The Fabrication Process
Each Zaug is custom made to order. There are over 50 individual pieces of steel welded together to complete one stove. The 12 gauge cylinder and 2″ trim must be rolled before it can be welded. Once all the welding is complete, the surfaces are sanded, washed in lacquer thinner, and primed for paint. A coat of Thurmalox 2-part zinc primer is applied and allowed to dry for 24 hours. Then, two coats of Thurmalox paint is sprayed to a 2 mil thickness for a smooth finish. The final touch is a coat of Thurmalox high temperature clear coat for a gloss finish. Fabrication takes approximately 28 days from start to finish.
Below is a video showing one small part of the fabrication process; How the cylinder is made:
In our tests, the Zaug Standard burns about 1 cubic foot of wood in 4 hours. If you consider that a pound of wood has 8000 BTU’s (acceptable rate per Sam Foote P.ENG.), and there’s 21 pounds of wood in a cubic foot (Pine or Fir), therefore the amount of heat given off after burning a cubic foot of wood is 168,000 BTU’s in 4 hours. That doesn’t mean the stove gives off that amount heat, it only means that, 168,000 BTU’s was produced by the fire. Some heat will travel out the exhaust to the outside air, and some will travel in to the home through the stove. Now, if you can capture at least 90% (most rocket mass heater/thermal mass units capture 95-96%) of that heat created, and retain that heat within your house through the thermal mass and exhaust line retention, you will have approximately 151,200 BTU’s of heat over 4 hours. That’s 37,800 BTU’s/hour produced from sticks and branches.
There’s 128 cu. ft. in a cord of wood, burning 1 cu. ft. a day, would yield approximately 128 four-hour fires. Or, 128 days of warmth. A four-hour fire is enough to heat up your mass and nearly heat you out of your home.
The standard Zaug Stove operates best with sticks and branches, but the Altaire can handle 6” rounds up to 24” long. The fire eats a hopper of sticks and branches in about 30-45 minutes in the Standard, and 1 – 1.25 hours in the Altaire (depending on how long your mass is, what type of wood burned, damper door setting, etc.). A solid round of hardwood will burn in about two hours.
We have tested our exhaust up to 47 feet before we change the direction to vertical. However, at 47 feet, we experienced some backdrafting and very slow exhaust movement. We recommend the exhaust be shortened to 25′ to eliminate back drafting and maintain optimal flow from the unit. Adding a vertical section at the end of the run, dramatically increases the draw through the system.
The Thermal Mass
The most beneficial way to use a Zaug stove, is to add a thermal mass around the stove exhaust, to capture and store heat from the exhaust. The easiest way to do this is to make a bench or hearth out of cob or clay. Brick or masonry can be used for a bench or mantle as well.
Shown left, we have built a cob bench in a barley growing room. The exhaust duct is in the center of the cob. In your home, the bench would likely run along a wall and can be used to sit or lay on.
For more information on how to build a thermal mass, research Rocket Mass Heaters on the internet.
Glass (Altaire Model Only)
By far, the most appealing feature about the newly designed Altaire has got to be the glass lid for viewing the fire. The Return Air Port System allows air to flow in to the unit from the grated side grills, thereby, allowing the feed tube lid to be closed while in full operation. This glass is a 6″ x 9″ window made of 9/16″ thick Neoceram heat resistant glass. It’s capable of withstanding temps of 1200 °F (648.88 °C).
For heating greenhouses, the exhaust duct can be installed in grow beds, or in specific situations the soil, so that it runs approximately 6 inches underground to heat the soil. The soil or grow bed will act as a thermal mass and retain heat for several hours. If you have an aquaponics system, you may even consider wrapping a coil around the Zaug exhaust to heat the water in your system. The exhaust duct temperature is approximately 225 degrees. Extreme care would have to be taken to avoid over-heating the fish.
The cooktop of the stove can be easily removed for access to the interior, for quick cleaning. There is an easy-access ash pit, resting in the pedestal, for removing burned ash. The air-intake chamber over the feed tube, on the Standard Zaug, is dampened down and can be completely closed off with the bi-fold hinged door on the top of the intake.
It is not recommended to install a Standard Zaug in a basement situation where the basement is not the main relaxing area. The reason is that the Standard Zaug needs more attention than a conventional wood stove, and therefore should be placed in an area where it can be watched and filled readily. A better choice would be to use the Altaire with a one-hour burn time.
- We offer custom placement of the exhaust port anywhere on a 90 degree swivel, left or right. When designing your system, tell us where you want the exhaust line to go and we can accommodate your needs. For instance, if your stove sits in a corner, and your thermal mass runs along a wall at a 90 degree angle, we can place the exhaust port to exit the stove right where your mass starts.
- For dual exhaust runs, we can weld dual ports on either side of the cylinder. This might be helpful for greenhouse applications or a secondary port for a priming run.
- We offer a cold air return port placed in the base of the pedestal. This port will allow air to come in from outside or wherever you choose.
- We offer many styles of ash pit drawer handles.
- We offer many colors to choose from.
- For extra paint protection, we can spray a clear lacquer coat to give a gloss look and an easy surface to wipe down.
Stove weight is 340lbs (154.22kg) for the standard Zaug and 420lbs (174.63kg) for the Zaug Altaire. Shipping weight is 440lbs (199.581kg) for the Standard and 520lbs (235.868kg) for the Altaire. The shipping crate weighs 120 lbs. We ship from Yelm, WA 98597. We use a shipping broker for our shipping needs in continental US and Canada, and Old Dominion for our ocean freight voyages.
Fabrication takes approximately 28 days from start to finish. Please be patient if we go over by a couple days. We tend to get orders in waves, and it becomes a challenge to keep on schedule.
Comparison of the Standard Zaug to the Zaug Altaire:
|Price||$2,100.00||$2,100.00 (Special Introductory Price)|
|Height||42” (106.68cm) High||42” (106.68cm) High|
|Diameter||21” (53.34cm)||21” (53.34cm)|
|Stove Weight||340lbs (154.22kg)||420lbs (174.63kg)|
|Cooktop Weight||30lbs (13.61kg)||32lbs (14.52kg)|
|Cylinder||12ga. light carbon steel||12ga. light carbon steel|
|Combustion Chamber||7 5/8” square x 3/8” (19.36cm square x .9525cm) Steel tube||7 5/8” square x 3/8” (19.36cm square x .9525cm) Steel tube|
|Insulation Chamber||Welded 16ga. sheet steel filled with 2” Perlite volcanic rock||Welded 16ga. sheet steel filled with 2” Perlite volcanic rock|
|Ash Pit Drawer||5” x 5” x 8” (12.7kg x 12.7kg x 20.32kg)Black Steel Handle||5” x 5” x 8” (12.7kg x 12.7kg x 20.32kg)Stainless Steel Handle|
|Feed Tube Opening||6.25” x 7.5” (15.875cm x 19.05cm)||7.25” x 9.5” (18.415cm x 24.13cm)|
|Return-Air Port System||Optional||Complete RAPS|
|Cold Air Return Inlet||Optional||Optional|
|Feed Tube Glass Door||Optional||Yes|
|Primer||Thurmalox 245 Zinc Primer||Thurmalox 245 Zinc Primer|
|Finish||Thurmalox 270 High Temperature PaintOptional High Temperature Clear Lacquer||Thurmalox 270 High Temperature PaintOptional High Temperature Clear Lacquer|
|Colors||8 Standard Colors(Optional 16 more with $50 charge)||8 Standard Colors(Optional 16 more with $50 charge)|
|Operating Temps||Cooktop Plate 450-800°F (232-426°C)Cylinder 250-500°F (120-260°C)Exhaust 90-200°F (32-93°C)||Cooktop Plate 450-800°F (232-426°C)Cylinder 300-500°F (149-260°C)Exhaust 125-290°F (51-137°C)|
|Exhaust Port Size||Standard US 6” HVAC Duct(Optional sizes for Europe)||Standard US 6” HVAC Duct(Optional sizes for Europe)|
|Fuel Source||Dry wood, sticks, branches only.No Pellets||Dry wood, small rounds, wedges.No Pellets|
|Burn Time||30 – 45 minutes per hopper||1 – 1.25 hours per hopper|
|Warranty||3 Years / Parts and Workmanship||3 Years / Parts and Workmanship|
|Shipping Weight||440lbs (199.581kg)||520lbs (235.868kg)|
We are in the process of certifying the Zaug Stove with the proper EPA and UL regulations; However, at this time, the Zaug Stove is not recognized as a conventional wood burning stove by the EPA. Unfortunately, the EPA does not have a test for this new type of wood burning technology. It may be some time before an independent research and development team can design a test for our stove. Thank you.