Repairing a radon mitigation system often starts with checking the fan, which can wear out over time. I had to replace the motor on mine last month after it started making a grinding noise. The PVC piping also needed resealing where a joint had loosened. It's a straightforward job if you're handy, but proper venting is crucial to keep radon levels down. A simple manometer test confirmed the system was pulling negative pressure again. radon system repair 7