How can I check if the mini split line set is well sealed?

Checking that the mini split air conditioner's connecting line (line set) is well sealed can be accomplished by following a few steps:

• Visual Inspection: Begin with thoroughly inspecting the line's exterior, looking for significant damage, cracks, or unusual marks, such as oil stains, which could be signs of a leak.
• Soapy Water Inspection: Apply soapy water or a special foam leak detector to all welded joints, threaded connections, and possible leak points. Then turn on the system, allow it to run, and watch for bubbles to form in the area where the soapy water was applied. If you see bubbles forming, this usually means there is a leak in the area.