Wood Boilers

About the Wood Gun

The Wood Gun line is some of the most fuel-efficient wood boilers on the market.  This uncompromising multifuel system is ideal for any residential application where conventional log wood is used as fuel.

A traditional wood boiler wastes two-thirds of your wood’s energy potential. The Wood Gun is a wood gasification boiler.  This enables it to capture 66% more of the energy in each piece of wood, transforming it all into clean, consistent heat. We use high-quality stainless steel in our boilers which is what gives them incredible durability and longevity, unsurpassed by our competitors. The Wood Gun has been made in Pennsylvania since 1981.

The Wood Gun was built to reduce the labor involved in standard maintenance.

The Wood Gun spares you considerable wood-splitting time because they are able to handle logs up to 10 inches in diameter. You can burn logs of up to 29% moisture, which cuts down on wood curing time. Unlike European-style wood gasifiers, our wood boiler excels on full rounds of firewood. Our signature Exhaust Scrubbing technology makes the Wood Gun’s heat exchanger self-cleaning. So, the only cleaning you’ll have to do is weekly ash disposal and year-end cleaning.

The Wood Gun line can be used with any heating application (water-based, steam, forced-air).

How it Works

The Self-feeding Option

You can upgrade our commercial wood boilers to be self-feeding! Our self-feeding boilers use a top loading setup. An auger moves the fuel from the storage bin and brings it to the top of the boiler. The fuel is then dropped into a rotary air-lock. This rotary air-lock acts as a fire block. The self-feeding system is controlled by photo eyes. The photo eyes watch the fuel level in the firebox and when the pile drops too low, the eyes will then signal the self-feeding system to turn on.

Gasification

When the wood is heated to 25-350F, it releases its gas. This process is called pyrolysis. The induction fan draws the wood gas through the bottom of the firebox and into our uniquely designed combustion chamber, which is underneath the firebox.  The combustion chamber is made up of cast refractory sections that are arranged in such a way as to create several tunnels.  Refractory is very similar to typical firebrick, however, the refractory bricks have slots that allow the burning fuel and gasses to enter the combustion chamber. In auto-feed setups, special fuel diversion bricks prevent small fuel particles from falling through the slots.  We combine the wood gases with oxygen, which creates super-heated and clean combustion in the refractory. The super-heated gases pass through the interconnected refractory tunnels and into our uniquely designed swirl chamber. This is where the bulk of heat exchange takes place. Above the heat exchanger, the superheated refractory continues to gasify the wood that still remains in the firebox. After combustion, we use the residual ash and a high-velocity airflow to scrub the heat exchanger preventing any build-up. This process leads to unparalleled consistency in heat exchange.

Swirl Chamber

A draft fan draws the gases down into the combustion chamber. The fuel can burn upside down, effectively, due to the negative pressure created by the draft fan. Burning in this manner allows fuel to be loaded continuously with no worry of extinguishing the fire. Once the fire exits the combustion chamber, it enters our signature Swirl Chamber. This is where most of the heat exchange takes place. The gases are put into a swirling action as they pass through the Swirl Chamber. This swirling action will actually clean the walls of the heat exchanger, greatly extending cleaning intervals. After the Swirl Chamber, the cooled air then exits at a temperature of about 350 F into the flue.

Off-Cycle

The Wood Gun cycles on and off much like an oil or gas-fired boiler. All of the doors and the automatic air intake (air-valve) are gasketed. Therefore, during the off-cycle, air does not enter the boiler. This causes the fire to go out quickly and combustion to stop. Without fire, the boiler cannot make more heat, so overheating is never an issue. 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, adding energy that, in many other boilers, goes up the chimney.  When air is allowed back into the wood chamber, the huge, superheated refractory immediately rekindles the fire and the Wood Gun starts generating heat again (if re-ignition occurs within approximately 4 hours of the last time wood was burning).

Smoke

The Wood Gun wood gasification boiler, when installed, maintained, and operated properly, produces no visible smoke and prevents creosote formation in the chimney.

Stack Temperature

Exhaust stack temperature is one indicator of transfer efficiency. During combustion, temperatures reach around 2000° Fahrenheit. Amazingly, our exhaust stack temperature ranges from about 260-300° Fahrenheit. This stack temperature is unheard of in the industry. The Alternate Heating Systems Wood Gun™ is truly the pinnacle of wood-fueled heating devices!

Best Warranty in the Industry

Wood Gun boilers use ¼” thick Type 304 stainless steel in the construction of the firebox, heat exchanger, and door frames. We use Type 304 stainless steel for its unsurpassed quality and longevity. Our stainless-steel boilers show no signs of deterioration, even after well over 35 years of service. This is why we gave our Wood Gun vessels a 20-year warranty, with the first 10 years being completely covered for both labor and materials! We stand behind our products and trust our team who builds them!

Standard Equipment

Standard equipment includes an insulated boiler jacket, totally enclosed motor and drive systems, primary and backup aquastat thermostats, pressure relief valve, and ash pan.

Maintenance

Weekly cleaning allows for optimal performance. The easy-access front, bottom inspection door, along with the included ash rake, makes cleaning fast and convenient.

¹An assortment of fuels can be used, such as corn, nutshells, cherry seeds, and paper pellets. Fuel sources are restricted only by natural concerns, like the amount of soot produced, fuel economy concerns, availability, and BTUs per pound.