Long run time is not automatically a failure
On a very hot afternoon, a correctly operating system may run longer to offset the home's heat gain. The more important clues are whether indoor temperature remains reasonably stable, humidity feels controlled, and performance has changed from normal.
Check airflow and heat gain
- Replace a dirty filter and keep returns and supplies clear
- Close exterior doors and windows and use blinds where direct sun is strong
- Record indoor and thermostat temperatures and the time of day performance declines
Request an evaluation when
- The home never approaches the thermostat setting
- Run time or energy use changed suddenly
- Airflow is weak, the coil ices, or the system cycles off on a breaker