HVAC EXCELLENCE EXAM QUESTIONS AND ANSWERS LATEST VERSION () (2025)

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• hvac excellence exam questions and answers latest

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HVAC EXCELLENCE EXAM QUESTIONS AND ANSWERS LATEST VERSION (2024-2025)

Heat which causes a change in temperature of a substance is called - Answers sensible heat,

Heat added to a substance without a rise in temperature; (example: liquid refrigerant to gas) this
process la called? - Answers latent heat

Heat added to the refrigerant in vapor state after the evaporation process is called, - Answers superheat

A scroll compressor moves refrigerant by means of; - Answers involute spirals

The movement of heat by way of fluid or is called; air - Answers convection

The movement of heat through a solid object is called; - Answers radiation

The standard unit for measuring the quantity of heat in a substance is - Answers British Thermal Unit

A refrigerant gives up heat when it; - Answers it condenses

Why must refrigerant in the suction line be slightly warmer than the saturation temperature? - Answers
prevent liquid slugging of the compressor.

It is desirable for refrigerant in the suction line to be slightly superheated in order to; - Answers insure
liquid refrigerant does not enter the compressor.,

The state of the refrigerant in the suction line should be - Answers low pressure/ low temperature vapor

The state of the refrigerant entering the condenser is - Answers High Pressure/ Highly Superheated
Vapor

The Evaporator - Answers Transfers heat from the refrigerated space to the refrigerant

The Evaporator - Answers Transfers heat from the refrigerated space to the refrigerant

Which of the following is not a Thermodynamic Property of refrigerant - Answers Flammability

The sequential order of steps in the vapor-compression process are: - Answers 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 - Answers 201 Degrees Faranheit

Fan Airflow pressures are usually measured in - Answers Inches of water column

Zero Psia (pounds per square inch absolute) is - Answers a pressure which cannot be further reduced

Zero Psig (pounds per square inch gauge) - Answers The same as atmospheric pressure

, The Temperature at which moisture will start to condense from the air is called - Answers Dew Point
Temperature

A Compound pressure gauge measures - Answers Pressure and Vacuum

A Mechanical shaft seal is necesssary on a - Answers Open drive compressor

Liquid slugging is - Answers Liquid refrigerant in the compressor clearance space

The Clearance space in a reciprocating compressor - Answers has an effect on compressor capacity

Which of the following types of air conditioning compressors is more efficient - Answers Centrifugal

Which of the following represnet the right order for the functionsof a condenser - Answers De-
Superheats, Condenses, and Sub-cools

Refrigerant R-134a vapor enters the condenser at 124psig, 100 degrees faranheit, It leaves as a liquid
from the condenser, sub-cooled 20 degrees faranheit, and the pressure will be approximately - Answers
124 psig

There are 3 basic types of condensers, air cooled, water cooled, and - Answers evaporative cooled

10 lbs of refrigerant passing through a water cooled condenser will lose 20 BTU of heat/ pound. If 10#'s
of water passes through the condenser with an entering temp of 80 degrees, the temp of the water
leaving the condenser is - Answers 100 degrees faranheit

The heat removed from the refrigerant by the condenser is - Answers both sensible and latent heat

An energy recovery ventilator is - Answers an air to air heat exhanger to recover heat

Which of hte following can not be used as a low ambient temperature control? - Answers Crankcase
regulating valves

When testing the efficiency of an air cooled condenser, the refrigerant condensing temperature should
be no more than _____ higher than the entering air temp. - Answers 30 degrees

The First function a condenser must perform is to ___ the refrigerant before condesing can occur. -
Answers De-Superheat

A thermostatic expansion valve is designed to maintain - Answers Constant evaporator superheat

The thermostatic expansion valve has three operating pressures - Answers Evaporator, Spring and
Sensing bulb Pressure

When Mounting a thermostatic expansion valve sensor bulb, which of the folling is NOT true? - Answers
It must be installed lower than the valve body