Question 187Refrigeration/AC - 1st Asst/Chief70% to pass
The coil temperature measured at the expansion valve sensing bulb of an operating system is 10°F. The low side pressure with the compressor running as shown on the gauge illustrated indicates 15 psig. What adjustments or changes, if any, should be made to the system? Illustration GS-RA-16
AI Explanation
The correct answer is C) The expansion valve should not be adjusted, as the degree of superheat is within the accepted range.
This is the correct answer because the low side pressure of 15 psig and the coil temperature of 10°F indicates that the system is operating with a proper degree of superheat, which is typically between 6-12°F. Adjusting the expansion valve is not necessary, as the system is functioning within the acceptable parameters.
The other options are incorrect because they suggest issues that are not indicated by the given information. Cleaning the evaporator coils or changing the filter drier are not necessary based on the provided data, and the liquid line strainer does not need to be cleaned if the system is operating properly.
Related Questions
#185 What maintenance may be carried out on a thermostatic expansion valve? #186 Which of the listed statements describes the method used to determine the amount of superheat present in the suction gas leaving the evaporator coil? Illustration GS-RA-16 #188 Of the various possible methods shown in the illustration, which is the correct method of attaching a TXV feeler bulb to a large line (7/8" and larger) with a horizontal run? Illustration GS-RA-50#189 Expansion valve maintenance should include which of the following procedures? #190 A thermostatic expansion valve is properly controlling evaporator superheat. Adjusting this valve to lower the evaporator superheat setting will result in which of the following?