Firefighters were called to extinguish a small fire in an extractor fan at Fowey at 8.30pm yesterday.
Two appliances from Fowey Fire Station attended the fire at a property in Fore Street.
The fire service said: "On arrival the crews found a fire in an extractor fan which had extinguished prior to their arrival. The fire crew used thermal image camera and small tools to make the scene safe. The cause is believed to be accidental."