The answer to 'why is my air filter making loud noise' is that a clogged or dirty air filter can cause it to make loud noises. When the air filter becomes too dirty or clogged, it restricts airflow through the HVAC system, which can create vibrations and rattling sounds as the blower fan struggles to push air through the restricted filter.
This is a common problem that can be easily fixed by simply replacing the air filter. Homeowners should check and replace their air filters every 1-3 months, depending on usage and home environment. Replacing a dirty filter with a clean one should eliminate the loud noises.