The gasification process does continue during the Wood Gun™ shutdown phase. However, when the gas is not ignited, it changes to a solid state when it contacts the walls of the fuel box and is held there. When re-ignition occurs, the gas solids fall off of the wall and are burned thus self-cleaning the walls of the fuel box and ensuring that nearly all the energy in the wood is retained during the shutdown phase.

The maximum rating is the maximum possible BTU output. The recommended rating is the BTU/hr rating that must be used to achieve an 8 to 10 hour burn cycle.

The Wood Gun™ Wood Gasification Boiler can burn wood with a wider range of moisture content than can a non-gasification wood boiler. Wood with a 20% to 30% moisture content is optimal. See also moisture content of wood for an explanation of the heating value of wood at various moisture contents.

Yes. See operating an Alternate Heating Systems Boiler in tandem with another boiler. The supplies needed for hooking up a second boiler (such as tubing, circulators and flow valves) are not available from Alternate Heating Systems but must be purchased locally.

Yes - a tempering valve must be used. Boilers must be operated with water temperatures at 170-190 degrees Fahrenheit while water running through radiant tubing should typically not be more than 120 degrees Fahrenheit. A tempering valve is an inexpensive option that works to lower the temperature of the water going into the radiant lines by mixing the cooled water that is returning to the boiler with the heated water that is flowing from the boiler. The tempering valve has a dial that can be turned to set the desired temperature of the water being fed into the radiant lines.

The Goal Gun automatic stoker boiler requires very little maintenance outside of routine ash removal. We recommend that you inspect your machine every three months for wear and tear. You should lubricate the roller chains with chain oil and take up any slack, lubricate the Pitman shaft brass bushings with a few drops of oil, grease the fan shaft bearings with high temperature grease, and check and replace or adjust the tension on the drive belt at this time as well. Every six months, check the abrasion shield for leakage around the gasket and replace if necessary. Also, this is a good time to check for leakage around the flue pipe seams and re-seal if necessary. Once every heating season, we recommend that you inspect the boiler thoroughly to ensure it is in working order. Check the cam bearings on the grate and make sure they are free to rotate. The cyclone should be inspected for particulate build-up along with the funnel and cleaned if necessary. Also, clean and inspect the fire box and swirl chamber in the boiler. Finally, inspect the ceramic heat shield between the draft fan and the boiler. Specifically, if the fan shaft has worn the heat shield back to a gap of greater than about 1/6”, replace the heat shield. Any replacement parts can be obtained directly from Alternate Heating Systems. For a more detailed description of routine maintenance tasks and troubleshooting procedures, please consult your operator manual.

Note: If you burn a lower quality anthracite coal, you may need to frequently check the fire bed for clinkers and remove them as necessary.

Note: The chimney connector and chimney should be inspected at least twice monthly during the heating season to determine if ash buildup has occurred. If ash accumulates, it restricts draft and reduces efficiency.

Note: Before maintenance or cleaning, make sure that the fire is out or the unit has cycled off for at least four hours and the power is disconnected.

Only Anthracite coal. See also Anthracite Coal Suppliers.

You can load coal into the hopper with either a shovel or bucket. You could also purchase an auger at a local agricultural supply store to transport coal to the boiler from a bin.

No, only pea or buckwheat anthracite coal can be burned in a Coal Gun. Rice coal causes the airflow to be too restricted. See also Anthracite Coal Dealers.

A ton of anthracite occupies 40-43 cubic fee or an area approximately 3.5 feet by 3.5 feet by 3.5 feet. See also Space Occupied by Coal.