Stove Builder International SR-3.6 Series Heat Commander
Stove Builder International SR-3.6 Series Heat Commander is a non-catalytic forced-air furnace from Stove Builder International with 77% HHV efficiency and a 13,297–42,234 BTU/h output range (previously certified, no longer in production).
Previously certified (out of production). This model appears in the
EPA Certified Wood Heater Database but is no longer on the current certified list,
which usually means it is no longer manufactured. The specifications below are its
certified figures, kept for reference and for owners of installed units. Browse
currently certified heaters for models
sold new today.
General
Appliance type
forced-air-furnace
Combustion technology
Non-Catalytic Stove
Certified fuel
Cord Wood
Covered model numbers
SR-3.6 Series Heat Commander, Caddy Advanced, Caddy Advanced CR
Efficiency
Efficiency (HHV)
77 %
Heat output
Heat output (low)
13297 BTU/h
Heat output (high)
42234 BTU/h
Firebox volume
3.6 cu ft
Emissions
Carbon monoxide
1.54 g/min
Certification
25C tax credit eligible (≥75% HHV)
Yes
2020 NSPS compliant
Yes
Currently in production
No
EPA certification number
20FAF-20a
What space does the Stove Builder International SR-3.6 Series Heat Commander suit?
The 3.6 cu ft firebox puts it in the large-home, overnight-burn
class.
Certified burning Cord Wood — the test fuel closest to real-world firewood.
Is the Stove Builder International SR-3.6 Series Heat Commander EPA certified?
The Stove Builder International SR-3.6 Series Heat Commander holds EPA certification number 20FAF-20a but is no longer on the current certified list — it is previously certified, which usually means the model is out of production. Already-installed units are unaffected by that status in most jurisdictions.
Does the Stove Builder International SR-3.6 Series Heat Commander qualify for a federal tax credit?
No — the federal 25C credit for biomass stoves was terminated for property placed in service after December 31, 2025. The Stove Builder International SR-3.6 Series Heat Commander's certified efficiency is 77% HHV, which met the credit's ≥75% HHV threshold while it existed. State and local incentive programs may still apply — check your state energy office and air district.
