Air filter replacement in your AC unit is crucial in maintaining air quality and system efficiency. Generally, we recommend replacing filters every 30 to 90 days. This can vary based on factors such as the type of filter, the air quality in your area, and specific household conditions, such as the presence of pets or individuals with allergies. More frequent replacements can help provide better airflow and efficiency, contributing to a healthier living environment and potentially lowering energy costs by maintaining your AC's performance.