How should the HVAC system performance be evaluated?

The performance of an HVAC system is best evaluated by ensuring it maintains comfortable conditions within the space it serves. This involves assessing whether the system can effectively heat or cool the air to reach and sustain desired temperature levels, managing humidity, and providing adequate air circulation. A well-functioning HVAC system should provide a comfortable indoor environment while efficiently operating without excessive energy consumption.

Checking for unusual noises may indicate potential issues but doesn't directly measure performance. Adjusting temperature settings is part of operating the system but doesn’t assess its ability to effectively manage conditions. Inspecting the exterior grille can help identify obstructions or airflow issues, but it also does not provide a comprehensive evaluation of overall system performance or comfort levels. Thus, the best indicator of HVAC system performance is its ability to maintain a comfortable environment.