AIR CONDITIONING CERTIFICATION PRACTICE TEST
What is the movement of heat through space called? - Answers-Radiation
A refrigerant release heat when - Answers-It condenses
Why is it desirable for refrigerant in the suction line to be slightly superheated? -
Answers-To insure liquid refrigerant does not enter the compressor
A 30 pound cylinder of reclaimed R-22 refrigerant has been stored over night at 70
degrees F. What should be the approximate pressure in the cylinder? - Answers-121
psig
14.7 psia( pouds per square inch absolute) is - Answers-Approximately 0 PSIG
When testing the efficiency of a water cooled condenser, the refrigerant condensing
temperature should be no more _____ higher than the leaving water temperature. -
Answers-10 degrees F
What does a temperature differential across a filter-drier indicate? - Answers-Restricted
filter-drier
Which of the following symptoms would be indicative of an oil logged evaporator? -
Answers-Reduce heat transfer through the walls of the coil
When using an electronic leak detecto, the sensor probe - Answers-should be moved at
approximately 1 inch per second
Before a vapor / compression system is opened for service - Answers-the refrigerant
must be recovered using approved equipment
What is the minimum vertical drop from the outlet of the condensate drain pan to the
inlet of the P trap when the evaporator is ahead of the blower? - Answers-3 inches
The temperature rise method of determining air volume CFM is mostly used with a/an; -
Answers-electric resistive heat air handler
What is the main fuction of an air condition condenser? - Answers-To remove heat from
the refrigerant
Refrigerant R-134a vapor enters the condenser at 124 psig, 100 degrees F. It leaves the
condenser at 80 degreesF. What will be the approximate pressure? - Answers-124 psig
(the pressure should not change entering or leaving the condenser)
Which of the following CANNOT be used as a low ambient temperature control? -
Answers-Crankcase regulating valve
, When testing the efficiency of a (10 seer are lower) air cooled condenser, the refrigerant
condensing temperature should be no more than_______ higher than the entering air
temperature - Answers-Approximately 30 degrees F
What is a sling psychrometer used to measure - Answers-wet and dry bulb temperature
A compressor is operating with a discharge pressure of 235.3 psig and a suction
pressure of 35.3 psig. What is the compression ratio (pumping ratio)? - Answers-5:1
(235.3+14.7=250) and (35.3+14.7=50) so 250/5=5
What method does hot gas bypass refer to? - Answers-Capacity control
IF a TEV sensing bulb has lost of its charge, What effect would this have on the air
conditioning system - Answers-It would cause the low side pressure to decrease
An increase in water flow, when using a water cooled condenser, would - Answers-
decrease the operating discharge pressure
The clearance space in reciprocating compressor - Answers-has an effect on
compressor capacity
What is used to control the flow of water on a water-cooled condenser? - Answers-A
water regulating valve
How should metallic vibration eliminators be installed on a system which uses a
reciprocating compressor? - Answers-parallel to the compressor crankshaft
The total amount of heat contained in one pound of a substance calculated from an
accepted temperature base is called - Answers-enthalpy
If non-condensables are trapped in a condenser, what symptoms will be present? -
Answers-Increased heat build-up, high amperage and high discharge pressure.
Many multi-cylinder reciprocating compressor have a capacity control device called; -
Answers-un-loaders
A pilot-operated pressure regulator uses_________ pressure to operate the valve. -
Answers-suction gas
A low-side float metering device is used________. - Answers-on a flooded evaporator
In a direct expansion (DX) evaporator system, refrigerant leaves the evaporator as
______. - Answers-superheated vapor
What is the movement of heat through space called? - Answers-Radiation
A refrigerant release heat when - Answers-It condenses
Why is it desirable for refrigerant in the suction line to be slightly superheated? -
Answers-To insure liquid refrigerant does not enter the compressor
A 30 pound cylinder of reclaimed R-22 refrigerant has been stored over night at 70
degrees F. What should be the approximate pressure in the cylinder? - Answers-121
psig
14.7 psia( pouds per square inch absolute) is - Answers-Approximately 0 PSIG
When testing the efficiency of a water cooled condenser, the refrigerant condensing
temperature should be no more _____ higher than the leaving water temperature. -
Answers-10 degrees F
What does a temperature differential across a filter-drier indicate? - Answers-Restricted
filter-drier
Which of the following symptoms would be indicative of an oil logged evaporator? -
Answers-Reduce heat transfer through the walls of the coil
When using an electronic leak detecto, the sensor probe - Answers-should be moved at
approximately 1 inch per second
Before a vapor / compression system is opened for service - Answers-the refrigerant
must be recovered using approved equipment
What is the minimum vertical drop from the outlet of the condensate drain pan to the
inlet of the P trap when the evaporator is ahead of the blower? - Answers-3 inches
The temperature rise method of determining air volume CFM is mostly used with a/an; -
Answers-electric resistive heat air handler
What is the main fuction of an air condition condenser? - Answers-To remove heat from
the refrigerant
Refrigerant R-134a vapor enters the condenser at 124 psig, 100 degrees F. It leaves the
condenser at 80 degreesF. What will be the approximate pressure? - Answers-124 psig
(the pressure should not change entering or leaving the condenser)
Which of the following CANNOT be used as a low ambient temperature control? -
Answers-Crankcase regulating valve
, When testing the efficiency of a (10 seer are lower) air cooled condenser, the refrigerant
condensing temperature should be no more than_______ higher than the entering air
temperature - Answers-Approximately 30 degrees F
What is a sling psychrometer used to measure - Answers-wet and dry bulb temperature
A compressor is operating with a discharge pressure of 235.3 psig and a suction
pressure of 35.3 psig. What is the compression ratio (pumping ratio)? - Answers-5:1
(235.3+14.7=250) and (35.3+14.7=50) so 250/5=5
What method does hot gas bypass refer to? - Answers-Capacity control
IF a TEV sensing bulb has lost of its charge, What effect would this have on the air
conditioning system - Answers-It would cause the low side pressure to decrease
An increase in water flow, when using a water cooled condenser, would - Answers-
decrease the operating discharge pressure
The clearance space in reciprocating compressor - Answers-has an effect on
compressor capacity
What is used to control the flow of water on a water-cooled condenser? - Answers-A
water regulating valve
How should metallic vibration eliminators be installed on a system which uses a
reciprocating compressor? - Answers-parallel to the compressor crankshaft
The total amount of heat contained in one pound of a substance calculated from an
accepted temperature base is called - Answers-enthalpy
If non-condensables are trapped in a condenser, what symptoms will be present? -
Answers-Increased heat build-up, high amperage and high discharge pressure.
Many multi-cylinder reciprocating compressor have a capacity control device called; -
Answers-un-loaders
A pilot-operated pressure regulator uses_________ pressure to operate the valve. -
Answers-suction gas
A low-side float metering device is used________. - Answers-on a flooded evaporator
In a direct expansion (DX) evaporator system, refrigerant leaves the evaporator as
______. - Answers-superheated vapor
