| The most cost-effective method of recovering refrigerant from a low pressure chiller with more than 500 lbs of refrigerant and to meet EPA requirements is to recover the refrigerant using what protocol? |
| A) vapor recovery using a vacuum pump based recovery unit followed by liquid recovery using a liquid pump |
| B) recovery using a vacuum pump based vapor recovery machine only |
| C) recovering using a liquid pump only |
| D) liquid recovery using a liquid pump, followed by vapor recovery using a vacuum pump based recovery unit |
