NATE A/C EXAM #1 QUESTIONS & ANSWERS (RATED A+)

NATE A/C EXAM #1 QUESTIONS &
ANSWERS (RATED A+)

Low airflow over a residential split system air conditioning evaporator can cause

A: Liquid flood-back to the compressor

B: A decrease in compression ratio

C: An increase in suction line superheat

D: Oil logging in the evaporator - ANSWERA: Liquid flood-back to the compressor

All else being normal, if a system shows a high lowside superheat with low condenser
subcooling, what is most likely the problem?

A: Refrigerant overcharge

B: Refrigerant undercharge

C: A partial restriction

D: There is probably no problem - ANSWERB: Refrigerant undercharge

A grille equipped with a damper control is called

A: A vane

B: A register

C: A louver

D: A damper - ANSWERB: A register

As the pressure on a liquid is increased, the vaporization temperature of the liquid

A: Decreases

B: Increases

C: Remains unchanged

, D: Varies - ANSWERB: Increases

An oil separator must be mounted

A: Level

B: Below the compressor crankcase

C: Above the compressor crankcase

D: In the suction line - ANSWERA: Level

Which of the following metering devices controls evaporator pressure?

A: Thermostatic expansion valve

B: Fixed orifice

C: Low side float

D: None of these - ANSWERD: None of these

An automatic expansion valve controls evaporator pressure.

The purpose of the external equalizer on a thermostatic expansion valve is

A: To equalize evaporator pressure drop with respect to the TEV

B: To equalize the evaporator pressure drop

C: To help prevent liquid floodback

D: To allow the high side pressure to equalize to the low side when the compressor
cycles off - ANSWERA: To equalize evaporator pressure drop with respect to the TEV

The higher the MERV rating of a filter-drier, the

A: More efficient the drier at absorbing moisture

B: Less efficient the drier at absorbing moisture

C: Smaller the particles the filter can entrap

D: MERV does not apply to filter-driers - ANSWERD: MERV does not apply to filter-
driers