How it works

EPA testing measures particulate emissions during a defined burn protocol covering startup, high burn, and low burn phases. To pass, the appliance must average below 2.5 g/hr across the test cycle. Catalytic combustors and secondary-burn tube systems are the two primary technologies for achieving compliance, with manufacturer hybrid systems combining both for additional emissions reduction.

Phase 2 stoves typically deliver 70 to 80 percent thermal efficiency, compared to 30 to 50 percent for older non-EPA stoves. Cleaner combustion also produces less creosote, reducing chimney maintenance frequency and chimney fire risk. Sweeps inspect Phase 2 stoves with the same maintenance schedule as older units but typically find lighter deposits and longer intervals between major service.

DFW context

DFW wood-stove installations since 2020 have all been EPA Phase 2 by code requirement, with major brands including Lopi, Pacific Energy, Regency, Quadra-Fire, and Hearthstone available through TSE for consultation, sales, and installation. Replacement of pre-EPA stoves with Phase 2 units is encouraged by air-quality regulators in some Texas regions, and TSE coordinates these conversions including necessary chimney lining work.

Related terms

• [Catalytic combustor](/glossary/catalytic-combustor/)
• [Secondary burn](/glossary/secondary-burn/)
• [Wood-burning insert](/glossary/wood-burning-insert/)
• [UL 1482](/glossary/ul-1482/)

Sources

• EPA NSPS 40 CFR Part 60 Subpart AAA
• UL 1482 Standard for Solid-Fuel Type Room Heaters
• NFPA 211 (2024), Section 11