Question 194Refrigeration/AC - 1st Asst/Chief70% to pass
Concerning the proper installation of the sensing bulb of a thermal expansion valve that is attached to the evaporator tail coil on a horizontal run, which statement is true?
AI Explanation
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.
Related Questions
#192 Which of the following statements describes the accepted method for testing a thermostatic expansion valve? #193 If the evaporator coil horizontal return line of a container refrigeration system is less than 0.875" #195 Which of the installation steps listed is necessary for the proper operation of the thermostatic expansion valve? #196 Technicians servicing small refrigeration appliances can employ what type of recovery equipment? #197 Which recovery procedure should be used to minimize the loss of oil from the system during the recovery of refrigerant from small appliances such as a water cooler?