NATE Exam: Air Conditioning and Heat
Pumps
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%
,NATE Exam: Air Conditioning and Heat
Pumps
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)
, NATE Exam: Air Conditioning and Heat
Pumps
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
b. Condenser
Pumps
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%
,NATE Exam: Air Conditioning and Heat
Pumps
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)
, NATE Exam: Air Conditioning and Heat
Pumps
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
b. Condenser
