Blaze King Industries Princess PI29 Insert (2) vs Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640)
The Blaze King Industries Princess PI29 Insert (2) is the cleaner burner: 1 g/hr certified particulate emissions versus 1.1 g/hr. The Blaze King Industries Princess PI29 Insert (2) is the more efficient unit: 80% versus 79% HHV — more heat from every cord. The Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) produces more peak heat (31,581 vs 30,194 BTU/h), suiting roughly 900–1,250 sq ft. The Blaze King Industries Princess PI29 Insert (2) has the larger firebox (2.63 vs 1.32 cu ft), which generally means longer burns between reloads. Combustion technology differs: the Blaze King Industries Princess PI29 Insert (2) is a catalytic stove and the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) a hybrid — see the catalytic vs non-catalytic guide for what that means day to day.
| Blaze King Industries Princess PI29 Insert (2) | Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) | |
|---|---|---|
| Appliance type | wood-stove | wood-stove |
| Combustion technology | Catalytic Stove | Hybrid |
| Certified fuel | Crib Wood | Crib Wood |
| Emission rate | 1 g/hr | 1.1 g/hr |
| Efficiency (HHV) | 80 % | 79 % |
| Heat output (low) | 9023 BTU/h | 13876 BTU/h |
| Heat output (high) | 30194 BTU/h | 31581 BTU/h |
| Firebox volume | 2.63 cu ft | 1.32 cu ft |
| Carbon monoxide | 0.704 g/min | 0.52 g/min |
| 25C tax credit eligible (≥75% HHV) | Yes | Yes |
| 2020 NSPS compliant | Yes | Yes |
| Currently in production | Yes | Yes |
| EPA certification number | 123-18 | 210-19 |
| Covered model numbers | Princess PI29 Insert | Green Mountain 40 Series: Green Mountain 40 (8640), Craftsbury 2 (8392), Hipster 14 (AMB8240) |
Frequently asked questions
Which burns cleaner, the Blaze King Industries Princess PI29 Insert (2) or the Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640)?
The Blaze King Industries Princess PI29 Insert (2): 1 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 Blaze King Industries Princess PI29 Insert (2) and Hearthstone Quality Home Heating Products Green Mountain 40 Series: Green Mountain 40 (8640) 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.