Masonry heaters

Chris you can get the seasonal benefits by having a roof line that will shade the windows from the high angle sunlight of summer but allow the low angle winter sunlight in. I don’t remember the equation used in passive solar design but it is based on your latitude. I am sure if you google passive solar you can quickly find it or i can look and see if i have any of those design books left. What you describe is very classic 70s passive solar with the south facing windows and the thermal mass the over heating in the summer is a well researched problem with the early designs most everything i read said the correct roof overhang is the best solution. Kind of like why old farm houses have south facing porches to keep the first floor cool in the summer
Unfortunately when i was moving back here to the farm i gave up my dream of building my own home and gave most of my books on home design to a friend who had just bought land and wanted ideas on how to build.

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I would pass the hot air through a box of rocks. The rocks would have a lot of surface area to absorb and release heat from. A box of rocks can be very low cost and easy to make. Maybe black basalt road base rocks that are used by railroads.
Rindert

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Ha! I know well that I come across as the moods-killer asshole.

My needs are wood stove driven whole house dehumidify ventilation.
Me; the three dogs; and at times the two foster girls will go out side in the rain walking and come back wet-wet. This morning accompanied by the three, 5 months old cats too.

Never any talk about the befits of inside house wood heating dehumidifying. Experiencing this it is the real bonus.
I figure we brought in at least 10 pounds of rain water from this morning walk about:


Mine and the girls stuff is not left outside. But brought inside to dry and warm up for the next time going outside. No cold and clammy boots, coats and hats for us!!
Wet dogs and the drying off toweling too needs to dry:

None knows, can smell, our in-house critters. High flow wood stove negative pressurizing ventilation. The wife’s scented candles (count five on the mantel - one lit):

Lots of house plants:




And three free-choice litter boxes for the cats.

Four little girls now, eh Chris?
Lots of going outside wet boots and clothes, I’ll bet.
S.U.

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Referring back to your question #68. There are two serpentine pipe grids in the back of my firebox. That box is two foot by two foot by two foot and is built from welded together 6 inch channel with the flanges turned out. Those flanges are boxed in and I pump air through them with a box fan. That is enough to heat most of the winter living sections of the house without the water if necessary. The steel pipe grid feeds water directly into the two storage tanks and then into the Pex. The whole system was made from obtanium so nothings tech about it. One tank is a full size Oxy bottle and the other is a hundred pound propane tank. I had a metering valve in when I first built it but that proved unnecessary so I deleted it. My water has a high calcium content and every couple of years I have to pull all the piping apart and clean it out. Not a fun job. Had to do it this year. In all these years I have never had a problem with tanks leaking or even deteriorating as far as I can tell. I keep the valve on top of the oxy tank cracked to vent in case I forget to power up the pumps and the water in the tanks gets to boiling temp. Once, years ago, I forgot to open that valve and blew one of the PEX return lines out. That was the only semi-disaster I’ve ever experienced. I guess I should mention that the hot water from the grids thermosyphons into the tanks and I pump the water from there through the floors and it returns colder to the top of the tanks. The main thing about my system is that it must be run hot. I have to refuel it about every three to four hours depending on outside temps. The smoke from the system is generally burned by secondary air into the firebox so much of the volatiles are burned that way but even very hot in the firebox, by the time the heat runs through the convoluted ducting of the smoke path, most of the heat is absorbed in the mass and the heat at the flue seldom exceeds 200f and that flue is 25 foot of 6" sch 40. It had to be brushed out two or three times in the winter or it will clog with creosote. Probably more than you needed to know.

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thermal solar is really only cheaper if you DIY or design it into the house design.

honestly since you are building a new house, I would look at passive solar designs. Not joking.

App State has info including house plans. The planbook goes through some of the design aspects which will help when you go to look at other plans or talk to builders, etc. It is the first 20 pages of the ‘view the entire planbook in pdf’ link from this page (which loaded really slow for me.)

https://energy.appstate.edu/energy-extension-program/online-resource-center/affordable-passive-solar-planbook

There is a good chance, you can get almost all of your heating with passive solar.

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Every BTU pumped out into the open air is a waste. I have put a lot of effort into circumventing that loss. The thing about heating systems and particularly wood fired systems is that a certain amount of heat differential is required between ambient air and the flue of the heater, otherwise the smoke or other gases will not be evacuated. On the Rocket Mass heater in my greenhouse I read over 500f on the surface of the barrel. There is very little if any smoke because it is burned in the tunnel between the fuel feed port and the heat riser. Leave the heat riser at perhaps 800f, travels though ducts inside a heat storage bed filled with cob and exists the flue stack around 80f. If outside ambient gets above 50f then it will require a booster fan to pull the mostly water vapor up the stack. The colder the ambient the better it will work. Closest I have found to a zero waste system. A batch rocket would presumably perform the same but I have not run one to prove that. Under certain circumstances it is also necessary to block off some of the feed port to maintain a good draw plus the fuel has to be refed every half hour or so. Not something a person wants to have to babysit on a daily basis to heat a house.
One of these days I will show the other heater I have built for the greenhouse but it is so far untested. A brief description is a 25 gallon air compressor tank suspended inside a 44 gallon well pressure tank. Inside the compressor tank is a copper coil and between the two tanks is a water jacket. The fuel is fed though the top of the inner tank and heats the water in the jacket and thermosyphon’s up the coil into a 500 gallon open storage tank. I don’t have pictures on this computer or this description would make more sense. The only downside is that the hot smoke and gasses in the burn chamber must be directly vented outside. That’s a lot of lost BTU’s. That upsets me. Because of space limitations, capturing a least a portion of that heat is difficult. With some pictures I’m sure the braniacs here could come up with some solutions. I have to get some taken.

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I think what you are ultimately looking for is called a ‘net-zero’ home. There are a few in NC. But I would also peruse what appears in Northern California that is roughly the same latitude since they changed a bunch of laws recently for new house codes that now actually require like solar and battery storage in their houses which means they will be appearing in house plans that you can buy. There may be some plans that are relatively inexpensive, but in 5 years there will be more which is probably outside your timeline, but it has been worked on for quite a while and the whole net-zero concept has been reappearing for a decade so there are plans that incorporate newer technologies and research. I personally would start there.

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