Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 vs Woodstock Soapstone Company Progress Hybrid 209b

The Woodstock Soapstone Company Progress Hybrid 209b is the cleaner burner: 0.46 g/hr certified particulate emissions versus 1.1 g/hr. The Woodstock Soapstone Company Progress Hybrid 209b is the more efficient unit: 80% versus 78% HHV — more heat from every cord. The Woodstock Soapstone Company Progress Hybrid 209b produces more peak heat (35,222 vs 30,612 BTU/h), suiting roughly 1,000–1,400 sq ft. The Woodstock Soapstone Company Progress Hybrid 209b has the larger firebox (2.8 vs 2.56 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 is a catalytic stove and the Woodstock Soapstone Company Progress Hybrid 209b a hybrid — see the catalytic vs non-catalytic guide for what that means day to day.

Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 Woodstock Soapstone Company Progress Hybrid 209b
Appliance type wood-stove wood-stove
Combustion technology Catalytic Stove Hybrid
Certified fuel Crib Wood Crib Wood
Emission rate 1.1 g/hr 0.46 g/hr
Efficiency (HHV) 78 % 80 %
Heat output (low) 11219 BTU/h 15257 BTU/h
Heat output (high) 30612 BTU/h 35222 BTU/h
Firebox volume 2.56 cu ft 2.8 cu ft
Carbon monoxide 0.49 g/min 0.07 g/min
25C tax credit eligible (≥75% HHV) Yes Yes
2020 NSPS compliant Yes Yes
Currently in production Yes Yes
EPA certification number 357-23 406-25
Covered model numbers K-251 Series: Ashwood LE-1, Wood Classic LE-1, Cambridge LE-1, Cascade LE-1 Progress Hybrid 209b

Frequently asked questions

Which burns cleaner, the Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 or the Woodstock Soapstone Company Progress Hybrid 209b?

The Woodstock Soapstone Company Progress Hybrid 209b: 0.46 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 Kuma Stove And Iron Works K-251 Series: Ashwood LE-1 and Woodstock Soapstone Company Progress Hybrid 209b 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.