The answer to 'when to service evaporator coil' is that you should service the evaporator coil in your HVAC system at least once a year, or more often if you notice reduced cooling performance or higher energy bills. The evaporator coil is responsible for absorbing heat from the air in your home, so keeping it clean and functioning properly is crucial for efficient and effective cooling.
During a service visit, an HVAC technician will thoroughly inspect the coil, clean it if necessary, and check for any signs of damage or wear. They may also check the refrigerant levels and the overall operation of the system to ensure it is running at peak efficiency.