Buck Stove 42″ ZCBBXL Vent-Free Fireplace with Oak Logs — Propane

What “vent-free” means

This unit burns gas with no chimney or flue, so all combustion products stay in the room. It is built and listed to ANSI Z21.11.2 and carries an oxygen-depletion sensor (ODS) that shuts off the gas if the oxygen level in the room falls.

Model fuel-gas code caps a vent-free heater at 40,000 BTU/h, limits the combined input of all unvented appliances to 20 BTU/h per cubic foot of room volume, and does not allow it to be the sole source of heat for a home. Your room size genuinely matters here.

Where it is restricted

• California — state law prohibits the sale of unvented heaters designed for use inside a dwelling. Vented decorative gas logs are expressly exempt.
• Minnesota — unvented room heaters and unvented decorative appliances may not be installed in any dwelling or occupancy. No exceptions in the rule.
• Wisconsin — permanently installed gas-fired unvented heating appliances may not be installed; unvented space heaters are separately prohibited in one- and two-family dwellings.
• Massachusetts — allowed only with a permit from the head of the fire department, inspection by the fire department and the gas inspector, a 40,000 BTU cap per room, a CO detector in the room, and never as the primary heat source.
• Manufactured (HUD-code) homes, anywhere in the US — federal rule requires fuel-burning heating appliances to be vented to the outside.