<Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (August 2014) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (August 2014) (Learn how and when to remove this template message) </Td> </Tr> <P> A powered attic ventilator, or attic fan, is a ventilation fan which regulates the heat level of a building's attic by exhausting hot air . A thermostat is used to automatically turn the fan off and on, while sometimes a manual switch is used . An attic fan can be gable mounted or roof mounted . Additional vents are required to draw in fresh air as the hot air is exhausted . Attic fans are typically used in warmer months, when temperatures in an attic can exceed 120 ° F (49 ° C). A fan may be installed in an attic for the different purpose of cooling a whole house, venting hot air out via the attic; such fans are often called whole - house fans . </P>

Why is there a fan in the attic