The answer to 'when to service ductless system' is that ductless mini-split systems should be serviced at least once a year, typically in the spring before heavy cooling season. This maintenance helps ensure the system is operating efficiently and can catch any potential issues before they become major problems.
During an annual service, a technician will clean the indoor and outdoor units, check refrigerant levels, inspect electrical connections, and test the system's overall performance. They may also recommend replacing air filters, cleaning the condensate drain, or addressing any other maintenance needs.