Steel Tech G Series G400G400s
Steel Tech G Series G400G400s is a non-catalytic hydronic heater from Steel Tech certified at 9 g/hr particulate emissions with 74% HHV efficiency (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 | hydronic-heater |
|---|---|
| Combustion technology | Non-Catalytic Stove |
| Certified fuel | Cord Wood |
| Covered model numbers | G Series G400G400s |
| Emission rate | 9 g/hr |
|---|
| Efficiency (HHV) | 74 % |
|---|
| Heat output (high) | 350000 BTU/h |
|---|
| 25C tax credit eligible (≥75% HHV) | No |
|---|---|
| 2020 NSPS compliant | No |
| Currently in production | No |
What space does the Steel Tech G Series G400G400s suit?
- Certified burning Cord Wood — the test fuel closest to real-world firewood.
Similar hydronic heaters
Frequently asked questions
Is the Steel Tech G Series G400G400s EPA certified?
The Steel Tech G Series G400G400s holds EPA certification number n/a 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 Steel Tech G Series G400G400s's emission rate?
The Steel Tech G Series G400G400s is certified at 9 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.
Does the Steel Tech G Series G400G400s 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 Steel Tech G Series G400G400s's certified efficiency is 74% 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)