Attic fan repair or replacement. You can expect your attic fan to last between 10 - 15 years before needing its motor replaced. At Haas & Sons, we provide a 1-year labor warranty with our installations so that if there is a manufacturer's defect, we can replace it at no cost to you. The GAF Master Flow attic fans we install all come with a limited 10-year manufacturer warranty so if your motor happens to go out on year 5, there would only be the cost of labor to replace.