Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) vs Travis Industries Rockport NexGen-Hybrid

The Travis Industries Rockport NexGen-Hybrid is the cleaner burner: 0.73 g/hr certified particulate emissions versus 1.1 g/hr. The Travis Industries Rockport NexGen-Hybrid is the more efficient unit: 80% versus 79% HHV — more heat from every cord. The Travis Industries Rockport NexGen-Hybrid produces more peak heat (42,722 vs 31,581 BTU/h), suiting roughly 1,200–1,700 sq ft. The Travis Industries Rockport NexGen-Hybrid has the larger firebox (2.04 vs 1.32 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) is a hybrid and the Travis Industries Rockport NexGen-Hybrid a catalytic stove — see the catalytic vs non-catalytic guide for what that means day to day.

Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) Travis Industries Rockport NexGen-Hybrid
Appliance type wood-stove wood-stove
Combustion technology Hybrid Catalytic Stove
Certified fuel Crib Wood Crib Wood
Emission rate 1.1 g/hr 0.73 g/hr
Efficiency (HHV) 79 % 80 %
Heat output (low) 13876 BTU/h 12594 BTU/h
Heat output (high) 31581 BTU/h 42722 BTU/h
Firebox volume 1.32 cu ft 2.04 cu ft
Carbon monoxide 0.52 g/min 0.493 g/min
25C tax credit eligible (≥75% HHV) Yes Yes
2020 NSPS compliant Yes Yes
Currently in production Yes Yes
EPA certification number 210-19 362-24
Covered model numbers Green Mountain 40 Series: Green Mountain 40 (8640), Craftsbury 2 (8392), Hipster 14 (AMB8240) Rockport NexGen-Hybrid

Frequently asked questions

Which burns cleaner, the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) or the Travis Industries Rockport NexGen-Hybrid?

The Travis Industries Rockport NexGen-Hybrid: 0.73 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 Travis Industries Rockport NexGen-Hybrid 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.