Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) vs Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal

The Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal is the cleaner burner: 1 g/hr certified particulate emissions versus 1.1 g/hr. They tie on efficiency at 79% HHV. The Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) produces more peak heat (31,581 vs 27,294 BTU/h), suiting roughly 900–1,250 sq ft. The Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) has the larger firebox (1.32 vs 1.15 cu ft), which generally means longer burns between reloads.

Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal
Appliance type wood-stove wood-stove
Combustion technology Hybrid Hybrid
Certified fuel Crib Wood Crib Wood
Emission rate 1.1 g/hr 1 g/hr
Efficiency (HHV) 79 % 79 %
Heat output (low) 13876 BTU/h 15332 BTU/h
Heat output (high) 31581 BTU/h 27294 BTU/h
Firebox volume 1.32 cu ft 1.15 cu ft
Carbon monoxide 0.52 g/min 0.15 g/min
25C tax credit eligible (≥75% HHV) Yes Yes
2020 NSPS compliant Yes Yes
Currently in production Yes Yes
EPA certification number 210-19 108-17
Covered model numbers Green Mountain 40 Series: Green Mountain 40 (8640), Craftsbury 2 (8392), Hipster 14 (AMB8240) 212N Navajo Hybrid Wood-Coal, 212S Survival Hybrid Wood-Coal

Frequently asked questions

Which burns cleaner, the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) or the Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal?

The Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal: 1 g/hr certified particulate emissions versus 1.1 g/hr for the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640).

Are the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) and Woodstock Soapstone Company 212N Navajo Hybrid Wood-Coal both EPA certified?

Yes — both appear on the U.S. EPA's current list of certified wood heaters, and every figure on this page comes from their certification records.