Before opening the system to atmospheric pressure for repairs, what must a technician do first?

Before any opening of a refrigeration system to atmospheric pressure for repairs, it is essential to recover the refrigerant. This step is critical because refrigerants can be harmful to the environment and, in some cases, hazardous to human health. Releasing refrigerants into the atmosphere is not only illegal in many jurisdictions but can also contribute to global warming and ozone depletion.

By recovering the refrigerant, technicians ensure that the system is depressurized and safe to work on without the risk of introducing contaminants or further complications. Furthermore, recovering refrigerant allows for appropriate recycling or disposal, following regulations intended to protect the environment.

The other steps, while important in the repair process, do not directly address the need to manage refrigerants appropriately before exposing the system to atmospheric pressure.