Wolf Steel Napoleon S25
Wolf Steel Napoleon S25 is a non-catalytic wood stove from Wolf Steel certified at 1.3 g/hr particulate emissions with 72% HHV efficiency and a 19,195–54,057 BTU/h output range (previously certified, no longer in production).
Previously certified (out of production). This model appears in the EPA Certified Wood Heater Database but is no longer on the current certified list, which usually means it is no longer manufactured. The specifications below are its certified figures, kept for reference and for owners of installed units. Browse currently certified heaters for models sold new today.
| Appliance type | wood-stove |
|---|---|
| Combustion technology | Non-Catalytic Stove |
| Certified fuel | Cord Wood |
| Covered model numbers | Napoleon S25, Napoleon S25i, Timberwolf T25, Timberwolf T25i |
| Emission rate | 1.3 g/hr |
|---|---|
| Carbon monoxide | 1.77 g/min |
| Efficiency (HHV) | 72 % |
|---|
| Heat output (low) | 19195 BTU/h |
|---|---|
| Heat output (high) | 54057 BTU/h |
| Firebox volume | 2.51 cu ft |
| 25C tax credit eligible (≥75% HHV) | No |
|---|---|
| 2020 NSPS compliant | Yes |
| Currently in production | No |
| EPA certification number | 266-20 |
What space does the Wolf Steel Napoleon S25 suit?
- Its 54,057 BTU/h peak output covers roughly 1,550–2,150 sq ft at the 25–35 BTU/h-per-square-foot rule of thumb — see the sizing calculator to adjust for your insulation and climate.
- The 2.51 cu ft firebox puts it in the mid-size home class.
- Rough fuel use: about 2.8 cords per season at the midpoint of its output range (8 burn-hours/day, 150-day season, 22 MMBtu/cord — see methodology).
- Certified burning Cord Wood — the test fuel closest to real-world firewood.
Similar wood stoves
- Wolf Steel Napoleon 2020-S (2.3 g/hr)
- Wolf Steel Napoleon S20 (2.3 g/hr)
- Wolf Steel Timberwolf 2200 (2.3 g/hr)
- Aduro AS H1 Hybrid (1.2 g/hr)
- Travis Industries 44 Elite NexGen-Hybrid (1.1 g/hr)
- FPI/Regency Fireplace Products F2450 (2.3 g/hr)
Frequently asked questions
Is the Wolf Steel Napoleon S25 EPA certified?
The Wolf Steel Napoleon S25 holds EPA certification number 266-20 but is no longer on the current certified list — it is previously certified, which usually means the model is out of production. Already-installed units are unaffected by that status in most jurisdictions.
What is the Wolf Steel Napoleon S25's emission rate?
The Wolf Steel Napoleon S25 is certified at 1.3 grams of particulates per hour (tested with cord wood). Real-world emissions depend heavily on fuel moisture and operation — the lab figure assumes seasoned fuel and correct air settings.
How many square feet can the Wolf Steel Napoleon S25 heat?
Roughly 1,550–2,150 sq ft, estimated from its 54,057 BTU/h peak output at 25–35 BTU/h per square foot. Insulation, climate, ceiling height, and floor plan move this figure substantially in both directions.
Does the Wolf Steel Napoleon S25 qualify for a federal tax credit?
No — the federal 25C credit for biomass stoves was terminated for property placed in service after December 31, 2025. The Wolf Steel Napoleon S25's certified efficiency is 72% HHV, which did not meet the credit's ≥75% HHV threshold while it existed. State and local incentive programs may still apply — check your state energy office and air district.
Sources
- cfpub.epa.gov (retrieved 2026-07-23)