NATE A/C EXAM #1 QUESTIONS AND ANSWERS
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 - Answers- A: Liquid flood-back to the compressor
Which of the following is the correct sequence of work?
A: Attach gauge manifold, recover refrigerant, replace filter core, evacuate the system,
recharge the system.
B: Recover refrigerant, evacuate the system, replace filter core, recharge the system.
C: Attach gauge manifold, evacuate the system, replace filter core, recover refrigerant,
recharge the system.
D: Attach gauge manifold, recharge the system, evacuate the system, replace filter
core. - Answers- A: Attach gauge manifold, recover refrigerant, replace filter core,
evacuate the system, recharge the system.
As the pressure on a liquid is increased, the vaporization temperature of the liquid
A: Decreases
B: Increases
C: Remains unchanged
D: Varies - Answers- B: Increases
An oil separator must be mounted
A: Level
B: Below the compressor crankcase
C: Above the compressor crankcase
D: In the suction line - Answers- A: Level
, 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 - Answers- D: MERV does not apply to filter-
driers
Minimum Efficiency Reporting Value - MERV ratings are used to rate the ability of an air
conditioning filter to remove dust from the air as it passes through the filter. MERV is a
standard used to measure the overall efficiency of a filter. Higher MERV ratings mean
fewer dust particles and other airborne contaminants pass through the filter. Filters with
a merv rating of 9 to 12 are used in commercial and industrial applications and will stop
particles in the 1 to 3 micron range. These filters are a great choice for home owners
who want the best dust control possible. When using filters with Merv 9 ratings and
above it is important to clean or replace them when recommended by the manufacturer
because they will have a negative effect on air flow when they become dirty. This can
lead to performance problems and decreased operating efficiency. The most efficient
filters have merv ratings of 13 to 16 and will stop particles as small as .3 microns. These
filters are used in hospitals and other super clean environments.
Zeolite is used with
A: Refrigerant filter-driers
B: HEPA filters
C: Pipe threads
D: Solder - Answers- A: Refrigerant filter-driers
Vacuum pressures are measured in
A: Microns
B: Millimeters of mercury
C: Inches of mercury
D: All of the above - Answers- D: All of the above
The number 25,400 relates to
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 - Answers- A: Liquid flood-back to the compressor
Which of the following is the correct sequence of work?
A: Attach gauge manifold, recover refrigerant, replace filter core, evacuate the system,
recharge the system.
B: Recover refrigerant, evacuate the system, replace filter core, recharge the system.
C: Attach gauge manifold, evacuate the system, replace filter core, recover refrigerant,
recharge the system.
D: Attach gauge manifold, recharge the system, evacuate the system, replace filter
core. - Answers- A: Attach gauge manifold, recover refrigerant, replace filter core,
evacuate the system, recharge the system.
As the pressure on a liquid is increased, the vaporization temperature of the liquid
A: Decreases
B: Increases
C: Remains unchanged
D: Varies - Answers- B: Increases
An oil separator must be mounted
A: Level
B: Below the compressor crankcase
C: Above the compressor crankcase
D: In the suction line - Answers- A: Level
, 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 - Answers- D: MERV does not apply to filter-
driers
Minimum Efficiency Reporting Value - MERV ratings are used to rate the ability of an air
conditioning filter to remove dust from the air as it passes through the filter. MERV is a
standard used to measure the overall efficiency of a filter. Higher MERV ratings mean
fewer dust particles and other airborne contaminants pass through the filter. Filters with
a merv rating of 9 to 12 are used in commercial and industrial applications and will stop
particles in the 1 to 3 micron range. These filters are a great choice for home owners
who want the best dust control possible. When using filters with Merv 9 ratings and
above it is important to clean or replace them when recommended by the manufacturer
because they will have a negative effect on air flow when they become dirty. This can
lead to performance problems and decreased operating efficiency. The most efficient
filters have merv ratings of 13 to 16 and will stop particles as small as .3 microns. These
filters are used in hospitals and other super clean environments.
Zeolite is used with
A: Refrigerant filter-driers
B: HEPA filters
C: Pipe threads
D: Solder - Answers- A: Refrigerant filter-driers
Vacuum pressures are measured in
A: Microns
B: Millimeters of mercury
C: Inches of mercury
D: All of the above - Answers- D: All of the above
The number 25,400 relates to
