Hearth and Home Technologies Quadra-Fire 21M-ACC-C vs Stove Builder International SR-3.2 Series: St-Louis
The Hearth and Home Technologies Quadra-Fire 21M-ACC-C is the cleaner burner: 1.7 g/hr certified particulate emissions versus 1.8 g/hr. They tie on efficiency at 76% HHV. The Stove Builder International SR-3.2 Series: St-Louis produces more peak heat (83,857 vs 29,322 BTU/h), suiting roughly 2,400–3,350 sq ft. The Stove Builder International SR-3.2 Series: St-Louis has the larger firebox (3.15 vs 1.48 cu ft), which generally means longer burns between reloads.
| Hearth and Home Technologies Quadra-Fire 21M-ACC-C | Stove Builder International SR-3.2 Series: St-Louis | |
|---|---|---|
| Appliance type | wood-stove | wood-stove |
| Combustion technology | Non-Catalytic Stove | Non-Catalytic Stove |
| Certified fuel | Crib Wood | Crib Wood |
| Emission rate | 1.7 g/hr | 1.8 g/hr |
| Efficiency (HHV) | 76 % | 76 % |
| Heat output (low) | 13585 BTU/h | 29605 BTU/h |
| Heat output (high) | 29322 BTU/h | 83857 BTU/h |
| Firebox volume | 1.48 cu ft | 3.15 cu ft |
| Carbon monoxide | 1.5 g/min | 1.4 g/min |
| 25C tax credit eligible (≥75% HHV) | Yes | Yes |
| 2020 NSPS compliant | Yes | Yes |
| Currently in production | Yes | Yes |
| EPA certification number | 250-20 | 398-25 |
| Test method | — | Alternate Test Method Used |
| Covered model numbers | Quadra-Fire 21M-ACC-C, Discovery-1-C, FF-WP-100 | SR-3.2 Series: St-Louis, Helia, Elevate, Chambly, HEA200 |
Frequently asked questions
Which burns cleaner, the Hearth and Home Technologies Quadra-Fire 21M-ACC-C or the Stove Builder International SR-3.2 Series: St-Louis?
The Hearth and Home Technologies Quadra-Fire 21M-ACC-C: 1.7 g/hr certified particulate emissions versus 1.8 g/hr for the Stove Builder International SR-3.2 Series: St-Louis.
Are the Hearth and Home Technologies Quadra-Fire 21M-ACC-C and Stove Builder International SR-3.2 Series: St-Louis 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.