Charging charts are sometimes used to charge the system. These charts are usually attached to the unit or included in the manufacturer’s service instructions. Use the charts as directed by the manufacturer to charge the unit. Also, be sure that the indoor airflow CFM is the same as that specified on the charts.
If charging a heat pump using a chart, it must be charged in the cooling mode. Be sure that the chart you use for charging is a cooling charging chart. Never use the heating cycle check chart to add or remove a refrigerant charge.
