Jotul North America (Jotul U.S.A., Inc.) F35 vs Kuma Stove And Iron Works K-181 Series: Aspen LE-1
The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 is the cleaner burner: 1.1 g/hr certified particulate emissions versus 1.2 g/hr. The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 is the more efficient unit: 78% versus 69% HHV — more heat from every cord. The Jotul North America (Jotul U.S.A., Inc.) F35 produces more peak heat (59,443 vs 29,153 BTU/h), suiting roughly 1,700–2,400 sq ft. The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 has the larger firebox (1.821 vs 1.57 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Jotul North America (Jotul U.S.A., Inc.) F35 is a non-catalytic stove and the Kuma Stove And Iron Works K-181 Series: Aspen LE-1 a catalytic stove — see the catalytic vs non-catalytic guide for what that means day to day.
| Jotul North America (Jotul U.S.A., Inc.) F35 | Kuma Stove And Iron Works K-181 Series: Aspen LE-1 | |
|---|---|---|
| Appliance type | wood-stove | wood-stove |
| Combustion technology | Non-Catalytic Stove | Catalytic Stove |
| Certified fuel | Cord Wood | Crib Wood |
| Emission rate | 1.2 g/hr | 1.1 g/hr |
| Efficiency (HHV) | 69 % | 78 % |
| Heat output (low) | 13533 BTU/h | 12764 BTU/h |
| Heat output (high) | 59443 BTU/h | 29153 BTU/h |
| Firebox volume | 1.57 cu ft | 1.821 cu ft |
| Carbon monoxide | 1.35 g/min | 0.45 g/min |
| 25C tax credit eligible (≥75% HHV) | No | Yes |
| 2020 NSPS compliant | Yes | Yes |
| Currently in production | Yes | Yes |
| EPA certification number | 317-22 | 346-23 |
| Covered model numbers | F35 | K-181 Series: Aspen LE-1, Tamarack LE-1, Aberdeen LE-1, and Alpine LE-1 |
Frequently asked questions
Which burns cleaner, the Jotul North America (Jotul U.S.A., Inc.) F35 or the Kuma Stove And Iron Works K-181 Series: Aspen LE-1?
The Kuma Stove And Iron Works K-181 Series: Aspen LE-1: 1.1 g/hr certified particulate emissions versus 1.2 g/hr for the Jotul North America (Jotul U.S.A., Inc.) F35.
Are the Jotul North America (Jotul U.S.A., Inc.) F35 and Kuma Stove And Iron Works K-181 Series: Aspen 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.