As the weather was cooling down, a Missouri father turned the furnace on in his family’s home that they had owned for a short time.  That was the first time they had used the furnace that winter.  By the next evening, the man and his daughter were found dead and his wife and son had suffered severe carbon monoxide poisoning with resulting permanent brain damage.  Post-accident inspections found significant quantities of rust on the furnace’s burners that blocked the flame ports on the burners, disrupting normal gas flow and causing incomplete combustion.  This condition resulted in the production of carbon monoxide in lethal amounts.