3r]

2.beans...For me the series connection was a no brainer($$$) With my DHW coil incorporated in my boiler, it would have cost alot of extra bucks for an indirect tank. I ran last winter in series and I had no problem with it. Like anything else..if you never had it you don't miss it. I never had water storage so I don't miss it. However I will eventually graduate into storage and I'm sure after I have it I won't want to do without it.

Henfruit......My oil boiler never gets below 150*. Since the wood boiler is in series with the oil boiler, the wood boiler keeps the oil boiler at a minimum of 150*. From what I've read the magic number is 140*? Anyone is welcome to tell me I'm wrong. I'm always willing to learn new info. So when my wood boiler gets below 150*(thus the oil boiler gets below 150*) , the oil boiler is allowed to fire again thus the temp never goes below 140*.

 

[2.beans]

[quote author="b33p3r" date="1316368650"]2.beans...For me the series connection was a no brainer($$$) With my DHW coil incorporated in my boiler, it would have cost alot of extra bucks for an indirect tank. I ran last winter in series and I had no problem with it. Like anything else..if you never had it you don't miss it. I never had water storage so I don't miss it. However I will eventually graduate into storage and I'm sure after I have it I won't want to do without it.






i agree. im saying i dont know if anyone has any numbers as it being that big of a wood savings. if it costs you a $1000 to saves one wheel barrel of wood a year i dont feel that the extra money is worth it. 2.beans

 

[heaterman]

i don't recall reading any statistics on how much more wood anyone has burned by hooking their wood boiler to existing system in series. also if its more expensive and time consuming to hook up wouldn't that overweight the extra wheel barrel load of wood that you'd save.

And there you have it. Keep it simple. Simple is good.

Frankly, I never get to shook up about boilers in series for a few reasons.
1. Does the cost of "wasted" heat going up the chimney justify the expenditure and added complexity required to prevent it?
2. That wasted heat is actually keeping the chimney and the fossil fuel unit dry and free from condensation. (A good thing)
3. If the boiler in question is a modern design, it probably has a draft blower or maybe even a concentric venting setup which greatly minimizes the heat loss in the first place.
4. What does it really cost, seriously, in terms of additional pounds of wood burned annually?

 

[henfruit]

I have mine set at 130. When the boiler gets below that temp the pump kicks in to get back to 130.If the water temp in the storage gets below 130 the oil boiler take over to make the heat.

 

[Zeppy]

Thanks for the feed back, especially because it is what I wanted to hear! My installer got back to me this weekend with a price for parallel with indirect, I nearly listed the EB150 on craigslist right then but I was under the influence of wisdom teeth removal so decided to hold off.
It really sounds like the only draw back to series is some lost heat up the chimney. With the benefit of 1)Simplified system 2)Less expensive install 3)Less detrimental to oil boiler 4)perhaps some benefit to the chimney

Thanks again for the input.

 

[b33p3r]

I have bought 150 gallons of oil in the last 11 months. I purchased that to keep me into DWH when I wasn't burning wood. I peeked in the oil tanks 2 days ago and I will not need to buy anymore oil this year.(Unless the price bottoms out..I know that's funny!). I will probably buy some in April/May 2012. I typically bought 900-1000 gallons a year. You figure it out. Hook it up in series for now and build on it later if "YOU" choose to.
Now that I think about it I can probably lose 1 of my 2 tanks and give myself more room in my basement...Hmmmm!