How it works

The insert slides into the existing fireplace opening, with an insulated stainless steel liner connected from the unit’s exhaust collar up through the existing flue to the chimney top. A faceplate or surround seals the gap between the insert and the fireplace opening, preventing room air from being pulled into the chimney. The unit’s secondary combustion technology, typically a catalytic combustor or a non-catalytic baffle, burns smoke at high temperature, extracting maximum heat and minimizing emissions.

Wood-burning inserts require seasoned hardwood at less than 20 percent moisture content for proper operation. Owners load the firebox, set the air controls for desired burn rate, and monitor with a flue thermometer. The closed firebox retains heat against the home rather than losing it up the chimney. Sweeps inspect the catalytic or baffle system, gaskets, glass, and liner annually, with full creosote removal as part of the service.

DFW context

Wood-burning inserts in DFW are most popular among committed wood-heat enthusiasts in rural and acreage properties around Denton, Wise, and Parker counties, where free firewood from agricultural operations offsets utility costs. TSE installs major brands including Lopi, Regency, Quadra-Fire, and Pacific Energy, with insulated stainless reline as standard. The mild Texas winter limits wood-heat demand for most owners, but committed users find inserts deliver reliable supplemental heat.

Related terms

• [Insert](/glossary/insert/)
• [EPA Phase 2 wood stove](/glossary/epa-phase-2-wood-stove/)
• [UL 1482](/glossary/ul-1482/)
• [Catalytic combustor](/glossary/catalytic-combustor/)
• [Secondary burn](/glossary/secondary-burn/)

Sources

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