NEW MEXICO JOURNEYMAN REFRIGERATION (JR) EXAM
COMPLETE EXAM QUESTIONS AND VERIFIED ANSWERS |
2026–2027 LATEST UPDATE | GUARANTEED PASS | DETAILED
RATIONALES | FULL STUDY GUIDE | EXAM PREP | PRACTICE
TEST | CERTIFICATION PREPARATION
SECTION ONE — QUESTIONS 1–100
1. What is the primary function of the compressor in a vapor-compression refrigeration cycle?
A) To condense refrigerant vapor into liquid
B) To absorb heat from the refrigerated space
C) To increase the pressure and temperature of refrigerant vapor
D) To expand refrigerant to reduce pressure
Correct Answer: C) To increase the pressure and temperature of refrigerant vapor
Rationale: The compressor draws in low-pressure, low-temperature refrigerant vapor from the
evaporator and compresses it, raising both its pressure and temperature before discharging it to the
condenser. This pressure increase is essential to enable the refrigerant to reject heat at ambient
temperatures. Options A, B, and D describe functions of other system components (condenser,
evaporator, and metering device, respectively).
2. Which refrigerant classification under ASHRAE Standard 34 denotes no flame propagation?
A) A1
B) A2
C) B1
D) B2
Correct Answer: A) A1
Rationale: ASHRAE Standard 34 uses a two-character safety classification where "A" indicates low
toxicity and "1" indicates no flame propagation. R-134a and R-410A are examples of A1 refrigerants.
The "B" designation indicates higher toxicity, while numbers 2 and 3 indicate increasing flammability
levels. This classification is critical for safe refrigerant selection and handling.
3. A technician is troubleshooting a system with high head pressure and observes a dirty
condenser coil. Which of the following is the most likely consequence of this condition?
A) Low suction pressure
B) Reduced system efficiency and potential compressor overheating
C) Increased subcooling
D) Decreased refrigerant flow through the expansion valve
Correct Answer: B) Reduced system efficiency and potential compressor overheating
Rationale: A dirty condenser coil restricts heat rejection, causing the condensing temperature and
pressure to rise. This increases compressor work and discharge temperature, reducing efficiency and
,potentially leading to compressor damage. Low suction pressure is not a direct consequence of a dirty
condenser—it more often indicates low refrigerant charge or restricted airflow over the evaporator.
4. In New Mexico, which agency has the authority to enforce the state mechanical code on a
construction site?
A) The General Contractor
B) The local Fire Marshal only
C) The Construction Industries Division (CID) or local jurisdiction inspector
D) The Environmental Protection Agency (EPA)
Correct Answer: C) The Construction Industries Division (CID) or local jurisdiction inspector
Rationale: The New Mexico Regulation and Licensing Department's Construction Industries Division
(CID) holds authority to inspect work and enforce code compliance for mechanical and refrigeration
systems. Local jurisdictions may also have inspectors authorized to enforce these codes. The EPA
regulates refrigerant handling but does not enforce mechanical installation codes.
5. What is the approximate COP of a Carnot refrigeration system operating between 10°F and
100°F?
A) 2.0
B) 5.0
C) 7.0
D) 10.0
Correct Answer: B) 5.0
Rationale: The Carnot COP is calculated as T_evap ÷ (T_cond – T_evap) using absolute temperatures
in Rankine. Convert 10°F to 470°R and 100°F to 560°R: COP = 470 ÷ (560 – 470) = 470 ÷ 90 = 5.22,
approximately 5.0. This theoretical maximum helps technicians understand that real systems operate
at lower efficiencies due to irreversibilities.
6. What is the state of refrigerant as it leaves the evaporator in a properly operating system?
A) Low-pressure, high-temperature liquid
B) High-pressure, low-temperature vapor
C) Low-pressure, low-temperature vapor with some superheat
D) High-pressure, high-temperature liquid
Correct Answer: C) Low-pressure, low-temperature vapor with some superheat
Rationale: Refrigerant leaves the evaporator as a low-pressure, low-temperature vapor that has
absorbed sufficient heat to become slightly superheated. This ensures no liquid returns to the
compressor, which would cause slugging and potential damage. Options A and D describe liquid
states found elsewhere in the cycle, while B incorrectly describes the state at the evaporator outlet.
7. A system administrator notices a three-phase compressor drawing low amperage with no
pressure differential. What is the most likely cause?
A) Normal operation
B) Extremely high head pressure
C) The compressor is rotating backwards
D) A refrigerant overcharge
Correct Answer: C) The compressor is rotating backwards
, Rationale: A reversed scroll or reciprocating compressor will not pump refrigerant effectively. The
amperage will be significantly lower than normal because the compressor is operating unloaded, and
there will be no measurable pressure difference between suction and discharge. High head pressure
would typically increase amp draw, while an overcharge would also show abnormal pressures.
8. Which metering device is most commonly used on a residential heat pump operating in both
heating and cooling modes?
A) Capillary tube
B) Fixed orifice (piston)
C) Thermostatic expansion valve (TXV)
D) Hand expansion valve
Correct Answer: C) Thermostatic expansion valve (TXV)
Rationale: Heat pumps require efficient operation in both heating and cooling modes. A TXV with a
check valve or a bi-flow design provides proper refrigerant metering in both flow directions,
maintaining superheat across varying operating conditions. Capillary tubes and fixed orifices cannot
adapt to the different pressures and flows encountered in heat pump operation.
9. What is the primary purpose of a filter-drier in a refrigeration system?
A) To increase refrigerant pressure
B) To remove moisture and particulate contaminants from the refrigerant
C) To store liquid refrigerant
D) To regulate refrigerant flow
Correct Answer: B) To remove moisture and particulate contaminants from the refrigerant
Rationale: Filter-driers contain desiccant material that adsorbs moisture and traps solid contaminants
to protect system components from corrosion, acid formation, and freeze-ups. This is essential for
maintaining system reliability and preventing compressor failure. Options A, C, and D describe
functions of other components such as the compressor, receiver, and expansion valve.
10. What does one BTU (British Thermal Unit) represent?
A) The heat required to raise 1 pound of water by 1°F
B) The heat required to melt 1 pound of ice
C) The heat required to boil 1 pound of water
D) The heat required to raise 1 gram of water by 1°C
Correct Answer: A) The heat required to raise 1 pound of water by 1°F
Rationale: One BTU is defined as the amount of heat required to raise the temperature of one pound
of water by one degree Fahrenheit. This is a fundamental unit in refrigeration and HVAC calculations.
The other options describe different quantities: melting ice requires 144 BTU/lb, boiling water
requires 970 BTU/lb, and option D describes a calorie.
11. What is the most likely result of a "flooded start" in a compressor?
A) The compressor runs with high superheat
B) Liquid refrigerant washes the oil off the bearings
C) The discharge pressure drops below the saturation point
D) The condenser becomes blocked
Correct Answer: B) Liquid refrigerant washes the oil off the bearings
COMPLETE EXAM QUESTIONS AND VERIFIED ANSWERS |
2026–2027 LATEST UPDATE | GUARANTEED PASS | DETAILED
RATIONALES | FULL STUDY GUIDE | EXAM PREP | PRACTICE
TEST | CERTIFICATION PREPARATION
SECTION ONE — QUESTIONS 1–100
1. What is the primary function of the compressor in a vapor-compression refrigeration cycle?
A) To condense refrigerant vapor into liquid
B) To absorb heat from the refrigerated space
C) To increase the pressure and temperature of refrigerant vapor
D) To expand refrigerant to reduce pressure
Correct Answer: C) To increase the pressure and temperature of refrigerant vapor
Rationale: The compressor draws in low-pressure, low-temperature refrigerant vapor from the
evaporator and compresses it, raising both its pressure and temperature before discharging it to the
condenser. This pressure increase is essential to enable the refrigerant to reject heat at ambient
temperatures. Options A, B, and D describe functions of other system components (condenser,
evaporator, and metering device, respectively).
2. Which refrigerant classification under ASHRAE Standard 34 denotes no flame propagation?
A) A1
B) A2
C) B1
D) B2
Correct Answer: A) A1
Rationale: ASHRAE Standard 34 uses a two-character safety classification where "A" indicates low
toxicity and "1" indicates no flame propagation. R-134a and R-410A are examples of A1 refrigerants.
The "B" designation indicates higher toxicity, while numbers 2 and 3 indicate increasing flammability
levels. This classification is critical for safe refrigerant selection and handling.
3. A technician is troubleshooting a system with high head pressure and observes a dirty
condenser coil. Which of the following is the most likely consequence of this condition?
A) Low suction pressure
B) Reduced system efficiency and potential compressor overheating
C) Increased subcooling
D) Decreased refrigerant flow through the expansion valve
Correct Answer: B) Reduced system efficiency and potential compressor overheating
Rationale: A dirty condenser coil restricts heat rejection, causing the condensing temperature and
pressure to rise. This increases compressor work and discharge temperature, reducing efficiency and
,potentially leading to compressor damage. Low suction pressure is not a direct consequence of a dirty
condenser—it more often indicates low refrigerant charge or restricted airflow over the evaporator.
4. In New Mexico, which agency has the authority to enforce the state mechanical code on a
construction site?
A) The General Contractor
B) The local Fire Marshal only
C) The Construction Industries Division (CID) or local jurisdiction inspector
D) The Environmental Protection Agency (EPA)
Correct Answer: C) The Construction Industries Division (CID) or local jurisdiction inspector
Rationale: The New Mexico Regulation and Licensing Department's Construction Industries Division
(CID) holds authority to inspect work and enforce code compliance for mechanical and refrigeration
systems. Local jurisdictions may also have inspectors authorized to enforce these codes. The EPA
regulates refrigerant handling but does not enforce mechanical installation codes.
5. What is the approximate COP of a Carnot refrigeration system operating between 10°F and
100°F?
A) 2.0
B) 5.0
C) 7.0
D) 10.0
Correct Answer: B) 5.0
Rationale: The Carnot COP is calculated as T_evap ÷ (T_cond – T_evap) using absolute temperatures
in Rankine. Convert 10°F to 470°R and 100°F to 560°R: COP = 470 ÷ (560 – 470) = 470 ÷ 90 = 5.22,
approximately 5.0. This theoretical maximum helps technicians understand that real systems operate
at lower efficiencies due to irreversibilities.
6. What is the state of refrigerant as it leaves the evaporator in a properly operating system?
A) Low-pressure, high-temperature liquid
B) High-pressure, low-temperature vapor
C) Low-pressure, low-temperature vapor with some superheat
D) High-pressure, high-temperature liquid
Correct Answer: C) Low-pressure, low-temperature vapor with some superheat
Rationale: Refrigerant leaves the evaporator as a low-pressure, low-temperature vapor that has
absorbed sufficient heat to become slightly superheated. This ensures no liquid returns to the
compressor, which would cause slugging and potential damage. Options A and D describe liquid
states found elsewhere in the cycle, while B incorrectly describes the state at the evaporator outlet.
7. A system administrator notices a three-phase compressor drawing low amperage with no
pressure differential. What is the most likely cause?
A) Normal operation
B) Extremely high head pressure
C) The compressor is rotating backwards
D) A refrigerant overcharge
Correct Answer: C) The compressor is rotating backwards
, Rationale: A reversed scroll or reciprocating compressor will not pump refrigerant effectively. The
amperage will be significantly lower than normal because the compressor is operating unloaded, and
there will be no measurable pressure difference between suction and discharge. High head pressure
would typically increase amp draw, while an overcharge would also show abnormal pressures.
8. Which metering device is most commonly used on a residential heat pump operating in both
heating and cooling modes?
A) Capillary tube
B) Fixed orifice (piston)
C) Thermostatic expansion valve (TXV)
D) Hand expansion valve
Correct Answer: C) Thermostatic expansion valve (TXV)
Rationale: Heat pumps require efficient operation in both heating and cooling modes. A TXV with a
check valve or a bi-flow design provides proper refrigerant metering in both flow directions,
maintaining superheat across varying operating conditions. Capillary tubes and fixed orifices cannot
adapt to the different pressures and flows encountered in heat pump operation.
9. What is the primary purpose of a filter-drier in a refrigeration system?
A) To increase refrigerant pressure
B) To remove moisture and particulate contaminants from the refrigerant
C) To store liquid refrigerant
D) To regulate refrigerant flow
Correct Answer: B) To remove moisture and particulate contaminants from the refrigerant
Rationale: Filter-driers contain desiccant material that adsorbs moisture and traps solid contaminants
to protect system components from corrosion, acid formation, and freeze-ups. This is essential for
maintaining system reliability and preventing compressor failure. Options A, C, and D describe
functions of other components such as the compressor, receiver, and expansion valve.
10. What does one BTU (British Thermal Unit) represent?
A) The heat required to raise 1 pound of water by 1°F
B) The heat required to melt 1 pound of ice
C) The heat required to boil 1 pound of water
D) The heat required to raise 1 gram of water by 1°C
Correct Answer: A) The heat required to raise 1 pound of water by 1°F
Rationale: One BTU is defined as the amount of heat required to raise the temperature of one pound
of water by one degree Fahrenheit. This is a fundamental unit in refrigeration and HVAC calculations.
The other options describe different quantities: melting ice requires 144 BTU/lb, boiling water
requires 970 BTU/lb, and option D describes a calorie.
11. What is the most likely result of a "flooded start" in a compressor?
A) The compressor runs with high superheat
B) Liquid refrigerant washes the oil off the bearings
C) The discharge pressure drops below the saturation point
D) The condenser becomes blocked
Correct Answer: B) Liquid refrigerant washes the oil off the bearings
