Advanced Wood Heat
Salmon Arm, BC.
A Masterpiece of Simplicity
GARN has proven itself to be the most durable wood boiler
in the industry with an unmatched history of longevity, reliability and
efficient performance. With only 2 moving parts, the door and the fan, the GARN
is a masterpiece of simplicity and reliability.
The GARN Wood Heating
System can be sizeded to heat residential, commercial, or agricultural
applications. When installed in tandem, multiple GARN units can be used to heat
multiple building, large commercial and public facilities such as arenas,
schools or hospitals.
See How a GARN Works.
Announcing the latest addition to the GARN family
gallon GARN JR.
New Emissions Report
In March/April 2011, a production GARN WHS 1500 unit was tested
by Intertek Testing, an independent test laboratory.
results of this independent test are:
***.13 lbs of particulate/million BTUs
***3.91 grams/hour year round particulate rating
The emission results are 57% less than the current EPA Phase II
Limit of .32 lbs of particulate per million BTUs delivered. This emission
result is also 73% less than the commercial limit of .60 lbs of particulate per
million BTUs delivered.
Click to see
the full emissions report:
The GARN line of Wood Heating Systems (WHS), have been an
integral part of developing wood as a viable, clean, and effective renewable,
carbon neutral heating source. The GARN WHS 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. *Smokeless because approximately
15 minutes after starting a fire, your GARN unit burns so efficiently, that
little smoke is produced!
||Five-Pass Heat Exchanger ensures efficient
combustion heat transfer into thermal storage.
Integrated Thermal Storage allows heat to be drawn off as needed between
||Water-Based Delivery ensures efficient transfer of
the stored heat to the building or application.
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
GARN units are certified by independent lab tests to
comply with all applicable UL and CSA Standards, and are the only wood-fired
hydronic heater certified for both horizontal and vertical flue venting. Our
boilers are certified to burn cord or slab wood; pallet and other scrap wood;
dense wood briquettes; and air dried corn on the cob.
GARN® WHS Technical Specifications
Emissions rate PM2.5
|Width in Inches
|Overall Length in
|Weight Empty in
|Weight Filled in
|Firebox Length in
|Btu/hr Max. Heat
Maximum heat output
is based on reloading once every 3 hours with 24 inch long split white oak,
with 20% moisture content. Output rate is fuel dependent and will vary with
wood type, moisture content, size and reloading frequency. GARN® WHS units
are certified safe to burn cord or slab wood, densified wood briquettes and air
dried corn on the cob.
*Tested to ASTM-E2618
|GARN units comply with all applicable UL and CSA safety standards,
and because of their low exhaust temperatures, are the only wood-fired hydronic
heaters certified for both horizontal or vertical flue venting in the United
States. Our units are certified to burn cord wood, slab wood, pallet and other
scrap wood, dense wood briquettes, and air-dried corn on the cob.
How it Works.
Combustion air is drawn directly from outdoors through an internal
air inlet tube (A) to the air distribution collar (B). The
outdoor air is preheated as it travels through the air inlet tube (A)
and the air distribution collar (B). This yields more efficient
A compliant seal on the loading door (C) prevents room air
from entering the combustion chamber (E). The loading door is insulated
to prevent heat loss and includes an air-cooled heat shield to minimize hot
surfaces near the user.
Combustion air from the collar (B) flows through upper and
lower nozzles (D) into the combustion chamber (E).
Additional air from the upper nozzle is mixed with hot gases from
primary combustion before entering the ceramic secondary combustion chamber
Within the ceramic chamber, smoke, creosote and particulates are
burned in a very turbulent, horizontal gasification process at temperatures
near and above 2000 ºF.
After exiting the secondary combustion chamber, the hot gases are
drawn through a 5-pass tubular heat exchanger (G) transferring their
heat to the water in the tank.
The cooled gases are then drawn into the Draft Inducer Fan (H)
and pushed out of the exhaust pipe (I) at temperatures less than 350
||garn whs 1500
Certified to be Installed Indoors
| Non-Pressurized Thermal Storage
Overnight Loading or Fire Required
Low Maintenance Construction
Combustion (Gasification) Chamber
|5 Pass Heat
Load Fuel Chamber
Insulated Loading Door
||Cool to the
Touch Loading Door
||No Smoke in
Your Face when Reloading Fuel
Return (HWR) Dispersion Tube
Water Treatment Minimize Corrosion
Air Supplied from Outside
|30 Years of