1020 Final Flashcards
To read system pressure the service valves are placed in the ________ position.
Back seated
Example sentence: Make sure the service valves are back seated before checking the system pressure.
The ________ rejects heat in the refrigeration cycle.
Condenser
Example sentence: The condenser is responsible for rejecting heat in the refrigeration cycle.
The _______ absorbs heat in the refrigeration cycle.
Evaporator
Example sentence: The evaporator absorbs heat in the refrigeration cycle.
The condenser performs three functions when operating properly. Name these functions in the order in which they occur.
Desuperheating
Condense
Subcooling
Example sentence: The condenser first desuperheats, then condenses, and finally subcools the refrigerant.
The purpose of the TEV is to maintain a nearly constant _________ with varying loads on the evaporator.
Superheat
Example sentence: The TEV helps maintain a nearly constant superheat in the evaporator with changing loads.
The TEV sensing bulb is connected to the ________ of the evaporator coil.
Outlet
Example sentence: The TEV sensing bulb is connected to the outlet of the evaporator coil for accurate temperature control.
An increase in superheat causes the pressure on top of the TEV’s diaphragm to:
Increase
Example sentence: When superheat increases, the pressure on top of the TEV’s diaphragm also increases.
Which type of system is considered a critical charge?
Cap tube
Example sentence: A cap tube system is considered a critical charge system.
A pump down procedure is started when the ________ valve is front seated.
Liquid line
Example sentence: The pump down procedure begins when the liquid line valve is front seated.
The receiver is located in the:
Liquid line
Example sentence: The receiver is typically located in the liquid line of a refrigeration system.
To accurately measure a deep vacuum you would use:
Vacuum gauge
Example sentence: Use a vacuum gauge to accurately measure a deep vacuum in the system.
Vapor refrigerant is added to an operating system thru the:
Suction line
Example sentence: Vapor refrigerant is added to the system through the suction line.
The most accurate method of charging a self-contained system (refrigerator, window unit) is?
Weigh-in
Example sentence: The most accurate method for charging a self-contained system is by weighing in the refrigerant.
The term evacuation refers to?
Using a vacuum pump
Example sentence: Evacuation in refrigeration refers to using a vacuum pump to remove air and moisture from the system.
A fan cycle control on the condenser motor is used to:
Raise head pressure in cold weather
Example sentence: The fan cycle control on the condenser motor is used to increase head pressure during cold weather conditions.
A refrigerator system holds 8 pounds and 12 ounces of refrigerant cylinder weighs 34 pounds and 5 ounces. How much should the cylinder weigh after the system is properly charged?
25 pounds and 9 ounces
Example sentence: After properly charging the system, the cylinder should weigh 25 pounds and 9 ounces.
A R134A system is operating with a low side pressure of 24 psig and a high side pressure of 140 psig. The suction line temperature in 35F and liquid line temperature of 95F. What is the superheat?
9F
Example sentence: With the given pressures and temperatures, the superheat is calculated to be 9F.
When liquid charging the refrigeration system should be ________ and liquid refrigerant should be charged in to the ___________.
ON;suction line
What would happen to the high pressure if the condenser fan motor will not operate?
Increase
Example sentence: If the condenser fan motor fails to operate, the high pressure in the system will increase.
What would happen to compressor amperage draw with an increase in load pressure?
Increase
Example sentence: As the load pressure increases, the compressor’s amperage draw will also increase.
What happens to the superheat with a dirty evaporator?
Increase
Example sentence: A dirty evaporator will cause an increase in superheat in the system.
There are two places in a system that divide the low and high side. One is the valves in the compressor and the second one is the ___________
Expansion device
Example sentence: The expansion device is one of the components that divide the low and high side in a refrigeration system.
