NATE Exam Air Conditioning and Heat Pumps questions
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with correct answers
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Which |of |the |following |factors |affects |a |customer's |level |of |comfort?
a. |Air |movement
b. |Humidity
c. |Temperature
d. |All |of |the |above |- |correct |answer |d |(All |of |the |above: |air |movement, |humidity, |temperature)
A |cooling |load |calculation |estimates |the |sensible |heat |gain |of |a |structure. |The |maximum |
sensible |capacity |of |a |cooling-only |system |should |be |within |____% |of |this |calculated |value.
a. |±10%
b. |+10%
c. |+15%
d. |+30% |- |correct |answer |c |(+15%)
The |maximum |sensible |cooling |capacity |of |a |heat |pump |should |be |within |____% |of |the |
calculated |sensible |heat |gain |of |a |structure |with |a |large |heating |load.
a. |±10%
b. |+15%
c. |-25%
d. |+25% |- |correct |answer |d |(+25%)
The |combined |output |of |a |heat |pump |and |its |auxiliary |heat |should |not |exceed |the |calculated |
heat |loss |of |a |home |by |more |than |____%.
,a. |10%
b. |15%
c. |20%
d. |25% |- |correct |answer |b |(15%)
What |amount |of |auxiliary |electric |heat |is |needed |when |the |output |of |a |heat |pump |on |a |
design |day |equals |18,800 |Btuh |and |the |heat |loss |of |a |home |is |29,700 |Btuh?
a. |2.1 |kWh
b. |3.2 |kWh
c. |5.0 |kWh
d. |10.9 |kWh
Note: |3,413 |Btu/kW |- |correct |answer |b |(3.2 |kWh)
The |three |processes |that |transfer |heat |energy |are |conduction, |convection, |and |____.
a. |concentration
b. |radiation
c. |refraction
d. |static |pressure |- |correct |answer |b |(radiation)
Heat |transfer |that |occurs |when |substances |of |different |temperatures |are |in |contact |with |each |
other |is |called |____.
a. |concentration
b. |conduction
c. |convection
, d. |radiation |- |correct |answer |b |(conduction)
What |effect |does |raising |the |pressure |in |a |sealed |system |have |on |refrigerant?
a. |It |becomes |more |difficult |to |subcool |the |liquid |refrigerant
b. |It |becomes |more |difficult |to |superheat |the |refrigerant |vapor
c. |The |refrigerant's |boiling |point |decreases
d. |The |refrigerant's |boiling |point |increases |- |correct |answer |d |(The |refrigerant's |boiling |point |
increases)
What |is |the |primary |danger |to |people |near |an |accidental |refrigerant |release |or |spill?
a. |Blurred |vision |caused |by |the |refrigerant |vapor |coming |in |contact |with |the |eyes
b. |Changes |in |weather |patterns |caused |by |global |warming
c. |Damage |to |the |food |chain |caused |by |decreased |ozone |levels |in |the |stratosphere
d. |Suffocation |caused |by |the |heavier |refrigerant |displacing |oxygen |in |the |air |- |correct |answer |d
|(Suffocation |caused |by |the |heavier |refrigerant |displacing |oxygen |in |the |air)
The |maximum |temperature |at |which |refrigerant |may |be |stored |is |____°F |when |the |container |
is |no |more |than |____% |full |of |liquid |by |volume.
a. |120°F, |60%
b. |125°F, |60%
c. |125°F, |80%
d. |135°F, |80% |- |correct |answer |c |(125°F, |80%)
Boiling |of |the |refrigerant |occurs |in |which |system |component?
a. |Compressor
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with correct answers
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Which |of |the |following |factors |affects |a |customer's |level |of |comfort?
a. |Air |movement
b. |Humidity
c. |Temperature
d. |All |of |the |above |- |correct |answer |d |(All |of |the |above: |air |movement, |humidity, |temperature)
A |cooling |load |calculation |estimates |the |sensible |heat |gain |of |a |structure. |The |maximum |
sensible |capacity |of |a |cooling-only |system |should |be |within |____% |of |this |calculated |value.
a. |±10%
b. |+10%
c. |+15%
d. |+30% |- |correct |answer |c |(+15%)
The |maximum |sensible |cooling |capacity |of |a |heat |pump |should |be |within |____% |of |the |
calculated |sensible |heat |gain |of |a |structure |with |a |large |heating |load.
a. |±10%
b. |+15%
c. |-25%
d. |+25% |- |correct |answer |d |(+25%)
The |combined |output |of |a |heat |pump |and |its |auxiliary |heat |should |not |exceed |the |calculated |
heat |loss |of |a |home |by |more |than |____%.
,a. |10%
b. |15%
c. |20%
d. |25% |- |correct |answer |b |(15%)
What |amount |of |auxiliary |electric |heat |is |needed |when |the |output |of |a |heat |pump |on |a |
design |day |equals |18,800 |Btuh |and |the |heat |loss |of |a |home |is |29,700 |Btuh?
a. |2.1 |kWh
b. |3.2 |kWh
c. |5.0 |kWh
d. |10.9 |kWh
Note: |3,413 |Btu/kW |- |correct |answer |b |(3.2 |kWh)
The |three |processes |that |transfer |heat |energy |are |conduction, |convection, |and |____.
a. |concentration
b. |radiation
c. |refraction
d. |static |pressure |- |correct |answer |b |(radiation)
Heat |transfer |that |occurs |when |substances |of |different |temperatures |are |in |contact |with |each |
other |is |called |____.
a. |concentration
b. |conduction
c. |convection
, d. |radiation |- |correct |answer |b |(conduction)
What |effect |does |raising |the |pressure |in |a |sealed |system |have |on |refrigerant?
a. |It |becomes |more |difficult |to |subcool |the |liquid |refrigerant
b. |It |becomes |more |difficult |to |superheat |the |refrigerant |vapor
c. |The |refrigerant's |boiling |point |decreases
d. |The |refrigerant's |boiling |point |increases |- |correct |answer |d |(The |refrigerant's |boiling |point |
increases)
What |is |the |primary |danger |to |people |near |an |accidental |refrigerant |release |or |spill?
a. |Blurred |vision |caused |by |the |refrigerant |vapor |coming |in |contact |with |the |eyes
b. |Changes |in |weather |patterns |caused |by |global |warming
c. |Damage |to |the |food |chain |caused |by |decreased |ozone |levels |in |the |stratosphere
d. |Suffocation |caused |by |the |heavier |refrigerant |displacing |oxygen |in |the |air |- |correct |answer |d
|(Suffocation |caused |by |the |heavier |refrigerant |displacing |oxygen |in |the |air)
The |maximum |temperature |at |which |refrigerant |may |be |stored |is |____°F |when |the |container |
is |no |more |than |____% |full |of |liquid |by |volume.
a. |120°F, |60%
b. |125°F, |60%
c. |125°F, |80%
d. |135°F, |80% |- |correct |answer |c |(125°F, |80%)
Boiling |of |the |refrigerant |occurs |in |which |system |component?
a. |Compressor
