What is the initial step before opening high- and low-side valves during passive recovery?

The correct answer is to connect the manifold gauge assembly to the system before opening the high- and low-side valves during passive recovery. This step is crucial because it allows for proper monitoring of refrigerant pressures and ensures that the recovery process is conducted safely and effectively.

When the manifold gauge assembly is connected, it provides a visual reference for both the low and high-side pressures in the system. This information is essential for determining the status of the refrigerant and ensuring that the recovery device is working correctly. Monitoring these pressures helps to avoid overfilling the recovery container and assists in understanding how much refrigerant is being extracted from the system.

Placing the recovery device in an ice bath, while it may help with recovery efficiency in certain circumstances, is not the foundational step required prior to opening the valves. Turning off the system completely is not necessary if you are performing passive recovery, as you only need to ensure that the recovery process does not compromise the system's integrity. Draining refrigerant into a proper container occurs after the manifold is connected and the valves are opened, not before. Thus, the connection of the manifold gauge is the primary step that sets up the recovery process.