A factory charge refers to the precise amount of refrigerant pre-loaded into an outdoor unit by the manufacturer at the factory. This charge is typically designed to accommodate a standard Line Set length of 15 to 25 feet depending on the specific model. When installing ACIq systems, it is vital to check the manual to see if your specific line length requires additional refrigerant. If your installation involves a very long run, a technician must add more gas to ensure the system reaches its rated efficiency. Conversely, if the run is very short, some refrigerant may need to be recovered to prevent liquid slugging. Most Ductless Mini Splits come with a factory charge that makes the initial setup faster and more reliable for the installer. Having a correct charge is the only way to guarantee that your Mobile Home Complete System meets its advertised SEER2 ratings. It is the baseline for all subsequent pressure and temperature measurements during the commissioning process.