Question 155Refrigeration/AC - 1st Asst/Chief70% to pass
An obstructed expansion valve may be indicated by an incompletely cooled evaporator and what other symptom?
AI Explanation
The correct answer is A) frosting at the evaporator inlet.
An obstructed expansion valve can cause incomplete cooling of the evaporator, leading to frosting at the evaporator inlet. This is because the restricted expansion valve reduces the flow of refrigerant into the evaporator, resulting in an uneven temperature distribution across the evaporator coil.
The other options are incorrect because:
B) Frosting at the suction side of the compressor is more indicative of a problem with the compressor or low refrigerant charge.
C) A higher than normal discharge pressure is more likely caused by a problem with the condenser or excessive refrigerant charge.
D) A decrease in the amount of frosting across the drier is not a symptom of an obstructed expansion valve, as the drier is located upstream of the expansion valve.
Related Questions
#153 If the superheat value of the thermostatic expansion valve is adjusted too high, what would be the result? #154 Vapor bubbles present in the liquid upon arrival to the thermal expansion valve in a refrigeration system may cause erosion of the expansion valve's needle and seat. This, in turn, could cause what condition? #156 Moisture entering a typical refrigeration system will most likely produce what effect? #157 A small obstruction at the thermostatic expansion valve inlet will result in which of the following conditions? #158 If the superheat setting of a thermostatic expansion valve is set too low, what would be the result, assuming that the system has a single evaporator?