Refrigeration Test Exam Questions with
Complete Solutions
Automatic expansion valves work with - Answer-Evaporator pressure closes valve
spring pressure opens valve
A faulty check in a pump will cause the most damage on - Answer-Startup
If the T E V's sensing bulb falls off the suction line you will - Answer-Flood the
evaporator
A clogged condenser pump strainer can cause a loss of pressure causing - Answer-
High condenser head pressure
A solenoid valve is part of the pump down cycle - Answer-Thermostat solenoid valve
and then the low pressure control
What is proper start up procedure? - 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 - Answer-
Low pressure control
The refrigerant that has the best refrigerant effect is - Answer-Ammonia
In an induced draft cooling tower that is operating efficiently the leaving water temp is at
- Answer-Some temp between the prevailing dry and wet bulb temp
A sudden reduction in the supply of condenser water could result in - Answer-An open
valve
Reciprocating compressor unloaders work by - Answer-Keeping compression suction
valve open
In a well designed system the percent of lubricant circulated should not exceed -
Answer-10%
Oil foaming in the compressor is a result of - Answer-Liquid refrigerant in the crankcase
The main reason for installing a oil separator on the discharge line is to - 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 - Answer-Sudden decrease in pressure
Charge vapor into the - Answer-Suction side of the compressor (low side)
Oil in a refrigerant system reduces - Answer-Wear and friction
A filter drier is used to - Answer-Remove moister
Oil separator is located on the discharge line as - Answer-Far from the compressor as
possible
A solenoid valve - Answer-Does not vary the flow of refrigerant
The T E V - Answer-Modulates and controls the flow of refrigerant into the evaporator
If you use an automatic expansion valve with a variable load you will - Answer-Starve
the evaporator
A motor has 4 belts if one is worn replace - Answer-All the belts
Non condensable gases can cause - Answer-High head pressure
Horse power will - Answer-Increase as the head pressure increases
Horse power will - Answer-Decrease as the head pressure decreases
Superheated vapor is defined as a - Answer-Dry vapor
A sling psychrometer is used to measure - Answer-Relative humidity
An automatic expansion valve maintains a - Answer-Constant evaporator pressure
If the evaporator doesn't respond to adjustments of the T E V it may be due - Answer-To
oil logged on the low side
When using a bribe solution in a system us - Answer-Di-chromate tablets to prevent
rusting
If a halide torch turns yellow it is caused by - Answer-A clogged sample tube
The pressure of having 2 compressors in a cascade system is to operate at - Answer-
Very low temperatures
A pressure relief valve is better than a fusible plug because a - Answer-Fusible plug can
not reseat
Complete Solutions
Automatic expansion valves work with - Answer-Evaporator pressure closes valve
spring pressure opens valve
A faulty check in a pump will cause the most damage on - Answer-Startup
If the T E V's sensing bulb falls off the suction line you will - Answer-Flood the
evaporator
A clogged condenser pump strainer can cause a loss of pressure causing - Answer-
High condenser head pressure
A solenoid valve is part of the pump down cycle - Answer-Thermostat solenoid valve
and then the low pressure control
What is proper start up procedure? - 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 - Answer-
Low pressure control
The refrigerant that has the best refrigerant effect is - Answer-Ammonia
In an induced draft cooling tower that is operating efficiently the leaving water temp is at
- Answer-Some temp between the prevailing dry and wet bulb temp
A sudden reduction in the supply of condenser water could result in - Answer-An open
valve
Reciprocating compressor unloaders work by - Answer-Keeping compression suction
valve open
In a well designed system the percent of lubricant circulated should not exceed -
Answer-10%
Oil foaming in the compressor is a result of - Answer-Liquid refrigerant in the crankcase
The main reason for installing a oil separator on the discharge line is to - 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 - Answer-Sudden decrease in pressure
Charge vapor into the - Answer-Suction side of the compressor (low side)
Oil in a refrigerant system reduces - Answer-Wear and friction
A filter drier is used to - Answer-Remove moister
Oil separator is located on the discharge line as - Answer-Far from the compressor as
possible
A solenoid valve - Answer-Does not vary the flow of refrigerant
The T E V - Answer-Modulates and controls the flow of refrigerant into the evaporator
If you use an automatic expansion valve with a variable load you will - Answer-Starve
the evaporator
A motor has 4 belts if one is worn replace - Answer-All the belts
Non condensable gases can cause - Answer-High head pressure
Horse power will - Answer-Increase as the head pressure increases
Horse power will - Answer-Decrease as the head pressure decreases
Superheated vapor is defined as a - Answer-Dry vapor
A sling psychrometer is used to measure - Answer-Relative humidity
An automatic expansion valve maintains a - Answer-Constant evaporator pressure
If the evaporator doesn't respond to adjustments of the T E V it may be due - Answer-To
oil logged on the low side
When using a bribe solution in a system us - Answer-Di-chromate tablets to prevent
rusting
If a halide torch turns yellow it is caused by - Answer-A clogged sample tube
The pressure of having 2 compressors in a cascade system is to operate at - Answer-
Very low temperatures
A pressure relief valve is better than a fusible plug because a - Answer-Fusible plug can
not reseat
