Replacing the fan in your radon mitigation system is one of those jobs you hope to never have to do, but it's critical for keeping radon levels low in your home. The old unit had been running for years and started making a worrying hum. I turned off the power, disconnected the ductwork, and unbolted the fan from the wall. The new one fit perfectly, but I had to re-caulk around the exterior vent to ensure no leaks. Firing it back up, the steady hum of the new fan is a huge relief—it's pulling ai… radon fan replacement 10