Grand Prairie Fire Department Battalion Chief Cal Timpf says a family used the grill Sunday night in the garage, to prepare food, then moved the grill inside to help heat the residence.
Timpf says four adults and an infant who were transported to a hospital are expected to recover.
Two paramedics who went into the home, before emergency personnel determined what had made the five residents sick, suffered carbon monoxide exposure and were treated at the scene.
The National Weather Service says temperatures in the Dallas area dipped below freezing early Monday, after being in the 40s on Sunday night.