HVAC Excellence Test Commercial AC
Complete Questions And Answers
Condenser fan-cycling controls have the same action as a low-pressure control except it: CORRECT ANSWERS Is used to control the high pressure also.
A sling psychometer is used to measure CORRECT ANSWERS wet and dry bulb temperature.
Some compressors are fitted with an unloading device to CORRECT ANSWERS provide variable capacity.
Compressor net oil pressure is determined by CORRECT ANSWERS oil pump discharge pressure minus suction pressure.
A compressor is operating with a discharge pressure of 185.3 psig and a suction pressure of 25.3 psig. The compression ratio (pumping ratio) is: CORRECT ANSWERS 5:1
Got Gas Bypass refers to a method of CORRECT ANSWERS preventing low suction pressure.
The capacity of a cooling tower depends on the CORRECT ANSWERS Entering air wet
bulb temperature.
Wet bulb depression is the difference CORRECT ANSWERS between wet bulb and dry bulb temperatures.
Refrigerant in the suction light should be slightly superheated in order to CORRECT ANSWERS insure liquid refrigerant does not enter the compressor.
On split system installations, the suction line should be pitched towards the compressor at least CORRECT ANSWERS One inch per ten feet.
The most reliable and safest method of field charging a system is to charge CORRECT ANSWERS by weight according to the manufacturer's specifications
Approximately how much airflow is required across the evaporator per ton of cooling capacity? CORRECT ANSWERS 350-450 cfm per ton
the amount of heat absorbed in the evaporator is equal to the heat CORRECT ANSWERS given off by the condenser minus the heat of compression. If a TEV sensing bulb has lost all of its charge, what effect would this have on the air conditioning system? CORRECT ANSWERS It would cause low side pressure to increase.
A decrease in water flow, when using a water - cooled condenser CORRECT ANSWERS increases the power consumption of the compressor.
High compressor operating temperatures can be caused by CORRECT ANSWERS high compression ratios.
What is the purpose of a distributor? CORRECT ANSWERS It evenly feeds refrigerant to the evapaorator
Upon investigation of a "no cooling" complaint, the technician finds that the blower motor of the air handler has open windings. One week ago, this same unit was found to have a broken belt caused by a worn drive pulley. Both the belt and pulley were replaced at that time. The technician decides to replace the motor and; CORRECT ANSWERS adjust the drive pulley to decrease amp draw.
An air conditioning unit has a suction line iced up to the compressor. What would this be
an indication of? CORRECT ANSWERS A low refrigerant charge.
Depending on the application, suction lines may be ______ to assure proper oil return. CORRECT ANSWERS trapped
When sizing a cooling tower, it is important to know that one pound of evaporating water
can absorb CORRECT ANSWERS 970 BTU's
Polvolester oils CORRECT ANSWERS have more atmospheric moisture than mineral oil.
The clearance space in a reciprocating compressor CORRECT ANSWERS has an effect on compressor capacity.
Which of the following will cause a major change in compressor capacity when retrofitting to another type of refrigerant? CORRECT ANSWERS Discharge pressure
A disadvantage to the reciprocating compressor over other designs is CORRECT ANSWERS some refrigerant will always remain in the clearance space.
The flow switches of a chiller's control system CORRECT ANSWERS Allow refrigeration
system operation only when the water circulating pumps are energized
What is used to control the flow of water on a water-cooled condenser? CORRECT ANSWERS A water regulating valve
Complete Questions And Answers
Condenser fan-cycling controls have the same action as a low-pressure control except it: CORRECT ANSWERS Is used to control the high pressure also.
A sling psychometer is used to measure CORRECT ANSWERS wet and dry bulb temperature.
Some compressors are fitted with an unloading device to CORRECT ANSWERS provide variable capacity.
Compressor net oil pressure is determined by CORRECT ANSWERS oil pump discharge pressure minus suction pressure.
A compressor is operating with a discharge pressure of 185.3 psig and a suction pressure of 25.3 psig. The compression ratio (pumping ratio) is: CORRECT ANSWERS 5:1
Got Gas Bypass refers to a method of CORRECT ANSWERS preventing low suction pressure.
The capacity of a cooling tower depends on the CORRECT ANSWERS Entering air wet
bulb temperature.
Wet bulb depression is the difference CORRECT ANSWERS between wet bulb and dry bulb temperatures.
Refrigerant in the suction light should be slightly superheated in order to CORRECT ANSWERS insure liquid refrigerant does not enter the compressor.
On split system installations, the suction line should be pitched towards the compressor at least CORRECT ANSWERS One inch per ten feet.
The most reliable and safest method of field charging a system is to charge CORRECT ANSWERS by weight according to the manufacturer's specifications
Approximately how much airflow is required across the evaporator per ton of cooling capacity? CORRECT ANSWERS 350-450 cfm per ton
the amount of heat absorbed in the evaporator is equal to the heat CORRECT ANSWERS given off by the condenser minus the heat of compression. If a TEV sensing bulb has lost all of its charge, what effect would this have on the air conditioning system? CORRECT ANSWERS It would cause low side pressure to increase.
A decrease in water flow, when using a water - cooled condenser CORRECT ANSWERS increases the power consumption of the compressor.
High compressor operating temperatures can be caused by CORRECT ANSWERS high compression ratios.
What is the purpose of a distributor? CORRECT ANSWERS It evenly feeds refrigerant to the evapaorator
Upon investigation of a "no cooling" complaint, the technician finds that the blower motor of the air handler has open windings. One week ago, this same unit was found to have a broken belt caused by a worn drive pulley. Both the belt and pulley were replaced at that time. The technician decides to replace the motor and; CORRECT ANSWERS adjust the drive pulley to decrease amp draw.
An air conditioning unit has a suction line iced up to the compressor. What would this be
an indication of? CORRECT ANSWERS A low refrigerant charge.
Depending on the application, suction lines may be ______ to assure proper oil return. CORRECT ANSWERS trapped
When sizing a cooling tower, it is important to know that one pound of evaporating water
can absorb CORRECT ANSWERS 970 BTU's
Polvolester oils CORRECT ANSWERS have more atmospheric moisture than mineral oil.
The clearance space in a reciprocating compressor CORRECT ANSWERS has an effect on compressor capacity.
Which of the following will cause a major change in compressor capacity when retrofitting to another type of refrigerant? CORRECT ANSWERS Discharge pressure
A disadvantage to the reciprocating compressor over other designs is CORRECT ANSWERS some refrigerant will always remain in the clearance space.
The flow switches of a chiller's control system CORRECT ANSWERS Allow refrigeration
system operation only when the water circulating pumps are energized
What is used to control the flow of water on a water-cooled condenser? CORRECT ANSWERS A water regulating valve
