Oversized returns scale down noise and stress; adjusting go back plenums adds to furnace charges yet improves airflow

https://jaidenzqlw801.overblog.fr/2025/11/the-role-of-insulation-in-determining-your-home-s-heating-needs.html

Oversized returns reduce noise and strain; adjusting return plenums adds to furnace expenditures but improves airflow and comfort at lower fan speeds.