A technician is recovering R-134a refrigerant from a heavy-duty excavator's A/C system. The system's low-side pressure gauge reads 200 kPa when the recovery machine is connected and running. Which of the following is the most appropriate next step according to environmental regulations and best practices?

Question: A technician is recovering R-134a refrigerant from a heavy-duty excavator's A/C system. The system's low-side pressure gauge reads 200 kPa when the recovery machine is connected and running. Which of the following is the most appropriate next step according to environmental regulations and best practices?

Answer options: ✅ Continue evacuating until the system reaches a deep vacuum (e.g., -95 kPa or 29.5 inHg vacuum) to remove all refrigerant and moisture.

• Stop the recovery as soon as the pressure drops to 0 kPa, indicating all liquid refrigerant has been removed.
• Add new R-134a to help push the remaining refrigerant out of the system for a faster recovery.
• Disconnect the recovery machine, as 200 kPa indicates sufficient refrigerant has been recovered for a safe repair.

Correct answer: Continue evacuating until the system reaches a deep vacuum (e.g., -95 kPa or 29.5 inHg vacuum) to remove all refrigerant and moisture.

Explanation: According to Canadian environmental regulations and best practices for refrigerant recovery (e.g., Environment and Climate Change Canada guidance), systems must be evacuated to a deep vacuum after refrigerant removal to ensure all traces of refrigerant, non-condensable gases, and moisture are removed before servicing, protecting both the environment and system integrity.