HVAC EXCELLENCE EXAMS 2025 – HVAC
EXCELLENCE ELECTRICITY EXAM 2025 AND HVAC
AC EXAM 2025 EACH CONTAIN 100 PREP
QUESTIONS AND CORRECT ANSWERS (BRAND
NEW!)
Heat which causes a change in temperature of a
substance is called - ...ANSWER...✓✓sensible heat,
Heat added to a substance without a rise in temperature;
(example: liquid refrigerant to gas) this process la called?
- ...ANSWER...✓✓latent heat
Heat added to the refrigerant in vapor state after the
evaporation process is called, - ...ANSWER...✓✓superheat
A scroll compressor moves refrigerant by means of; -
...ANSWER...✓✓involute spirals
The movement of heat by way of fluid or is called; air -
...ANSWER...✓✓convection
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The movement of heat through a solid object is called; -
...ANSWER...✓✓radiation
The standard unit for measuring the quantity of heat in a
substance is - ...ANSWER...✓✓British Thermal Unit
A refrigerant gives up heat when it; - ...ANSWER...✓✓it
condenses
Why must refrigerant in the suction line be slightly
warmer than the saturation temperature? -
...ANSWER...✓✓prevent liquid slugging of the compressor.
It is desirable for refrigerant in the suction line to be
slightly superheated in order to; - ...ANSWER...✓✓insure
liquid refrigerant does not enter the compressor.,
The state of the refrigerant in the suction line should be -
...ANSWER...✓✓low pressure/ low temperature vapor
The state of the refrigerant entering the condenser is -
...ANSWER...✓✓High Pressure/ Highly Superheated Vapor
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The Evaporator - ...ANSWER...✓✓Transfers heat from the
refrigerated space to the refrigerant
The Evaporator - ...ANSWER...✓✓Transfers heat from the
refrigerated space to the refrigerant
Which of the following is not a Thermodynamic Property
of refrigerant - ...ANSWER...✓✓Flammability
The sequential order of steps in the vapor-compression
process are: - ...ANSWER...✓✓Compression,
Condensation, Expansion, Vaporization
If a 30 lb container of $-410A refrigerant has been stored
over night at 70 degrees F, the pressure in the cylinder
should be approximately - ...ANSWER...✓✓201 Degrees
Faranheit
Fan Airflow pressures are usually measured in -
...ANSWER...✓✓Inches of water column
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Zero Psia (pounds per square inch absolute) is -
...ANSWER...✓✓a pressure which cannot be further
reduced
Zero Psig (pounds per square inch gauge) -
...ANSWER...✓✓The same as atmospheric pressure
The Temperature at which moisture will start to condense
from the air is called - ...ANSWER...✓✓Dew Point
Temperature
A Compound pressure gauge measures -
...ANSWER...✓✓Pressure and Vacuum
A Mechanical shaft seal is necesssary on a -
...ANSWER...✓✓Open drive compressor
Liquid slugging is - ...ANSWER...✓✓Liquid refrigerant in
the compressor clearance space
The Clearance space in a reciprocating compressor -
...ANSWER...✓✓has an effect on compressor capacity