1
ESCO Light Commercial Refrigeration
Exam , QUESTIONS WITH ACCURATE
ANSWERS | MULTIPLE CHOICES |!!
Commercial Refrigeration ESCO
Multiple compressors provide:
a. Positive oil return.
b. Lower humidity in high humidity locales.
c. Capacity control.
d. Zone control. - (ANSWER)c. Capacity control.
In a dry type (direct expansion) evaporator, liquid refrigerant must boil away as
close to the end of the coil as possible in order to:
a. Operate at high efficiency.
b. Ensure that frost does not accumulate.
c. Sub-cool the compressor.
d. Ensure proper oil return. - (ANSWER)a. Operate at high efficiency.
The difference between the temperature of the refrigerant boiling in the
evaporator and the temperature at the evaporator outlet is known as:
,2
a. Evaporator superheat.
b. Latent heat.
c. Evaporator sub-cooling.
d. Sublimation. - (ANSWER)a. Evaporator superheat.
An expansion device that is stuck open will cause:
a. Low suction pressure.
b. A starved evaporator.
c. Excessive superheat.
d. A flooded evaporator. - (ANSWER)d. A flooded evaporator.
Superheat measurements are best taken:
a. During a hot pull down.
b. At 8ºF to 12°F.
c. During defrost.
d. With the system operating at design conditions. - (ANSWER)d. With the system
operating at design conditions.
A technician is checking the superheat on a multi-circuit evaporator and finds one
of the circuits has a superheat that is higher than the others. This could be caused
by:
,3
a. A dirty coil.
b. A refrigerant overcharge.
c. Uneven air distribution.
d. A blocked distributor. - (ANSWER)d. A blocked distributor.
A TEV with an external equalizer is used on:
a. Evaporators with a high pressure drop.
b. Evaporators with a low pressure drop.
c. High temperature applications only.
d. All evaporators. - (ANSWER)a. Evaporators with a high pressure drop.
Dry type evaporators operate most efficiently with a superheat setting of
approximately:
a. 8ºF to 12°F.
b. 13°F to 19°F.
c. 20°F to 30°F.
d. 31°F to 40°F. - (ANSWER)a. 8ºF to 12°F.
, 4
An evaporator used to chill liquids is operating with a normal superheat setting,
but the system is not cooling the product properly. Which of the following is the
most likely cause?
a. Overcharge of refrigerant.
b. Undercharge of refrigerant.
c. The circulator.
d. The TEV. - (ANSWER)c. The circulator.
What time interval is required between each superheat adjustment?
a. Not less than 1 hour.
b. About 10-15 minutes.
c. At least ½ hour.
d. No time delay. - (ANSWER)c. At least ½ hour.
When measuring evaporator superheat on a commercial system that has a long
suction line, the pressure reading should be taken at the:
a. Compressor inlet.
b. Evaporator outlet.
c. Condenser outle
d. Receiver - (ANSWER)a. Compressor inlet.
ESCO Light Commercial Refrigeration
Exam , QUESTIONS WITH ACCURATE
ANSWERS | MULTIPLE CHOICES |!!
Commercial Refrigeration ESCO
Multiple compressors provide:
a. Positive oil return.
b. Lower humidity in high humidity locales.
c. Capacity control.
d. Zone control. - (ANSWER)c. Capacity control.
In a dry type (direct expansion) evaporator, liquid refrigerant must boil away as
close to the end of the coil as possible in order to:
a. Operate at high efficiency.
b. Ensure that frost does not accumulate.
c. Sub-cool the compressor.
d. Ensure proper oil return. - (ANSWER)a. Operate at high efficiency.
The difference between the temperature of the refrigerant boiling in the
evaporator and the temperature at the evaporator outlet is known as:
,2
a. Evaporator superheat.
b. Latent heat.
c. Evaporator sub-cooling.
d. Sublimation. - (ANSWER)a. Evaporator superheat.
An expansion device that is stuck open will cause:
a. Low suction pressure.
b. A starved evaporator.
c. Excessive superheat.
d. A flooded evaporator. - (ANSWER)d. A flooded evaporator.
Superheat measurements are best taken:
a. During a hot pull down.
b. At 8ºF to 12°F.
c. During defrost.
d. With the system operating at design conditions. - (ANSWER)d. With the system
operating at design conditions.
A technician is checking the superheat on a multi-circuit evaporator and finds one
of the circuits has a superheat that is higher than the others. This could be caused
by:
,3
a. A dirty coil.
b. A refrigerant overcharge.
c. Uneven air distribution.
d. A blocked distributor. - (ANSWER)d. A blocked distributor.
A TEV with an external equalizer is used on:
a. Evaporators with a high pressure drop.
b. Evaporators with a low pressure drop.
c. High temperature applications only.
d. All evaporators. - (ANSWER)a. Evaporators with a high pressure drop.
Dry type evaporators operate most efficiently with a superheat setting of
approximately:
a. 8ºF to 12°F.
b. 13°F to 19°F.
c. 20°F to 30°F.
d. 31°F to 40°F. - (ANSWER)a. 8ºF to 12°F.
, 4
An evaporator used to chill liquids is operating with a normal superheat setting,
but the system is not cooling the product properly. Which of the following is the
most likely cause?
a. Overcharge of refrigerant.
b. Undercharge of refrigerant.
c. The circulator.
d. The TEV. - (ANSWER)c. The circulator.
What time interval is required between each superheat adjustment?
a. Not less than 1 hour.
b. About 10-15 minutes.
c. At least ½ hour.
d. No time delay. - (ANSWER)c. At least ½ hour.
When measuring evaporator superheat on a commercial system that has a long
suction line, the pressure reading should be taken at the:
a. Compressor inlet.
b. Evaporator outlet.
c. Condenser outle
d. Receiver - (ANSWER)a. Compressor inlet.
