Win a copy of Building Community this week in the City Repair forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education skip experiences global resources cider press projects digital market permies.com private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nicole Alderman
  • paul wheaton
  • Anne Miller
  • Pearl Sutton
  • Mike Haasl
  • Joylynn Hardesty
stewards:
  • r ranson
  • James Freyr
  • Burra Maluca
master gardeners:
  • Steve Thorn
  • Greg Martin
gardeners:
  • Ash Jackson
  • thomas rubino
  • Carla Burke

! the first wofati - allerton abbey- version 0.7

 
Posts: 72
24
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Fabulous. Is there a way to graph when heat was applied and for how long?
 
master steward
Posts: 31938
Location: missoula, montana (zone 4)
hugelkultur trees chicken wofati bee woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

Tim Skufca wrote:Fabulous. Is there a way to graph when heat was applied and for how long?



I think the really important information will come from the ten days of no fire.

 
Tim Skufca
Posts: 72
24
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The rise in interior temps doesn't seem to always correspond to the rise in outside temps which would indicate there was a fire built inside. Any way to know when a fire was built?
 
Tim Skufca
Posts: 72
24
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
this data is great - what "contraptions" did you buy?
 
paul wheaton
master steward
Posts: 31938
Location: missoula, montana (zone 4)
hugelkultur trees chicken wofati bee woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

Tim Skufca wrote:this data is great - what "contraptions" did you buy?



http://amzn.com/B00074UZ4A

 
pollinator
Posts: 1481
Location: Vancouver Island
53
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

paul wheaton wrote:Daniel and Sharla had me buy these two thermometer contraptions.

Here are the results of starting to run fires inside, including getting it to 85 for the first time.



I put some comments There:
https://permies.com/forums/posts/list/560/45960#423258
That really could have gone here.
 
paul wheaton
master steward
Posts: 31938
Location: missoula, montana (zone 4)
hugelkultur trees chicken wofati bee woodworking
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I just had an hour long talk with evan and sharla.

I think we need to shore up the insulation layers on the uphill and downhill sides and try again.

On the downhill side there is a hole in the wall to allow electrical cords to pass through. There is debate over whether is it currently plugged or not.

Both of the doors have no latches and leak around the edges. I would really like to find somebody with excellent woodworking skills to come and craft excellent latches for the doors and excellent wool-based weather stripping.

Sharla thinks there could be a lot of other micro leaks in the walls, especially the not-yet-cobbed uphill wall. She is going to search for gaps and fill them with wool.

And then there is the rocket heater. You cannot close the feed with a couple of bricks like you can with j-tube system - so that would be a place where air could continue to move through and out. Even more is the duct near the wall. It is 8 inch duct. When there is no fire, it acts as a rather significant heat exchange. Maybe it would be wise that when we choose to start the test, we dismantle the exhaust and plug it with wool for the duration of the test.

The glass is very cooling. We are talking about possibly adding something like storm windows, plus window quilts.

Evan has been making sure to get it up to 85 each day and 85 is very uncomfortable. So we are thinking that it might be better to get it up to 80 a few times a day.

---

The plan:

61) Add oodles of wool

62) Take a video of the doors and windows, trying to get as much detail as possible. Maybe somebody can come up with some really excellent plans for each, and then come here very soon to implement those plans.

63) We're gonna buy more firewood (yes, we could harvest our own, but right now I want the little bit of labor we have here focusing on permaculture stuff instead).

64) Make a plan for complete disconnect of the rocket heater exhaust when the time is right - and thoroughly plugging it.

65) Come up with a thorough plan for all glass to add "storm windows" PLUS window quilts.


Anybody have anything else to add to this plan? Anything we might possibly be overlooking?

Most of all, I would very much like to have somebody come by soon who has amazing superpowers in the world of woodworking. Somebody who can do amazing things with our windows and doors.

 
pollinator
Posts: 1462
Location: Victoria BC
198
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I'd kinda expect that a well insulated plug inserted into the feed and into the exhaust would be sufficient to very greatly decrease losses through the rocket system when it's not running, without the hassle factor of any disassembly/reassembly? This could be 'T' shaped so that insulating material matching the diameter of the tube goes inside, and then overlaps the orifice on the outside; anchor points outside the orifice would allow the plug to be cranked down a bit to provide a good seal. Making the orifice and plug slightly tapered would allow an even better seal...


As I see it, in a mass-rich structure like this, the purpose of the RMH is to heat the mass, so that the mass can provide a nice air temperature for the occupants. Overheating the air while striving to put more heat into the mass seems like a hint that less thermal transfer to the air inside is desirable; more of that heat needs to go into the mass directly. So, how does one design a RMH to do that? Can you just bury more of it in cob? I've seen old gas stoves which run 24/7 which use large insulated covers over the top burners; maybe something like that could be designed for a RMH? Unreasonably elaborate heat-exchanger systems to capture heat off the barrel and transfer it underground?

Or, to take a different approach, having the RMH in an area that can be closed off from the rest of the living space could allow more pleasant temps in the other portion.


Not likely of immediate use, but a narrow enclosed porch/glasshouse on each side could help out on the window insulation front without cutting off winter light. It would have the added advantage of serving as an airlock setup, so that less heat would be lost when the doors open. Wood could be stockpiled in this space, as it currently is under the eaves, cutting down on the need to open the outer door. Even doing this on only one side, this side could be used as the primary access, to get the airlock benefit. The other door could receive extra insulation in the form of hung blankets that would be in the if it was used frequently.


It would be interesting to know the temperature inside the mass at various depths; maybe in future builds sensors could be placed during construction?


Really enjoying the testing updates, thanks everyone!
 
Tim Skufca
Posts: 72
24
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I certainly appreciate the purist approach to all elements in the WOFATI, but spending so much energy to use natural materials to weatherstrip the doors might be a bit silly. [every window in there has some sort of petroleum product in it] Using off-the-shelf weatherstripping and threshold to seal the doors seems to make sense. It won't require a master craftsman to install it. Pick up a couple used door knobs at HomeReSource to get a tight fit and you've seriously helped the situation.
 
Len Ovens
pollinator
Posts: 1481
Location: Vancouver Island
53
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

Dillon Nichols wrote:
As I see it, in a mass-rich structure like this, the purpose of the RMH is to heat the mass, so that the mass can provide a nice air temperature for the occupants.



No, That is not correct. The purpose of mass is not to heat the air inside, but to heat the occupants. It is true heating the air is part of that, but to keep the occupants comfortable, the air temperature can be much less than in a non-mass home (or should be able to be less ). A good part of the comfort should come from heat radiated from the mass too. In the case of heated mass, direct contact of the body with the mass is also important. Cob furniture for example may help. The thing to remember too, is that the RMH, great as it is, puts out a lot less heat that the ground collects in a summer under the sun.


Overheating the air while striving to put more heat into the mass seems like a hint that less thermal transfer to the air inside is desirable; more of that heat needs to go into the mass directly. So, how does one design a RMH to do that?



Shorter barrel for one. The RMH in this wafati was designed to heat people not mass. However, that is what is there. Heating the air to heat the mass is not the greatest way of doing things, but it is enough to see what effect added heat might have. What I am seeing is that this is a huge piece of mass. It will take a lot of heat to bring it up to temperature... right now most of that mass is acting as a heat sink. In future it will radiate instead.

I am thinking this:
1) ground prep... dig the foundation out early spring. Cover with a tarp at least when raining. Let it soak in the sun heating the earth mass under. In the fall when the temperature of the earth is no longer able to rise or the rain is making things difficult, cover with tarp, cover tarp with straw bales, cover bales with another layer of tarp. Leave it for the winter. The tarp should be the same size as the outer limits the mass umbrella will end up being.

2) mass prep... all that earth dug out to make foundation should be spread out close by and treated the same as the foundation to soak up as much heat as possible. The thinner it can be spread during the summer the better... 6 inches or so would be nice. For the winter it should be repiled if possible before tarp and bales are added for best heat retention.

Next spring: Depending on the temperature under the lower tarp, start building early in the spring or cycle through another year of letting the earth soak up sun. A long temp probe that can read temperature 6 feet down would be nice. (deeper would be nicer) In an experimental situation, permanent temp probes at various depths would be really nice... but do cost.

3) build: This should start early spring as soon as snow or rain are not an issue. At night cover the ground with tarp and bales and tarp if at all possible. Certainly a tarp to keep any rain out should be a must. If possible leave the downhill side of the earth next to the building bare the whole summer (cover at night if possible) and add the umbrella in the fall.

4) for the next winter instead of finished the umbrella off on the downhill side, use the bales and tarp for another year. This will allow the lower tarp to be lifted for another summer of heat gathering if needed on that side of the house.

I think this would precharge the mass as best possible. The more lead time the better. The tarp/bales/tarp just left for a number of years if you have the lead time may do the job in a more passive way. It would also (with proper monitoring) help decide how big the umbrella needs to be without lifting a shovel.


Or, to take a different approach, having the RMH in an area that can be closed off from the rest of the living space could allow more pleasant temps in the other portion.



I think heating the mass is more important than comfort at this point. If comfort was an issue, that could be a plan though.
 
What's a year in metric? Do you know this metric stuff tiny ad?
Learn Permaculture through a little hard work
https://wheaton-labs.com/bootcamp
reply
    Bookmark Topic Watch Topic
  • New Topic