This document discusses quality installation of high efficiency heating and cooling systems. It outlines common installation issues like improper equipment sizing, duct design problems, duct and air leakage, and improper filter and equipment setup. These issues can significantly impact a system's performance and efficiency. The document emphasizes that proper static pressure and temperature measurements are important diagnostics to evaluate overall system performance and identify airflow restrictions or other problems. A quality installation is key to ensuring a system can deliver close to its full rated efficiency and performance.