You'll find direct vent model natural gas fireplace inserts as well as the amazingly productive ventless models. These natural gas fireplace inserts are available in a giant array of styles and sizes, too, so everyone can find exactly what they want. You truly do get the best of both worlds with these amazing natural gas fireplace inserts.
I want to convert my wood burning fireplace into a vent-less natural gas unit. Do I need to purchase an insert? Can we just plumb a gas line to the fireplace buy the gas logs and the damper latch hardware?
To answer your question, a locally-licensed plumber will need to run a 1/2" cast iron pipe stub into the fireplace opening per both local and national fuel gas code, in addition to a manual shutoff valve a.k.a. key valve on the wall or floor adjacent to the fireplace opening. When installing a ventless system inside any wood fireplace, you would simply close the damper.