Daikin single zone mini split heat pump almost out of refrigerant Performed visual leak search All flare fitting connections in the line set are dry and clean Saw no signs of oil on indoor or outdoor coils Added refrigerant and dye System cooling normally As I was packing up my tools and the unit was off, I heard hissing Used soap bubbles to locate a leak on the outdoor coil Will need to replace the outdoor coil under Daikin factory parts warranty. Replaced outdoor coil. System operating normally at this time. .