Wood Heat

We are handling only one brand of wood heater. Rocky Mountain Solar is proud to be a dealer for Garn wood heaters. Garn wood-fired hydronic heaters are the high efficiency equivalent of the outdoor wood ‘boilers’ seen in many rural yards in cold climates. EXCEPT that Garns are extremely efficient and virtually smokeless (as well as being relatively simple). This is accomplished by two primary attributes: secondary combustion of wood gases (i.e., ‘gasification’) and large integrated thermal storage capacity that can absorb all of the heat from a full load of wood with no damping required.

In our opinion, no other residential or homestead-scale wood heater comes close to the quality and overall efficiency of these units. Most wood heaters use control of the air supply to regulate the amount of heat coming from the heater. This results in a smoldering, smoky fire that continues to burn at a cooler slower rate when heat is not needed. The higher efficiency of the Garn units comes from being able to burn normal firewood, fully oxygenated at a very high temperature, a batch at a time. The thermal storage is via a large water tank surrounding the firebox and exhaust.  

These are not small units: the three models available range from 1500 to 3200 US gallons of water storage and weigh in at two tons or more when empty. They are usually placed in a separate building from the house, mostly because of size. Although in the same general category as the more common self-contained outdoor wood heaters, Garn heaters require protection from the elements, usually in a dedicated building which houses the heater, circulating pump and controls. This can be combined with firewood storage or other storage, or even a shop, as long as it does not house motor vehicles or gasoline (for safety).  The hot water produced by the Garn is pumped to the house (and/or shop, greenhouse, barn, etc.) to be distributed there.

From the Garn website:
The GARN® WHS (Wood Heating System) line of wood-fired hydronic heaters combine high-efficiency wood combustion and hydronic thermal storage to make the most efficient and effective wood heating units on the market.

  • Two-Stage Combustion ensures low emissions so there is virtually no smoke, creosote, or ash.
  • Five-Pass Heat Exchanger ensures efficient combustion heat transfer into thermal storage.
  • Integrated Thermal Storage allows heat to be drawn off as needed between burns.
  • Water-Based Delivery ensures efficient transfer of the stored heat to the building or application.
  • Easy Integration with radiant floor, hot water baseboard, cast iron and European style radiators, forced air furnaces, or other heating systems allows the units to be added into existing applications or new construction.


For more information, including current prices, call or email us.