Buddy had his AC go out. Compressor failed and put debris throughout the system. AC shop replaced everything, said they flushed it. Worked for a few days, failed again. More debris. After the third failure took it to another place. Said residual debris that can not be gotten out caused the failure. They replaced everything. Works fine after a year. Could be that he was unlucky? I do know of many home AC units that have failed and a flush and repair that has led to long term service. Internals are different.