Heatmor Manufacturing 400-4S

Heatmor Manufacturing 400-4S is a non-catalytic hydronic heater from Heatmor Manufacturing certified at 10.7 g/hr particulate emissions with 76% 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.

General
Appliance type hydronic-heater
Combustion technology Non-Catalytic Stove
Certified fuel Cord Wood
Covered model numbers 400-4S
Emissions
Emission rate 10.7 g/hr
Efficiency
Efficiency (HHV) 76 %
Heat output
Heat output (high) 400000 BTU/h
Certification
25C tax credit eligible (≥75% HHV) Yes
2020 NSPS compliant No
Currently in production No

What space does the Heatmor Manufacturing 400-4S suit?

Similar hydronic heaters

Frequently asked questions

Is the Heatmor Manufacturing 400-4S EPA certified?

The Heatmor Manufacturing 400-4S 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 Heatmor Manufacturing 400-4S's emission rate?

The Heatmor Manufacturing 400-4S is certified at 10.7 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 Heatmor Manufacturing 400-4S 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 Heatmor Manufacturing 400-4S's certified efficiency is 76% HHV, which met 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.

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