Performed heating tune up service on all 3 systems checking all electrical components, refrigerant balance, cleaning of all furnace components, treatment of drains, performance of full combustion analysis, testing of unit start up, operation, shutdown. Customer complaint about mini split dehumidification during summer months causing high humidity when in dry mode. Tested minisplit in both heat and cool finding all electrical components and refrigerant balance within manufacturer's specifications. Referenced system manual to attempt to change dry mode settings. Will recommend a return in spring to check dry mode operation as it does not want to dehumidify without a cooling load on the building. Upstairs may require additional dehumidification but can be more accurately tested when outdoor temperatures and humidity are higher.