When it comes to the temperature setting of an attic fan, it's best to adjust it to a temperature of 90 to 110 degrees Fahrenheit. In general, most homeowners should set the attic fan temperature between 90 and 110 degrees Fahrenheit. Typically, set the attic fan to a temperature between 95 and 115 degrees. However, it is important to set the fan to a higher temperature than the ambient outside temperature to prevent the fan motor from burning out.
Contrary to intuition, you should place the attic fan in a warm climate between 90 and 110 degrees. Most attic fans have a thermostat that tells the fan to turn on and off once the attic reaches a specific temperature. The most recommended temperature setting for an attic fan in summer is 90 to 110 degrees Fahrenheit. Ideally, the temperature setting should be equal to the outside temperature, and this is the thermostat setting that most HVAC technicians recommend.
Thermostatically controlled fans require adjustments a couple of times a year. During the summer, the fan should operate at any time when the attic temperature is above the desired comfort level for indoor living quarters. For example, if the air conditioner thermostat is set to 74 degrees, the attic fan could be set to 75 degrees. During winter, the attic fan thermostat should be adjusted below freezing point to prevent ice from building up on the roof.
Using a fan to take warm air out of your attic and replace it with cool air from outside, solves the problem of ice buildup. Read the following subsections to learn how to decide the approximate frequency with which you should run your attic fan. It's usually a matter of reviewing the fan owner's manual or perhaps the fan housing to understand the cubic feet per minute it blows. Calculating the volume of your attic is a process that varies depending on the type of attic you have.
This could be a good idea even if you can find the strength of your fan, as it is rare for a fan to pull the CFM as advertised. If ice buildup isn't a problem for you (which shouldn't be in a well-insulated attic), then there's less reason to run the attic fan in winter. If you take notes on how often you run the fan and the heat from the ceiling adjacent to the attic, you will develop an idea of how often you should run the fan. Running attic fans on the right schedule improves the efficiency of the ventilation system by providing a more comfortable and energy efficient home.
If you want to turn on the attic fan at a lower temperature, change the thermostat setting accordingly, however, for best results, you should be on par with the outside temperature. You'll know that you've managed to understand how often you should use the attic fan when you realize that the rooms adjacent to the attic are cooler and more comfortable. If the thermostat is a little high, natural convection cooling from the attic ventilation system will lower the temperature the rest of the way in a reasonably short amount of time after the fan shuts down. To test an attic fan, simply set the temperature dial above the current attic temperature.
Most other home problems that could be solved with attic fans are best solved with better insulation and air sealing.