Arkansas Air Conditioning Electrician
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. An air-conditioning compressor operates at 240 volts and draws 18
amperes under normal operating conditions. Which conductor ampacity
principle is most important when sizing the branch circuit?
A. Size the conductors only according to the compressor's nameplate RLA
B. Size the conductors according to the applicable motor/air-conditioning
equipment rules and the manufacturer's marked minimum circuit ampacity
C. Size the conductors at exactly 125% of the breaker rating
D. Use the service entrance conductor ampacity
Answer: The conductors should be sized according to the applicable motor/air-
conditioning equipment rules and the manufacturer's marked minimum circuit
ampacity.
Rationale: Air-conditioning equipment has specific NEC requirements, and the
equipment nameplate commonly provides minimum circuit ampacity (MCA) and
maximum overcurrent protective device information. The MCA is not simply the
compressor running current multiplied by an arbitrary percentage.
2. A condenser nameplate specifies a maximum overcurrent protective device
of 40 amperes. Which breaker selection is generally appropriate if the
calculated circuit requirements permit it?
,A. 20 A
B. 25 A
C. 40 A
D. 60 A
Answer: 40 A
Rationale: The maximum overcurrent protective device marked on the
equipment nameplate establishes the upper permitted protective-device rating
under the applicable equipment rules. The actual installation must also comply
with the equipment's minimum circuit ampacity and applicable NEC
requirements.
3. What is the primary purpose of a disconnecting means located within sight
of HVAC equipment?
A. To increase compressor starting torque
B. To provide a convenient means of isolating the equipment from its supply
C. To reduce the equipment's operating voltage
D. To eliminate the need for grounding
Answer: To provide a convenient means of isolating the equipment from its
supply.
Rationale: A disconnecting means allows servicing personnel to isolate the
equipment from the electrical supply. Disconnect requirements for HVAC
equipment are governed by the applicable NEC provisions and equipment
location requirements.
4. A 240-volt single-phase condenser has two ungrounded conductors and an
equipment grounding conductor. Which conductor normally carries current
during balanced operation?
A. Only the grounding conductor
B. Only one ungrounded conductor
C. Both ungrounded conductors
D. The grounding conductor and one ungrounded conductor
,Answer: Both ungrounded conductors
Rationale: In a 240-volt single-phase circuit, both ungrounded conductors supply
the load. The equipment grounding conductor normally carries current only
during a fault condition.
5. A 24-volt HVAC control transformer has a 240-volt primary. What is the
principal function of the transformer?
A. Increase 24 volts to 240 volts
B. Convert AC to DC
C. Reduce the supply voltage to a lower control voltage
D. Increase compressor horsepower
Answer: Reduce the supply voltage to a lower control voltage.
Rationale: HVAC control transformers commonly step line voltage down to
approximately 24 volts for thermostats, contactor coils, relays, and other control
components.
6. A 24-volt transformer has a 40 VA rating. Approximately how much current
can its secondary supply continuously at full VA capacity?
A. 0.6 A
B. 1.67 A
C. 4.0 A
D. 16.7 A
Answer: Approximately 1.67 A
Rationale: Transformer current can be calculated using I = VA ÷ V. Therefore, 40
VA ÷ 24 V ≈ 1.67 A.
7. What is the primary function of a contactor in a typical air-conditioning
condenser?
A. Sense refrigerant pressure
B. Switch the high-current compressor and condenser-fan circuit using a control
, signal
C. Convert AC voltage to DC
D. Measure compressor insulation resistance
Answer: Switch the high-current compressor and condenser-fan circuit using a
control signal.
Rationale: The contactor allows a relatively small 24-volt control circuit to
operate line-voltage equipment loads such as compressors and condenser fans.
8. A contactor coil is rated for 24 VAC but measures 0 volts across its
terminals when the thermostat calls for cooling. What should be checked
first?
A. Compressor oil level
B. Refrigerant charge
C. The 24-volt control circuit and its source
D. Condenser coil cleanliness
Answer: The 24-volt control circuit and its source
Rationale: A zero-voltage measurement across the coil during a valid cooling
call indicates that control voltage may not be reaching the coil. The technician
should trace the control circuit systematically, including the transformer, fuse,
thermostat, safety controls, and wiring.
9. What happens to current in a series circuit if one normally closed safety
control opens?
A. Current increases through the entire circuit
B. Current continues unchanged
C. Current is interrupted through that series path
D. Voltage automatically doubles
Answer: Current is interrupted through that series path.
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A Instant Download Pdf
1. An air-conditioning compressor operates at 240 volts and draws 18
amperes under normal operating conditions. Which conductor ampacity
principle is most important when sizing the branch circuit?
A. Size the conductors only according to the compressor's nameplate RLA
B. Size the conductors according to the applicable motor/air-conditioning
equipment rules and the manufacturer's marked minimum circuit ampacity
C. Size the conductors at exactly 125% of the breaker rating
D. Use the service entrance conductor ampacity
Answer: The conductors should be sized according to the applicable motor/air-
conditioning equipment rules and the manufacturer's marked minimum circuit
ampacity.
Rationale: Air-conditioning equipment has specific NEC requirements, and the
equipment nameplate commonly provides minimum circuit ampacity (MCA) and
maximum overcurrent protective device information. The MCA is not simply the
compressor running current multiplied by an arbitrary percentage.
2. A condenser nameplate specifies a maximum overcurrent protective device
of 40 amperes. Which breaker selection is generally appropriate if the
calculated circuit requirements permit it?
,A. 20 A
B. 25 A
C. 40 A
D. 60 A
Answer: 40 A
Rationale: The maximum overcurrent protective device marked on the
equipment nameplate establishes the upper permitted protective-device rating
under the applicable equipment rules. The actual installation must also comply
with the equipment's minimum circuit ampacity and applicable NEC
requirements.
3. What is the primary purpose of a disconnecting means located within sight
of HVAC equipment?
A. To increase compressor starting torque
B. To provide a convenient means of isolating the equipment from its supply
C. To reduce the equipment's operating voltage
D. To eliminate the need for grounding
Answer: To provide a convenient means of isolating the equipment from its
supply.
Rationale: A disconnecting means allows servicing personnel to isolate the
equipment from the electrical supply. Disconnect requirements for HVAC
equipment are governed by the applicable NEC provisions and equipment
location requirements.
4. A 240-volt single-phase condenser has two ungrounded conductors and an
equipment grounding conductor. Which conductor normally carries current
during balanced operation?
A. Only the grounding conductor
B. Only one ungrounded conductor
C. Both ungrounded conductors
D. The grounding conductor and one ungrounded conductor
,Answer: Both ungrounded conductors
Rationale: In a 240-volt single-phase circuit, both ungrounded conductors supply
the load. The equipment grounding conductor normally carries current only
during a fault condition.
5. A 24-volt HVAC control transformer has a 240-volt primary. What is the
principal function of the transformer?
A. Increase 24 volts to 240 volts
B. Convert AC to DC
C. Reduce the supply voltage to a lower control voltage
D. Increase compressor horsepower
Answer: Reduce the supply voltage to a lower control voltage.
Rationale: HVAC control transformers commonly step line voltage down to
approximately 24 volts for thermostats, contactor coils, relays, and other control
components.
6. A 24-volt transformer has a 40 VA rating. Approximately how much current
can its secondary supply continuously at full VA capacity?
A. 0.6 A
B. 1.67 A
C. 4.0 A
D. 16.7 A
Answer: Approximately 1.67 A
Rationale: Transformer current can be calculated using I = VA ÷ V. Therefore, 40
VA ÷ 24 V ≈ 1.67 A.
7. What is the primary function of a contactor in a typical air-conditioning
condenser?
A. Sense refrigerant pressure
B. Switch the high-current compressor and condenser-fan circuit using a control
, signal
C. Convert AC voltage to DC
D. Measure compressor insulation resistance
Answer: Switch the high-current compressor and condenser-fan circuit using a
control signal.
Rationale: The contactor allows a relatively small 24-volt control circuit to
operate line-voltage equipment loads such as compressors and condenser fans.
8. A contactor coil is rated for 24 VAC but measures 0 volts across its
terminals when the thermostat calls for cooling. What should be checked
first?
A. Compressor oil level
B. Refrigerant charge
C. The 24-volt control circuit and its source
D. Condenser coil cleanliness
Answer: The 24-volt control circuit and its source
Rationale: A zero-voltage measurement across the coil during a valid cooling
call indicates that control voltage may not be reaching the coil. The technician
should trace the control circuit systematically, including the transformer, fuse,
thermostat, safety controls, and wiring.
9. What happens to current in a series circuit if one normally closed safety
control opens?
A. Current increases through the entire circuit
B. Current continues unchanged
C. Current is interrupted through that series path
D. Voltage automatically doubles
Answer: Current is interrupted through that series path.
