Installation starts with confirming the plan set at the estimate: equipment model, placement, electrical requirements, thermostat compatibility, and any duct or line set work included in the quoted price.
The old system is shut down, refrigerant is recovered per EPA rules, and the outdoor unit and indoor coil or air handler come out. New equipment is set level, lines are brazed under nitrogen to keep scale out of the system, and a deep vacuum pulls moisture and non-condensables before charging.
Commissioning matters more on heat pumps than on cooling-only systems because both modes need verification. The service professional checks charge, tests the reversing valve changeover, confirms defrost operation, sets auxiliary heat lockout appropriately for Temecula's mild winters, measures airflow, and walks you through the thermostat before leaving.