Where do you find these evacuated tube collectors for sale? It is a pity copper is so expensive, since I really haven’t the skill or ability to deal with aluminum. I could find someone who can, but then I don’t know what that would cost.
We would be interested in an eventual solar component to our setup, not because we risk ever running out of wood, but because anything that makes our time and labor go further may be well justified. We try to grow our own food, and in general provide for most of our daily needs from this property, so a one-time project like solar collectors would be worthwhile if there was a recurrent savings in work for the future.
Although I can picture nofossil’s collector box, I am not sure what the collector surface looks like. How are the tubes formed into the sheet? I am imagining they are a similar layout to Eric’s assembly (that’s a fine piece of work by the way), overlaying the sheet, but I am not sure that is correct.
To get below the Garn storage tank much would require laying the collector nearly flat on the ground, which would presumably lower it by only so much as the Garn is tall. Perhaps this would be enough.
Another comment on solar panels and themosiphoning:
If your hot water needs are anywhere near as modest as your heating needs, it may be worthwhile thinking about another approach. Could you install a hot water tank adjacent to but higher than the Garn? It could then be heated from the Garn via convection, and it would give you more leeway on solar panel positioning. A smaller tank will also give you usable hot water much more quickly and more often, and could have its own backup heat source.
For instance, a 120 gallon hot water tank heated to 120 degrees is much more useful than a 2000 gallon tank heated to 95 degrees. If that smaller tank were heated with oil, electricity, or propane as a backup heat source, then you’d have hot water all the time while taking advantage of each heat source automatically.
Here’s just one online source for evacuated solar panels that includes pricing. I think if you’re serious about solar, you should begin a thread in the Green Room forum. There are a couple of people who hang around there who have quite a bit of experience with solar and some pretty good ideas. Not that I disagree with anything nofossil has said (so far). If you have a gasification boiler, it seems to me, solar is less of a practical decision and more of a philosophical commitment to alternative energy, if that makes sense. In my case, it would be one more thing to play with.
BTW, my parents recently bought a house in a city near their tree farm so that they can spend the harshest part of the Wisconsin winters in civilized surroundings. The house has a couple of huge solar collectors on the roof, and my dad reports that on cold, sunny days (i.e., below freezing) the house stays at 70 degrees without any help from the furnace. Imagine the impact on the energy/pollution equation if every house had a system like that.
Since this solar project will probably remain an experiment for a while, nofossil’s pool heater appeals to me as an inexpensive way to begin trying things out. After the boiler room is built I will see about setting up one of those just outside the building.
Meanwhile, is there a consensus on the best way to insulate the PEX lines between an outdoor boiler room and the house? Or does everyone buy the pre-insulated corrugated product?
There are many ways to do it, ranging from total DIY arrangements to turn-key systems ready to drop into the ground. My piping all runs through building space, so I don’t have any experience with buried pipe.
You might want to start a new thread with a descriptive title and see who drops in.
Father John - Nice looking project! The pre-insulated corrugated stuff looked a little questionable to me so I used a product called Logstor you can see some info about it at Cozyheat.net. On the other hand I am in northern Illinois where the ground is frozen much deeper than your location so it may not be worth the additional costs.
Thanks for the info and name of Logstor. Even though our climate is milder, we have the same risk of getting moisture in the lines, ruining the insulation. If I can’t find a product like Logstor we can afford, I may have to insulate my own lines and install inside some of the PVC we have leftover from our project.
MAYBE
lay the lines
insulate the lines with bubblewrap . i would fold the wrap so that apiece laid parallel with &under;the tubing would fold up & wrap around the tubing. tape it so it holds long enough to place a piece of pvc pipe cut lengthwise,in half,on top of the tubing.i am not savvy as to the chemical inter action between bubblewrap & can expanding foam but it would be great,i think, if you could apply foam to the inside of the 1/2 pvc before placing atop foam.
just an idea....good luck
A couple of days ago I got the first couple of block courses laid, and was able to rake out the gravel for the slab in the new Garn boiler room. I had to spend an inordinate amount of time moving our generator, tearing up the concrete pad, and rerouting all the conduits, but it was necessary to make sure the floor in the boiler room is all the same level.
Today I worked on building the leads and corners, and hope to get many more block laid tomorrow. Since I will be using 1 1/2” Pex, which I think will be too stiff to bend up and keep near the inside wall, I am making a well in the floor, at the end of the trench, so I can always get to the Pex fittings.
When the Pex arrives next week the fun of threading it through the carrier pipe can begin.
I found pex-al-pex, which is stiff like soft copper, to be a lot easier to work with than I expected. You can’t make tight turns without expensive fittings, but it will snake where you want it to go and it’s easy to pull long distances.
The standard required bending rate of normal pex is 6 times the outside diameter (nominal size plus +1/8") of the tubing. So if you figure 7 times you should be safe. For example 1’ pipe equals 6 3/4 Radii on the actual chart. There are some brands that claim better rates but this is the standard all are supposed to meet.
A couple of thoughts when pulling pipe thru another pipe gained from 20 years of trial and error.
Pull all inner pipes together that reside in a single tube and pull all like sizes if possible.
If you need some AC or controll wires pull them in a seperate tube. The black plastic “utility” pipe sold at most lumber yards works well for this as long as it’s allowed by local code. (Well even if not allowed it still works well)
Pulling lube is your pal !!!!
Sold in the electrical section use lots of it if you have a number of bends in your run and just because it seems ok to start with does not mean you won’t wish you had put more lube on that first 50 feet when you hit those bends 100’ later.
For the larger pex pipe and or longer runs consider using a pulling sleeve or whip This is a wire mesh sleeve several inches long open on one end to insert the pipe and connected to a stranded cable loop on the other end to connect your pull rope as you pull the mesh tightens down on the cable or pipe so you can pull with alot of force like a come-a-long or a truck and have a secure connection that slides easily thru the pipe.
It’s a good idea to leave a well even if you don’t need any connections there you might need a pull point or “hand hole” to assist the pipe thru that area.
It has been taking me a good while to get the block walls laid for the new Garn room, especially since the weather has been back and forth this last month. It is hard to get a good solid week of outside work in this time of year. Still, there are just three block courses left to go before I can pour the bond beam and frame the roof.
At the same time I took advantage of a comfortable day last week to insulate the 1 1/2” Rehau pex lines to connect the Garn to the current boiler loop. I used Imcolock insulation with a 1” thick wall, kindly provided by our friends at Nomaco. Since I was working alone I had to come up with a way to control the 100 ft long lines so I could slip the black corrugated carrier pipe over them. I accomplished this by taping one end of the insulated pex to a fence post, then I attached the pull rope (which I previously had slipped through the corrugated pipe with a fish tape) to the other end of the pex. Then I tied the free end of the rope to a tree after pulling tight. The corrugated pipe easily slipped down the taut rope and over the pex. The assembly was then dropped into the trench and shoved through the holes in the walls at each end.
The Garn is due to arrive any day this week, so I really better hurry with the block.
Father John - The pipe solution looks nice, I take it from the picture the feed and return pipes are each in a different sleeve. That looks like a very nice clean and reasonable solution. I and some of the others around here would love some part numbers and estimated costs if you get some time. The installation seems to take longer than expected I am in the about same spot except I have the boiler in place and just got the shed built and the pipe buried. Just started working on the plumbing layout and connections. Nice to see your progress, just like me you will have heat in time for summer.
I see room in the pipe for some foil/bubble wrap too. Can’t have to much insulation. High E did this same principle with foam sleeve first then a couple wraps of 2’ wide foil/bubble.
I didn’t give a list of costs, since our project is quite unusual. We have been able to call upon help from friends at Nomaco in the past, so the Imcolock was free. The Rehau pex was also free, again thanks to some very generous friends who have helped out many time before in our project. I do know what this would cost if all products were purchased, and I still would have been able to assemble the needed materials and install for less than a quarter of the usual price for the different pre-insulated brands go for.
The supply and return lines are each in separate sleeves, and the ends are sealed with PUR foam, so are completely waterproof with no air movement. The polyolefin insulation we used gives us an R-value of about 6. Without a consistent air gap I figured the foil radiant barrier wouldn’t be worth the effort.
Even though I was not looking forward to messing with big pex and pulling it through the carrier pipe, that turned out to be the easiest part of the job. Cutting the hole in the kitchen basement wall was actually the hardest work, since we couldn’t afford to hire a core-drill, and I ended up using our ICS chainsaw to cut a rectangular hole. Spending time deep in a trench with a +100 cc saw burning 25:1 mix left me feeling rather queasy for some time afterwards.
