Kuma Stove And Iron Works K-181 Series: Aspen LE-1 vs Stove Builder International 1.4 Series (Osburn 950
The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 is the cleaner burner: 1.1 g/hr certified particulate emissions versus 1.8 g/hr. The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 is the more efficient unit: 78% versus 74% HHV — more heat from every cord. The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 produces more peak heat (29,153 vs 26,500 BTU/h), suiting roughly 850–1,150 sq ft. The Kuma Stove And Iron Works K-181 Series: Aspen LE-1 has the larger firebox (1.821 vs 1.55 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Kuma Stove And Iron Works K-181 Series: Aspen LE-1 is a catalytic stove and the Stove Builder International 1.4 Series (Osburn 950 a non-catalytic stove — see the catalytic vs non-catalytic guide for what that means day to day.
| Kuma Stove And Iron Works K-181 Series: Aspen LE-1 | Stove Builder International 1.4 Series (Osburn 950 | |
|---|---|---|
| Appliance type | wood-stove | wood-stove |
| Combustion technology | Catalytic Stove | Non-Catalytic Stove |
| Certified fuel | Crib Wood | Cord Wood |
| Emission rate | 1.1 g/hr | 1.8 g/hr |
| Efficiency (HHV) | 78 % | 74 % |
| Heat output (low) | 12764 BTU/h | 12100 BTU/h |
| Heat output (high) | 29153 BTU/h | 26500 BTU/h |
| Firebox volume | 1.821 cu ft | 1.55 cu ft |
| Carbon monoxide | 0.45 g/min | 1.2 g/min |
| 25C tax credit eligible (≥75% HHV) | Yes | No |
| 2020 NSPS compliant | Yes | Yes |
| Currently in production | Yes | Yes |
| EPA certification number | 346-23 | 289-21 |
| Covered model numbers | K-181 Series: Aspen LE-1, Tamarack LE-1, Aberdeen LE-1, and Alpine LE-1 | 1.4 Series (Osburn 950, Escape 1200, Gateway 1400, Solution 1.4, Spark II, Fox, Déco Nano, S250, Harmony 1.4, HES140, Blue Ridge 100) |
Frequently asked questions
Which burns cleaner, the Kuma Stove And Iron Works K-181 Series: Aspen LE-1 or the Stove Builder International 1.4 Series (Osburn 950?
The Kuma Stove And Iron Works K-181 Series: Aspen LE-1: 1.1 g/hr certified particulate emissions versus 1.8 g/hr for the Stove Builder International 1.4 Series (Osburn 950.
Are the Kuma Stove And Iron Works K-181 Series: Aspen LE-1 and Stove Builder International 1.4 Series (Osburn 950 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.