Some refrigeration systems are designed to be installed using a pre-charged line set. This normally allows for quicker installation and reduces the risk of non-condensables entering the system, saving both time and money on a typical installation.
These line sets use a quick connect coupling assembly, which allows refrigerant to be trapped in the tubing with the line set connected and then released by simply tightening a nut. However, using this type of line set is not without complications, and if installed incorrectly, it can lead to some major issues.