The 49-year-old woman was found on the floor of the locked bedroom after crews doused the flames. The room was sealed up with no ventilation. She was declared dead at the scene.
Los Angeles Fire Department spokesman Brian Humphrey said the cause of the fire remained under investigation, although a preliminary report indicated the fire may have been sparked by charcoal briquettes on a metal tray being improperly used as a heating device.
Firefighters believe it wasn't the fire that killed the woman, but a lack of oxygen in the smoldering room.
"This is extremely dangerous. This type of heating device will use up all the oxygen inside a room not to mention give off carbon monoxide. We call it the silent killer," said Los Angeles City Fire Batt. Chief Trevor Richmond.
The home was not equipped with smoke alarms, fire sprinklers or a carbon monoxide detector.
Neighbors said the gas to the woman's home had been shut off several weeks ago. They identified the victim as Janice Jones. They said she lived alone and mostly stayed to herself.
No other injuries were reported.
The fire, which was put out less than 12 minutes after the initial 911 call, caused an estimated $15,000 damage to the wood frame and stucco home and its contents, Humphrey said.
With more cold weather on the way, firefighters are trying to spread the warning about using hot coals inside a home. It will heat the air but with a potentially deadly dose of carbon monoxide.