An elderly couple have been found dead in their bedroom after their heater was estimated to have reached 538C (1,000F).
Joan Littlejohn, 84, and Glennwood Fowler, 82, were found in their South Carolina home on Saturday evening, with police recording the temperature of the property sitting at around 49C (120F) even 20 minutes after they had opened the windows and doors to let colder air in.
The discovery came three days after the couple had complained that they were having trouble with their heating.
Police said the couple told their family on Wednesday that their heating system and water heater were not working, so family members visited and thought they had fixed the problem.
The family members contacted police three days later, having not heard from the couple since their visit.
A paramedic found the bodies in the bedroom after entering through an unlocked window, authorities said.
The paramedic couldn’t accurately measure the body temperatures of the couple, because of the device’s maximum measurement of 41.1C (106F).
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They also checked for carbon dioxide levels, which weren’t particularly high, according to the police report.
Firefighters said the heater in the basement looked like it was on fire before they turned it off on Saturday and estimated its internal temperature at 538C (1,000F), police said.
The first officer on the scene said the home’s thermostat was working again and had come down to 35.5C (96F) by the time he left two-and-a-half hours later.
Investigators plan a post-mortem and other tests to determine exactly what killed the couple, Spartanburg County coroner Rusty Clevenger said in a statement.