Question 186Refrigeration/AC - 1st Asst/Chief70% to pass
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
AI Explanation
The correct answer is D.
The method used to determine the amount of superheat present in the suction gas leaving the evaporator coil is to note the low side pressure, determine the corresponding saturation temperature, and subtract it from the temperature measured with a thermometer at the thermostatic expansion valve sensing bulb. This is because the difference between the saturation temperature and the actual temperature of the suction gas is the amount of superheat.
The other options are incorrect because they do not correctly describe the method for determining superheat. Option A measures the temperature at the compressor suction inlet instead of the thermostatic expansion valve sensing bulb, and option B subtracts the wrong temperature. Option C adds the saturation temperature instead of subtracting it.
Related Questions
#184 When a thermostatic expansion valve is installed in a refrigerated container unit, the sensing bulb almost always requires insulation. Why is this so? #185 What maintenance may be carried out on a thermostatic expansion valve? #187 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 #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?