Rudy Mallonee

Hello Paul

For zero impact on fish --- plus aerating the water--- and if you can do the labor, it can be a fairly inexpensive hydro system that needs no more than a meter of fall for 14KW of power, or more depending on size of your system...
www.zotloeteter.com

Allen,
I'm not expressing myself very well !! And just trying to see if my idea has merit. Have been thinking of how to keep it simple for heating a larger home with a rocket stove.. This is as simple as I have come up with so far...

But yes,essentially, you've got it right........ Get a good air to air exchanger from a used forced air furnace..The " labrynth of sheet metal after the burn chamber" as John Master calls it - is simply an air to air exchanger.... . Don't have to build one as there are a lot of used ones on the market, here in Alaska, anyway (Craigslist, etc.) as I had said, from free to a minimal $ amount....

Build your rocket stove... Duct the flow of exhaust gas to heat the air to air exchanger, then the clean heated air goes to the crawl space heat sink (in a presently constructed house that has a crawl space) or in a new house with the crawl space designed into it so that you have an enclosed heat sink there -- which could be a simple insulated concrete block box of sufficient size, filled with rock for the thermal mass -- duct in - duct out to rooms ------ return air duct (ceiling height) is just returned to the exchanger as in a normal forced air system... If there is a "auto feeder to regulate fuel input", as John Master says, then that might solve any problem with over/under heating ??

As John Master wants to keep the stove outside, it would still work in the same way with a boiler unit water heat exchanger.. With a constant, consistent heat source ("auto feeder to regulate fuel input", there shouldn't have to be a need for a heat sink as the amount of water/glycol in the system would be sufficient capacity.. Just plumb the system as you would for a normal radiant hot water in-floor or baseboard system..

Please improve and refine this idea -- if it's a feasible idea.. I haven't got it all thought out..

OK Paul !

Keep it as simple as possile for a good cup of coffee... The Costa Ricans -"Ticos" have been brewing their morning coffee for generations like this -- same stand as Fred Morgan demostrates in his reply... except the Ticos use a fine cloth bag and your cup goes under the bag instead of the steel cup... Just rinse the bag afer each use and it will last for many a cup... I've used it for years. "El chorreador de cafe"

Easy to make one or buy over the internet... No special cloth is needed, just a tight weave.. with a piece of stainless wire a little bigger than the hole in the stand.. Put the coffe in the bag to strength you want and pour hot water through.. A good flavored coffee ! wood part is simple...

use this system for earth built block houses.. no expensive machinery other than having a cement mixer available, one man could build the house, and not that much time to finish the walls.

For an earth block built house this is the best I've seen. Build the blocks in place in the wall.. Easier than adobe or rammed earth... Forms can be built easily out of wood instead of buying them.. No large expensive forms and relatively cheap to make..

http://www.formblock.com.au/

If you have a little expertise and time to do it yourself, cost can be held down on the system using a simple but very ingenious vortex to drive a generator, and you have a plentiful supply of electricity.. no more than 1 meter of fall is needed .... 5 meter diameter pool will produce around 14 KW

http://www.zotloeterer.com/our_company_english.php
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Another, a Banki turbine, though not producing as much power, is simple to build... and not a great head of water is needed.. cheap to build...

1 -- http://www.boutiquepower.com.au/micro-hydro/crossflow_construction_guide.pdf

2 -- http://pdf.usaid.gov/pdf_docs/PNAAP285.pdf

If anyone hasn't looked at this website for a great hydro power unit, it's worth seeing... The unit is relatively cheap and works well.

http://www.watermotor.net/index2.htm

John
The heat from the rocket exhaust heats the air to air exchanger only.. no exhaust flue gases pass in the ductwork to the house.. then, any heat passing though the thermal mass will be clean..

And yes, the heat accumulated in the storage mass (a pile of rocks in an enclosed space in the crawl space would do it) can then be drawn on, coupled with a thermostat and duct vavle to help regulate temp.... There should be immediate heat available as soon as the stove is heating, as the ductwork, although passing through the rock pile is still going straight to the house rooms so long as the duct valve is open. Don't know if a valve like this is commercially avalable, but shouldn't be difficult to build one..

As I said, the ducting is a standard system with the exception of the rock pile.. same principle as with a passive system, thermwall to rock pile, to each room, etc..
I could be wrong... but principle seems workable and details such as placement of fans shouldn't present any problem...
This idea isn't !00% off the grid.. but should cut heating bills way down....

Anyone else have an idea on this kind of arrangement??

Allen --
As far as what I mentioned, I think you misunderstand what I'm thinking about.. Don't complicate it ... Forget the idea of using the complete furnace. Just use the heat exchangers... The rocket stove replaces the heat source..

As I understand it, and I'm new to thinking of rocket stoves and have a lot to learn about them, most of the heat exchangers talked about are thermal mass sinks... An ugly barrel sitting out in the middle of the house, along with the two or three tons of cob... The use of which presents a problem of design in a new house.... As mentioned by one of the repliers in this forum...

If you have a large house ( or are designing a new one) and it already/or will have a forced air system,(or radiant heat sysyem) then all you're doing is replacing the heat source... ducting (or tubing), fans, and return air duct is already in place and sized correctly or would be if you know what you're doing...
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As to a safe distance, I was thinking of the uncontrolled heat being too hot for the exchanger.. If that isn't a problem, then the exchanger can be mounted directly to the rocket stove exhaust exit.. Blower duct fan/motors can be placed far enough from the stove to eliminate heat problems to the fan...

If there's room in the crawl space,(or design it into a new house) ducting could run into a thermal mass holding the heat and eliminating keeping a fire going all night.. fans on a thermostat can be placed in this area..

And as far as using a used furnace, I just saw a newer one for $200, in fine working condition that the owner was replaceing with a different system... So if you're got one to throw away,, just send it to me..

Hi--- New to the site..
Relating to full home heating with the rocket stove...

Having read the first few pages, I didn't come upon anything regarding using a typical forced air furnace air to air heat exchanger in conjuction with the rocket mass heater.. Has anyone addressed this?

Couldn't this type of air to air heat exchanger be connected to the exhaust end of the chimmey? The rocket stove wood heat should be no different than gas or oil fire that is directed through the exchanger provided that a sufficient distance from the chimmey is allowed to prevent extreme heating of the exchanger....Yes, the fan system is needed to propel the hot air throughout the house duct system nornally used with a forced air system....
These furnaces (used) can be bought through Craigslist very cheap, I've seen some in my area (Alaska) that are given away..

Also, for a radiant water system, why not use the same principle using the boiler exchanger, expansion tank and pumps from a conventional gas or oil fired home heating water boiler? .. Just direct the flue gases from the rocket stove to the boiler chamber at safe distance from the exchanger.....
Again there are older used boilers out there for sale cheap....Weil-McLain, etc.... and use the same radiant floor system with the PEX tubing... The PEX tubing eliminates the hard water deposits in piping....
Yes, there would have to be a heat sink, hot tub, etc..... or a steam pipe vented to an outside exit with a pressure relief valve and tempering valve at the expansion tank exit before entering the PEX manifold, eliminating pressure in the PEX piping and keeping temperature down....