Plan to schedule annual HVAC system maintenance once in the spring for your cooling equipment and again in the fall for your heating system. If you have a heat pump, the combined heating/cooling system should receive maintenance twice a year.
Plan to perform a few maintenance tasks of your own between these formal visits. The following DIY tasks help keep your equipment running smoothly until the next professional visit:
Change the HVAC air filter every month. Some units have an indicator light that tells you when the filter is beginning to become clogged and blocking airflow.
Remove debris from around the outdoor unit.
Hose down the outdoor unit when dirt begins to accumulate on it.
Trim back foliage to at least 18 inches from the outdoor unit.
Keep supply and return registers unblocked by drapes, rugs or furniture.