The components that comprise the solar system, including the solar panels, inverters, mounting hardware, monitoring devices, the electrical wiring and devices, and storage batteries are reliable devices which have no moving parts, no user serviceable parts, and require no user maintenance.
The only item that may require attention is the solar panels the may require cleaning. Over time, and depending on your environment, the panels may become coated or covered with dirt and debris. There may also be events, such as nearby fires, that may coat the panels with soot, sap from nearby trees, or bird droppings. Usually, in most parts of the country, normal rainfall will keep the solar panel clean. If you are aware of such events occurring or if you notice a constant drop in production for no obvious reason (e.g. cloudy weather), then the panels should be visually checked and cleaned, if required.