The reason is that attic fans depressurize attics and can rob air conditioned air from the main body of the house greatly decreasing efficiency.
Attic exhaust fan temperature setting.
Most manufacturers and contractors recommend a temperature setting between 100 and 110 degrees fahrenheit.
If your attic soars above 100 degrees and reaches the 150 mark its time to consult professionals.
It essentially pulls that cooled air through cracks and crevices in the attic floor and also through holes that allow for wires and pipes.
Most manufacturers recommend setting your attic fan thermostat between 105 115 degrees and monitoring how often and how long the fan runs to adjust the setting for your home.
Attic ventilators generally turn on between 90 and 110 degrees fahrenheit.
In particularly hot climates set the temperature higher to keep the fan from running for extended periods of time.
Most attic fans operate with a thermostat that automatically turns the fan on and off based on a temperature the homeowner sets.
When the temperature within the attic reaches a set point the fan will turn on and start venting the heated air cooling the attic space.
When it comes to adjusting the thermostat of your attic s fan it s best to adjust it to approximately 90 to 95 degrees.
That said attic fans are not the best choice for cooling attics especially if you have central air conditioning.
Likewise adjustable thermostats will shut the fan off.