Refrigeration Test questions and
answers
Automatic expansion valves work with - correct answer ✔✔ Evaporator pressure closes valve
spring pressure opens valve
A faulty check in a pump will cause the most damage on - correct answer ✔✔ Startup
If the T E V's sensing bulb falls off the suction line you will - correct answer ✔✔ Flood the
evaporator
A clogged condenser pump strainer can cause a loss of pressure causing - correct answer ✔✔
High condenser head pressure
A solenoid valve is part of the pump down cycle - correct answer ✔✔ Thermostat solenoid valve
and then the low pressure control
What is proper start up procedure? - correct answer ✔✔ Start chiller water pump, start
condenser water pump,check tower fans, check compressor oil, check position of refrigeration
valves, start machine.
A reciprocating machine cycles multistage compressors on and off with the - correct answer ✔✔
Low pressure control
The refrigerant that has the best refrigerant effect is - correct answer ✔✔ Ammonia
,In an induced draft cooling tower that is operating efficiently the leaving water temp is at -
correct answer ✔✔ Some temp between the prevailing dry and wet bulb temp
A sudden reduction in the supply of condenser water could result in - correct answer ✔✔ An
open valve
Reciprocating compressor unloaders work by - correct answer ✔✔ Keeping compression suction
valve open
In a well designed system the percent of lubricant circulated should not exceed - correct answer
✔✔ 10%
Oil foaming in the compressor is a result of - correct answer ✔✔ Liquid refrigerant in the
crankcase
The main reason for installing a oil separator on the discharge line is to - correct answer ✔✔
Return oil back to the compressor crankcase
In a reciprocating compressor using the splash system for lubrication the domain of oil is caused
by a - correct answer ✔✔ Sudden decrease in pressure
Charge vapor into the - correct answer ✔✔ Suction side of the compressor (low side)
Oil in a refrigerant system reduces - correct answer ✔✔ Wear and friction
A filter drier is used to - correct answer ✔✔ Remove moister
Oil separator is located on the discharge line as - correct answer ✔✔ Far from the compressor
as possible
, A solenoid valve - correct answer ✔✔ Does not vary the flow of refrigerant
The T E V - correct answer ✔✔ Modulates and controls the flow of refrigerant into the
evaporator
If you use an automatic expansion valve with a variable load you will - correct answer ✔✔
Starve the evaporator
A motor has 4 belts if one is worn replace - correct answer ✔✔ All the belts
Non condensable gases can cause - correct answer ✔✔ High head pressure
Horse power will - correct answer ✔✔ Increase as the head pressure increases
Horse power will - correct answer ✔✔ Decrease as the head pressure decreases
Superheated vapor is defined as a - correct answer ✔✔ Dry vapor
A sling psychrometer is used to measure - correct answer ✔✔ Relative humidity
An automatic expansion valve maintains a - correct answer ✔✔ Constant evaporator pressure
If the evaporator doesn't respond to adjustments of the T E V it may be due - correct answer
✔✔ To oil logged on the low side
answers
Automatic expansion valves work with - correct answer ✔✔ Evaporator pressure closes valve
spring pressure opens valve
A faulty check in a pump will cause the most damage on - correct answer ✔✔ Startup
If the T E V's sensing bulb falls off the suction line you will - correct answer ✔✔ Flood the
evaporator
A clogged condenser pump strainer can cause a loss of pressure causing - correct answer ✔✔
High condenser head pressure
A solenoid valve is part of the pump down cycle - correct answer ✔✔ Thermostat solenoid valve
and then the low pressure control
What is proper start up procedure? - correct answer ✔✔ Start chiller water pump, start
condenser water pump,check tower fans, check compressor oil, check position of refrigeration
valves, start machine.
A reciprocating machine cycles multistage compressors on and off with the - correct answer ✔✔
Low pressure control
The refrigerant that has the best refrigerant effect is - correct answer ✔✔ Ammonia
,In an induced draft cooling tower that is operating efficiently the leaving water temp is at -
correct answer ✔✔ Some temp between the prevailing dry and wet bulb temp
A sudden reduction in the supply of condenser water could result in - correct answer ✔✔ An
open valve
Reciprocating compressor unloaders work by - correct answer ✔✔ Keeping compression suction
valve open
In a well designed system the percent of lubricant circulated should not exceed - correct answer
✔✔ 10%
Oil foaming in the compressor is a result of - correct answer ✔✔ Liquid refrigerant in the
crankcase
The main reason for installing a oil separator on the discharge line is to - correct answer ✔✔
Return oil back to the compressor crankcase
In a reciprocating compressor using the splash system for lubrication the domain of oil is caused
by a - correct answer ✔✔ Sudden decrease in pressure
Charge vapor into the - correct answer ✔✔ Suction side of the compressor (low side)
Oil in a refrigerant system reduces - correct answer ✔✔ Wear and friction
A filter drier is used to - correct answer ✔✔ Remove moister
Oil separator is located on the discharge line as - correct answer ✔✔ Far from the compressor
as possible
, A solenoid valve - correct answer ✔✔ Does not vary the flow of refrigerant
The T E V - correct answer ✔✔ Modulates and controls the flow of refrigerant into the
evaporator
If you use an automatic expansion valve with a variable load you will - correct answer ✔✔
Starve the evaporator
A motor has 4 belts if one is worn replace - correct answer ✔✔ All the belts
Non condensable gases can cause - correct answer ✔✔ High head pressure
Horse power will - correct answer ✔✔ Increase as the head pressure increases
Horse power will - correct answer ✔✔ Decrease as the head pressure decreases
Superheated vapor is defined as a - correct answer ✔✔ Dry vapor
A sling psychrometer is used to measure - correct answer ✔✔ Relative humidity
An automatic expansion valve maintains a - correct answer ✔✔ Constant evaporator pressure
If the evaporator doesn't respond to adjustments of the T E V it may be due - correct answer
✔✔ To oil logged on the low side
