Wood Gun™ High Efficiency Gasification Wood Boiler
The Wood Gun™ wood gasification boiler by
Alternate Heating Systems
utilizes the most advanced technology in wood burning and is perhaps
the most efficient wood burning device on the market today. This
uncompromising multifuel system is ideal for any residential
application where wood or wood by-products are used as fuel. The AHS
Wood Gun™ is available in residential sizes ranging from 100,000 to
250,000 BTU’s and commercial sizes up to 1,000,000 BTU.
Automatic cycling on and off in response to heating or hot water demand.
Domestic hot water coil provides abundant quantities of hot water.
Exceptionally safe and clean burning. The use of dense refractory
material cast into specific shapes causes complete combustion to occur
at temperatures of up to 2000° F.
When operated properly in the gasification mode, visible smoke is
eliminated and creosote formation inside the chimney is prevented.
The large cyclone separator removes most of the fly ash resulting in very
Spontaneous re-ignition of the wood will occur after an off period of 2-4 hours
Re-ignition is dependent on the refractory temperatures.
Automatic fuel delivery systems are available for wood waste products
such as sawdust, shavings, woodchips and densified biomass. These are
designed more for industrial/commercial applications rather than
Wood Gun™ readily adapts to new or existing hot air systems through the use of a heat convection coil.
The design maintains all heated walls at the same temperature using a
"water wall". This constant temperature eliminates stress fractures
caused by differences in temperature between components of the boiler
thus increasing it's life. In addition, this design produces greater
efficiency because heat that is normally lost through a drywall is
captured in the water wall.
*Average hourly BTU output is based on a 8-12 hour burn cycle
|BTU/H (Max.) Wood
|Oil (optional) **
|Fire Box Capacity
|Max. Log Length
|Domestic Coil Gal/min (Optional)
|*Rec. Sizing: for 8-12
hour burn cycle (BTU/hr)
|BTU/H (Max.) Wood
|Net Steam Rating (BTU/H)
|Gas/Oil Chamber (water capacity)
|Weight (w/o gas/oil - lbs)
|Minimum Boiler Room (w/o Gas/Oil)
|Minimum Boiler Room (with Gas/Oil)
How it Works
Wood gas is produced by applying heat to wood, a process called
pyrolysis. The wood gas is drawn through the bottom of the firebox and
into our uniquely designed refractory by an induction fan. The gases
are combined with oxygen and combusted in the refractory. The super
heated gases pass through the interconnected refractory tunnels and in
to our uniquely designed swirl chamber. This is where the bulk of heat
exchange takes place. The superheated refractory then continues to
gasify the wood remaining in the firebox. After combustion the residual
ash is combined with high velocity air flow to scrub the heat exchanger
preventing any build up. This process allows us to maintain an
unparalleled consistency in heat exchange. Most ash exits the unit and
is collected in the cyclone ash separator for fast and easy removal.
The Wood Gun™ cycles on and off much like an oil or gas fired boiler.
During the off cycle, fuel is not consumed because oxygen is not
present in the combustion chamber. With the large superheated
refractory mass, re-ignition of the fuel (usually occurs up to 5 to 6
hours later depending on boiler size) automatically when a drop in
water tempurature signals the need for heat.
During the off cycle, wood gas inside the firebox condenses on the
inner walls forming a solid that will eventually fall off. This
combines with the remaining fuel thus adding energy that in many other
boilers goes up the chimney.
Carbon vs. Stainless Steel in our Wood Boilers
The internal surfaces of a Wood Gun™ Wood Boiler include any surface
touched by the flame, smoke, wood or exhaust. The internal surfaces
may be manufactured with carbon steel or stainless steel - it's your
choice. We recommend stainless steel because carbon steel will show
deterioration within 10 years though the unit may continue to function
for as much as 20 years. We have had stainless steel boilers in
service for 20 years, and they show no sign of deterioration. We use
1/4" thick 304 stainless steel (as opposed to 409) for unsurpassed
stack temperature is an indicator of transfer efficiency. During
combustion, temperatures of around 2000° Fahrenheit can be obtained.
Amazingly, our exhaust stack temperature ranges from about 260-300°
Fahrenheit. This stack temperature is unheard of in the industry. The
Alternate Heating Systems WoodGun™ is truly the pinnacle of wood fueled