Emergency crews rushed to the Back Valley property near Victor Harbor after 7.30am following reports the man had suffered severe burns.
The 32-year-old man was seriously injured, prompting a major emergency response.
The man was treated at the scene before being loaded onto a stretcher and airlifted to Royal Adelaide Hospital.
It is believed the man was helping to light a heater when the flames exploded and swirled around him.
The man remains in serious but stable condition.