NATE AIR CONDITIONING AND HEAT PUMPS 2024/2025 EXAM QUESTIONS AND DETAILED ANSWERS

NATE AIR CONDITIONING AND HEAT
PUMPS 2024/2025 EXAM QUESTIONS
AND DETAILED ANSWERS

Which of the following factors affects a customer's level of comfort? A. Air

movement, B. Humidity, C. Temperature, D. All of the above - 🧠ANSWER ✔✔D.

All of the above

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% - 🧠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%

Page 1 of 34
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER:
619652435. TERMS OF USE. PRIVACY STATEMENT. ALL RIGHTS RESERVED

,B. + 15%

C. -25%

D. +25% - 🧠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% - 🧠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 - 🧠ANSWER ✔✔b (3.2 kWh)
Page 2 of 34
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER:
619652435. TERMS OF USE. PRIVACY STATEMENT. ALL RIGHTS RESERVED

,The three processes that transfer that occurs when substances of different

temperatures are in contact with each other is called _________.

A. Concentration

B. Conduction

C. Convection

D. Radiation - 🧠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 - 🧠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
Page 3 of 34
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER:
619652435. TERMS OF USE. PRIVACY STATEMENT. ALL RIGHTS RESERVED

, D. Suffocation caused by the heavier refrigerant displacing oxygen in the air -

🧠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% - 🧠ANSWER ✔✔C. 125•F, 80%

Boiling of the refrigerant occurs in which system component?



a. Compressor

b. Condenser

c. Evaporator

d. Metering device - 🧠ANSWER ✔✔c (Evaporator)

Why is superheat necessary in a system that utilizes hermetic compressors?



a. It ensures that dry vapor reaches the compressor so that mechanical damage

does not occur
Page 4 of 34
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER:
619652435. TERMS OF USE. PRIVACY STATEMENT. ALL RIGHTS RESERVED