Question 194Refrigeration & AC - 1st Asst/Chief

The correct answer is A) the bulb should be attached so that the pinched off tubing should be oriented down and the capillary tube running to the valve diaphragm should be oriented up. This is the correct orientation because it ensures that any condensation or liquid in the sensing bulb and capillary tube will drain back into the evaporator, allowing the thermal expansion valve to accurately sense the temperature and pressure at the evaporator outlet. Orienting the bulb and tubing in this way prevents liquid from collecting in the capillary tube, which could lead to improper valve operation. The other options are incorrect because they do not properly account for the need to orient the sensing bulb and tubing to allow for proper drainage and accurate temperature/pressure sensing by the thermal expansion valve.