Stepping into the boiler world but I'm a lost puppy that needs some direction

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CountryBoy19

Minister of Fire
Jul 29, 2010
962
Southern IN
I've been burning EPA high efficiency stoves and ZC fireplaces for almost a decade now. I've been a member just about as long. But boilers are a new world to me and I could use some guidance in how to best set my system up. So if you don't mind, take a look at what I have and tell me how YOU would set it up if it was yours.

I currently have ground-source geothermal heating/cooling and I only plan to supplement home heating with the boiler. IE, if I feel like starting a fire I'll start a fire, if I don't, I won't. House is 5600 square feet but 1200 of that is not conditioned (storage space). It has 2 water-heaters, 1 in the garage, 1 in the utility closet in the house.

What I have:
My dad is giving me his Econoburn boiler. I believe it is an EB-200 but it may be a 150 (can't recall for certain).
With that he has a 200 gal hot-water heater tank he has been using for storage. If I can fit it into my crawlspace I plan to utilize that as well.

What I want to do:
Heat the in-ground swimming pool to extend the swimming season (not a lot, just get it up to comfortable temp a month or so earlier in the spring and maybe keep it at temp a month or so later in the fall).
Heat domestic hot-water any time the boiler is running.
Supplement existing home heating

Critical information:
I do not currently have a good place to house the boiler, I plan to add on a small boiler-room to the garage. Directly behind this boiler room is the pool closet which sits on a crawlspace that I think is large enough to house the 200 gallon storage tank.
The pool pump equipment is approximately 60 feet away from the boiler room and lines could be run underground (would have to be hand-dug) or could be above-ground and exposed to the elements.
The main furnace and hot-water heater are approximately 65 feet from the proposed boiler room, all routing will be through crawlspaces. This run passes through 3 different crawlspaces, through 2 masonry walls. There is a 14 length between the 2 masonry walls (under the floor of the breezeway between the garage and house) that is not accessible. I'm hoping I can core-drill some 5" holes into the masonry walls, then slide a 4" PVC pipe in to make a "conduit" of sorts that will help guide the pipe under that breezeway floor.


Specific questions:
#1 Should I take hot boiler water to a heat exchanger near the pool-pump, or bring pool water to an exchanger in the boiler-room?
#2 I plan to have everything zoned with valves so I can turn heating to the pool, domestic water, and home heating on/off independently. I know how to set up a manifold, but how/where do I incorporate that into my boiler/storage tank plumbing?
#3 What kind of lines do I run to the furnace & hot-water heater? That's a long run to go uninsulated. Do you just buy pex and put that black foam insulation stuff on it? That may be challenging with the "conduit" I plan to push under the breezeway floor. Any thoughts/suggestions?


More musings from me (you can skip this if you already feel like I've written a book):
My envisioned burn style goes like this... as fall temps come and I want to extend swimming season a bit for the kids I'll fire up the boiler. This can heat the pool as needed, heat the domestic hot water, and if necessary for any cold snaps that happen along, at just a little heat to the house without kicking on the geo heating. As temps go down and it's not practical to heat the pool anymore I'll shut that valve off. The freed up BTU's the pool were using will now go to heating the house as needed (still heating domestic hot-water). Burn through winter as I feel like it and definitely burn through cold-snaps when the geo can't keep up. Then in spring, cut back on home heating and start bringing the pool up to temp. As summer approaches the valve for home heating will be shut off and eventually, when weather is warm enough that the pool stays warm the boiler will be shut down. From there we may fire it up occasionally if we get a lot of rain on the cover of the pool it cools it off so we may want the occasional warm-up throughout the summer.
 
Thoughts- I'd run the boiler water to the pool, not pool water to the boiler. With a decent delta T you'll need to move less water.
A 4" PVC pipe should be able to fish two 1" (maybe 1 1/4”) insulated pex pipes through... If it's straight. 90's are miserable.
Definitely insulate your lines.
 
The pool volume will determine that heat load, for example I used to heat a 22kgal gunite pool with a Garn, using a 250 kbtu shell and tube hx, this is was what the propane pool heater was rated at. This was piped in series, through the propane heater, using the thermostat on the propane heater as a limit switch. When the wood temp was higher than the propane thermostat, it was on wood, once it fell below, it would kick the propane on. If I remember the hx was piped 1.5 inch.
This worked well, burned more wood in the summer than to heat the house in the winter. I’m not sure how useful a 200 gal storage tank would be, consider larger to eliminate idling.
 
The pool volume will determine that heat load, for example I used to heat a 22kgal gunite pool with a Garn, using a 250 kbtu shell and tube hx, this is was what the propane pool heater was rated at. This was piped in series, through the propane heater, using the thermostat on the propane heater as a limit switch. When the wood temp was higher than the propane thermostat, it was on wood, once it fell below, it would kick the propane on. If I remember the hx was piped 1.5 inch.
This worked well, burned more wood in the summer than to heat the house in the winter. I’m not sure how useful a 200 gal storage tank would be, consider larger to eliminate idling.
Thankfully our pool stays warm enough the majority of the summer... we're just hoping to get it up to that "warm enough" mark a little earlier in the year and keep it there later in the year.

Do you have thoughts re: burying the pipe over to the pool pump vs running above-ground? Any suggestions on pipe to use or how you would do it?

I planned on making my own shell & tube xchanger but seeing cost is about $1/kBTU (IE, I can get a 150kBTU for about $170) I'm not sure it's worth the effort and all the stainless steel...

200 gallon storage tank is what I have and even that may be too large to fit in the space I have. My problem is that the place I'm adding the boiler-room is restricted on size (I can't make it bigger) and there is no good place to put a storage tank reasonably located in close proximity to the boiler or furnace etc except to place it in that crawl-space I mentioned... I'll have to make-do unless the situation ever changes.
 
I have the same boiler,love it tough and simple.
Try and find space for storage,your 200 gal tank is too small.
If you can foam in trench for your underground lines.
 
Personally I would bury underground if possible, just to keep it protected if nothing else. There are various preinsulated underground pex piping systems out there. Would probably be worth seeing what's available locally due to it being bulky and expensive to ship.
 
Personally I would bury underground if possible, just to keep it protected if nothing else. There are various preinsulated underground pex piping systems out there. Would probably be worth seeing what's available locally due to it being bulky and expensive to ship.
I should have elaborated more on this but I felt like I was already writing a book. The "run" over to the pool pump will be mostly underneath a deck that is about 4 feet off the ground (I can crawl under there to dig a trench but it won't be pleasant). On the contrary, because it's under a deck it will already be somewhat protected even if it's not buried. Although it would still be a good idea to have some sort of hard outer shell to protect it from rodents and such.

Thanks for the good advice. I realize 200 gallons isn't enough for ideal burning but I simply cannot do better than that for the time being. I've considered adding a basement to the house and if I did I could possible build a storage tank in the basement but currently there is no way to get a tank in the crawlspace under the house because the access door is way too small. The door cannot be opened up larger because the exterior of the house is rock so the foundation cannot be altered easily. The house is almost entirely surrounded by concrete driveway/patio etc so burying a tank out in the yard somewhere present logistics problems of getting lines to/from the tank. The only place I could place a tank & route lines would mean my total line length to/from the tank will be over 500 feet which means a LOT of thermal losses.
 
You would need a shell and tube hx, aside from the btu rating also aware that pool water treatment, chlorine or salt requires a different hx. Also on the pool side plumbing sch40 glue joint would work, can it be insulated and hung under the deck?
 
I should have elaborated more on this but I felt like I was already writing a book. The "run" over to the pool pump will be mostly underneath a deck that is about 4 feet off the ground (I can crawl under there to dig a trench but it won't be pleasant). On the contrary, because it's under a deck it will already be somewhat protected even if it's not buried. Although it would still be a good idea to have some sort of hard outer shell to protect it from rodents and such.
Makes sense. I've run insulated lines on top of the ground that way in a conduit, a power outage and freeze-up would be my only concern. Pex won't burst with freezing but getting it moving frozen could be a problem. I don't use glycol all that much but it would be an option.
I'm sure there are other ideas too.
 
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Yeah, you're right. Brain freeze.
 
Makes sense. I've run insulated lines on top of the ground that way in a conduit, a power outage and freeze-up would be my only concern. Pex won't burst with freezing but getting it moving frozen could be a problem. I don't use glycol all that much but it would be an option.
I'm sure there are other ideas too.
By "insulated lines run in a conduit" do you mean you put insulation on pex and shoved them through some conduit, or you bought the pre-made $$$$$ stuff? Just wondering how you did the insulated lines in conduit. I would have to go around a couple bends but if I play my cards right I can possibly get by with two 45-degree angles.
 
Did you read the sticky"Underground lines not the place to skimp"?
 
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By "insulated lines run in a conduit" do you mean you put insulation on pex and shoved them through some conduit, or you bought the pre-made $$$$$ stuff? Just wondering how you did the insulated lines in conduit. I would have to go around a couple bends but if I pl
ay my cards right I can possibly get by with two 45-degree angles.

I would use preinsulated underground pipe, homemade doesn't hold up well. Might have to use wrapped to be able to feed it through. I've run it in a PVC conduit for more protection above ground. Foam filled is better but I wonder if you can realistically fish it through as it's a good bit stiffer. I'm just guessing as I haven't seen it.
 
Did you read the sticky"Underground lines not the place to skimp"?
I have but I'm not sure that's entirely applicable to my situation. The only outdoor run I have will be to the pool which will only be used during warmer temps (the concern for r-value isn't as bad because the temp differential isn't as big) and I'm not sure how the logistics of digging a trench that big under a deck that I have to crawl under is going to work, let alone the process of foaming it etc... That being said, I'm open to suggestions as to how that can be applied to my specific situation. That's why I'm asking questions.
 
I've run a fair amount of the preinsulated pex piping from Badger in crawl spaces to cut heat loss, much neater and doesn't get brittle like the black clip on insulation does sometimes.
Just my experience with outdoor wood boilers, I'll let other guys take this further as I haven't worked with indoor boilers with storage.
 
If it was me i would still do the spray foam...
If your lines aren't underground build a PWF wood chase and foam the lines in the chase.The only way to overcome lost BTU's in your lines is to burn more wood,dosn't matter what time of year it is.
 
The only way to overcome lost BTU's in your lines is to burn more wood,dosn't matter what time of year it is.
I understand that the only way to overcome BTU-loss is to add more BTU's. But I don't think you're following what I'm saying. A number of things contribute to the amount of BTU-loss. While time of year may not matter for buried lines (because the ground stays the same year-round), it does matter for an above-ground line. BTU-loss is a function of R-value (not just of the insulation but also of the convection/conduction to the external medium) AND temperature differential between the liquid in the lines and the external medium outside the lines.

In this case we're comparing 190 degree water to 70 air (natural convection to the air) to 190 degree water and 50-degree moist soil (conduction directly to the soil). The temperature difference is only marginally better, but the natural convection to air vs conduction to moist soil is what really makes a big difference. Throw in the fact that this line will only be on when the pull pump is on (about 4 hrs/day)

The BTU-loss on a line run in a duct, exposed only to air with an average temp of 70 degrees, and run only 4 hrs per day is going to be a fraction of the BTU loss of a buried line in direct contact with the ground, on a boiler running 24/7 in the winter. That's the point I'm making. I'm not trying to skimp, just not trying to overkill it (and kill myself in the process by digging a deep trench under a deck).
 
I wasn't advocating to dig a ditch just to foam the lines.
In your case i would build a wooden plywood chase above ground out of treated plywood and have the lines foamed in the chase.
It dosn't mater if the lines are above or below ground,i would still insulate them with spray foam.It probably wouldn't be much difference in price between buying insulated lines and getting lines spray foamed.