Question 189Refrigeration & AC - 1st Asst/Chief

The correct answer is D) All of the above. Expansion valve maintenance should include all of the procedures listed: ensuring the thermal bulb is in good contact with the suction line and insulated, checking that the thermal bulb is in the proper location, and cleaning any in-line strainers as necessary. These steps are important to ensure the proper functioning of the expansion valve, which regulates the flow of refrigerant in a refrigeration or air conditioning system. Performing these maintenance tasks helps prevent issues like poor cooling performance or system failure.