The total amount of refrigerant that should be added and recovered for the two refrigerant gauges in the image is 10 pounds.
This can be determined by looking at the Liquid Line gauge, which shows a pressure of 200 psi at a temperature of 86°F. According to the R-410A refrigerant chart, this pressure corresponds to a saturation temperature of 95°F.
However, the Suction Line gauge shows a pressure of 0 psi at a temperature of 55°F. This indicates that the system is undercharged, as the saturation temperature of R-410A at 0 psi is 17°F.
To recharge the system, refrigerant would need to be added until the Suction Line gauge shows a pressure of 60 psi, which corresponds to a saturation temperature of 55°F. At this point, the system would contain a total of 10 pounds of refrigerant.
To recover refrigerant from the system, the procedure would be reversed. The refrigerant would be removed from the system until the Suction Line gauge shows a pressure of 0 psi. At this point, all of the refrigerant would have been recovered from the system.