You are to fabricate a supply line to use when you pressure test newly installed refrigerant lines. A pressure regulator is the first device in the supply line. The second device down stream of the regulator is a pressure gage. A third device is required in the supply line after the regulator. What does the Code specify for the third device?

You are to fabricate a supply line to use when you pressure test newly installed refrigerant lines. A pressure regulator is the first device in the supply line. The second device down stream of the regulator is a pressure gage. A third device is required in the supply line after the regulator. What does the Code specify for the third device?