Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) vs Kuma Stove And Iron Works K-251 Series: Ashwood LE-1

The Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) is the cleaner burner: 0.53 g/hr certified particulate emissions versus 1.1 g/hr. The Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) is the more efficient unit: 80% versus 78% HHV — more heat from every cord. The Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) produces more peak heat (33,424 vs 30,612 BTU/h), suiting roughly 950–1,350 sq ft. The Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) has the larger firebox (3.16 vs 2.56 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) is a hybrid and the Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 a catalytic stove — see the catalytic vs non-catalytic guide for what that means day to day.

Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) Kuma Stove And Iron Works K-251 Series: Ashwood LE-1
Appliance type wood-stove wood-stove
Combustion technology Hybrid Catalytic Stove
Certified fuel Crib Wood Crib Wood
Emission rate 0.53 g/hr 1.1 g/hr
Efficiency (HHV) 80 % 78 %
Heat output (low) 14846 BTU/h 11219 BTU/h
Heat output (high) 33424 BTU/h 30612 BTU/h
Firebox volume 3.16 cu ft 2.56 cu ft
Carbon monoxide 0.2 g/min 0.49 g/min
25C tax credit eligible (≥75% HHV) Yes Yes
2020 NSPS compliant Yes Yes
Currently in production Yes Yes
EPA certification number 390-25 357-23
Covered model numbers Green Mountain 80-1 (Model 8681), Okemo (Model 8380), Hipster 30 (Model 8280) K-251 Series: Ashwood LE-1, Wood Classic LE-1, Cambridge LE-1, Cascade LE-1

Frequently asked questions

Which burns cleaner, the Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) or the Kuma Stove And Iron Works K-251 Series: Ashwood LE-1?

The Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681): 0.53 g/hr certified particulate emissions versus 1.1 g/hr for the Kuma Stove And Iron Works K-251 Series: Ashwood LE-1.

Are the Hearthstone Quality Home Heating Products Green Mountain 80-1 (Model 8681) and Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 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.