Before using a recovery unit, you should always check the ______ ______ _______, the oil level of the unit, and evacuate and recover any remaining refrigerant in the unit's receiver.

• A. service valve positions
• B. refrigerant cooling
• C. oil level
• D. receiver

Answer: (A)

Before using a recovery unit, the valves that control the service ports must be in the correct positions. Those service valve positions determine the path refrigerant takes: whether it flows from the system into the recovery unit and onward to the unit’s receiver, and how the unit is isolated during setup. If the valves aren’t set properly, refrigerant could leak to atmosphere, backflow into the system, or cause improper operation of the unit, leading to unsafe or ineffective recovery. After confirming the valve positions, you also check the oil level to protect the compressor, and evacuate any remaining refrigerant from the unit’s receiver to prevent releasing refrigerant when you start the unit. The other items don’t address establishing the correct flow path for the recovery process.