Which of the following statements describes the accepted method for testing a thermostatic expansion valve?

Correct Answer: Option D — Place the sensing bulb in ice water and then warm by hand. Observe flood-through and temperature change at the suction line.

Testing a thermostatic expansion valve requires altering the bulb temperature to observe system response. Chilling the bulb in ice water decreases superheat opening the valve, while warming by hand increases superheat, verifying proper valve modulation and flood-through behavior.