The mini split air conditioner's connecting line (line set) should be inspected periodically to ensure that it is not worn or damaged. Here are some recommended inspection frequencies:
Annual Inspection: It is generally recommended that a thorough inspection be performed at least annually. This can be done in conjunction with routine A/C system maintenance, such as before the start of summer or at the end of summer.
Environmental considerations: If the air conditioner is located near the ocean, salt, and moisture can accelerate corrosion of the piping, which may require more frequent inspections, such as every six months. More frequent inspections should also be considered in dusty or heavily polluted environments, as these conditions can accelerate wear and tear on piping and components.