Unit 3
The state of the refrigerant at the outlet of the condenser should be...
100% subcooled liquid
The state of the refrigerant at the outlet of the evaporator should be...
100% superheated vapor
A properly operating compressor should have ___ at its inlet and ___ at its outlet.
100% vapor at the inlet, 100% vapor at the outlet
If the evaporator outlet temperature on an R-410A system is 50 degrees Fahrenheit and the evaporator superheat is 10 degrees Fahrenheit, what is the evaporating pressure of the refrigerant in this system?
118 psig
The condensing pressure is 417.4 psig for R-410A and the condenser outlet temperature is 108 degrees Fahrenheit. How much subcooling is there in the condenser?
12 degrees Fahrenheit
One ton of refrigeration is the equivalent of moving heat at a rate of...
12,000 BTU/hr
The evaporating pressure for R-22 is 76 psig and the evaporator outlet temperature is 58 degrees Fahrenheit. What is the evaporator superheat?
13 degrees Fahrenheit
When an air-conditioning system operates in a vacuum, which of the following is true?
Air will be pulled into the system
Of the following refrigerants, which has the lowest global warming potential (GWP)? A. R-410A B. R-134A C. R-407C D. R-1234yf
D.
The color coding for an R-22 refrigerant cylinder is...
Green
One of the challenges on plotting an R-407C system on a pressure/enthalpy chart is that this refrigerant...
Has a high temperature glide
A refrigeration system that is intended to provide comfort cooling would be classified as what type of system?
High-Temperature
A refrigeration system that maintains a space at a temperature between 35 degrees Fahrenheit and 40 degrees Fahrenheit would be classified as what type of system?
Medium-Temperature
The expansion device is responsible for...
Metering the flow of refrigerant into the system
The term that is used to quantify the amount of heat absorbed in the evaporator is...
Net refrigeration effect
The color-coding for an R-404A refrigerant cylinder...
Orange
The three processes commonly used to describe refrigerant handling are...
Recovering, recycling, reclaiming
The basic refrigeration system can be best described as...
Repeating, vapor compression cycle
The thumbprint-shaped region on the pressure/enthalpy chart is called...
Saturation curve
Of the following compressors, which is a residential compressor that is forgiving when it comes to having liquid enter it?
Scroll compressor
The three regions on a pressure/enthalpy chart are...
Superheated vapor, subcooled liquid, saturated.
If the evaporating pressure was 76 psig for R-22 and the compressor inlet temperature was 65 degrees Fahrenheit, what would be the total superheat entering the compressor?
20 degrees Fahrenheit
Saturated R-410A at a pressure of 95 psig will change at a temperature of
29 degrees Fahrenheit
The state of the refrigerant at the inlet of the evaporator is approximately...
75% liquid, 25% vapor
Which of the following statements is true with regards to reciprocating and rotary compressors? A. Rotary and reciprocating compressors with similar capacities are similarly sized. B. Both rotary and reciprocating compressors are equipped with suction and discharge valves. C. Both rotary and reciprocating compressors can be opened for service. D. For compressors with similar capacities, rotary compressors are smaller than reciprocating compressors.
D.
