Free practice test — 12 questions with full explanations
Original CraftPATH practice questions. These are not real exam questions. Every answer includes the reasoning, why each wrong option fails, the code area it comes from, and the misconception it targets.
Question 1. A TXV split system shows 2F of subcooling on a 100F day with normal airflow. The most likely condition is:
Refrigeration Cycle and Charging · Medium · Objective: Interpret subcooling.
- A. Overcharge
- B. Undercharge (correct)
- C. Restricted liquid line filter drier
- D. Failed capacitor
Correct answer: B. Undercharge
Why this is right: A TXV controls superheat, so charge is verified by subcooling. Low subcooling means liquid is not backing up in the condenser, which points to an undercharge.
Why the other options are wrong:
- A. Overcharge — An overcharge raises subcooling above the target, not below it.
- C. Restricted liquid line filter drier — A restricted drier typically produces a temperature drop across the drier and elevated subcooling upstream, not low subcooling.
- D. Failed capacitor — A failed run capacitor causes hard starting or a locked rotor, not a subcooling reading of 2F with normal operation.
Where this shows up on the job: On TXV equipment, technicians who chase superheat instead of subcooling routinely overcharge systems and flood compressors on the next cool morning.
Code reference: Manufacturer charging charts; 40 CFR Part 82 Subpart F refrigerant handling
Common misconception: Using superheat to verify charge on a TXV or EEV system.
Question 2. Before opening a small appliance containing regulated refrigerant for major repair, a technician must recover:
Refrigeration Cycle and Charging · Hard · Objective: Apply refrigerant recovery rules.
- A. No refrigerant if the system is already low
- B. Refrigerant to the level required by the EPA recovery requirements for that appliance type (correct)
- C. Only the vapor charge
- D. Refrigerant only if the customer requests it
Correct answer: B. Refrigerant to the level required by the EPA recovery requirements for that appliance type
Why this is right: Federal rules prohibit knowingly venting regulated refrigerant and require evacuation to the specified level for the appliance type and recovery equipment before opening the system.
Why the other options are wrong:
- A. No refrigerant if the system is already low — A low charge does not exempt the system; remaining refrigerant must still be recovered.
- C. Only the vapor charge — Both liquid and vapor must be recovered, not vapor alone.
- D. Refrigerant only if the customer requests it — Recovery is a federal requirement, not a customer option.
Where this shows up on the job: Venting violations carry federal penalties per day per violation, and recovery records are the first thing an inspector asks for.
Code reference: 40 CFR Part 82 Subpart F; EPA Section 608 technician certification
Common misconception: Believing a system that already leaked out is exempt from recovery.
Question 3. A system moves 1,200 CFM with a 20F temperature drop across the evaporator. The approximate sensible capacity is:
Airflow and Load Calculation · Medium · Objective: Apply the sensible heat equation.
- A. 12,960 BTU/h
- B. 19,440 BTU/h
- C. 25,920 BTU/h (correct)
- D. 36,000 BTU/h
Correct answer: C. 25,920 BTU/h
Why this is right: Sensible heat equals 1.08 x CFM x temperature difference. 1.08 x 1,200 x 20 = 25,920 BTU/h.
Why the other options are wrong:
- A. 12,960 BTU/h — 12,960 results from using a 10F drop instead of 20F.
- B. 19,440 BTU/h — 19,440 results from using 900 CFM instead of 1,200.
- D. 36,000 BTU/h — 36,000 is the nominal three-ton rating, which is total capacity, not the calculated sensible output.
Where this shows up on the job: The 1.08 relationship is how you tell whether a unit is actually delivering rated capacity, or whether a duct problem is hiding behind a nameplate.
Code reference: Standard psychrometric sensible heat relationship; ACCA Manual J and Manual D
Common misconception: Confusing calculated sensible capacity with the nominal total tonnage on the nameplate.
Question 4. The correct sequence for designing a residential system is:
Airflow and Load Calculation · Medium · Objective: Order the design process.
- A. Manual D, then Manual J, then Manual S
- B. Manual J, then Manual S, then Manual D (correct)
- C. Manual S, then Manual D, then Manual J
- D. Manual D only, since duct size sets everything
Correct answer: B. Manual J, then Manual S, then Manual D
Why this is right: Manual J establishes the load, Manual S selects equipment that matches that load, and Manual D sizes the duct system to deliver the selected equipment's airflow.
Why the other options are wrong:
- A. Manual D, then Manual J, then Manual S — Sizing ducts before knowing the load or the equipment is backwards.
- C. Manual S, then Manual D, then Manual J — You cannot select equipment before calculating the load.
- D. Manual D only, since duct size sets everything — Duct design alone cannot determine equipment capacity.
Where this shows up on the job: Rule-of-thumb tonnage per square foot is still the most common cause of short-cycling, humidity complaints, and callbacks in Texas humidity.
Code reference: ACCA Manual J, Manual S, and Manual D
Common misconception: Sizing equipment by square footage rather than a room-by-room load calculation.
Question 5. A condensing unit nameplate lists MCA 24.6 and MOCP 40. The correct installation is:
Electrical · Medium · Objective: Read nameplate data.
- A. 10 AWG conductors with a 25-amp breaker
- B. 10 AWG conductors with a maximum 40-amp breaker (correct)
- C. 14 AWG conductors with a 40-amp breaker
- D. 8 AWG conductors with a 60-amp breaker
Correct answer: B. 10 AWG conductors with a maximum 40-amp breaker
Why this is right: Conductors must have an ampacity of at least the minimum circuit ampacity of 24.6 amps, and the overcurrent device may not exceed the maximum overcurrent protection of 40 amps.
Why the other options are wrong:
- A. 10 AWG conductors with a 25-amp breaker — A 25-amp breaker is permissible but the question asks for a compliant option; the more complete answer is conductors sized to MCA with protection not exceeding MOCP. A 25-amp device may nuisance trip on locked rotor.
- C. 14 AWG conductors with a 40-amp breaker — 14 AWG cannot carry 24.6 amps and would be badly undersized behind a 40-amp device.
- D. 8 AWG conductors with a 60-amp breaker — Exceeding the MOCP of 40 amps violates the listing.
Where this shows up on the job: MOCP exists because compressors draw locked-rotor current on start; a breaker sized only to running load will trip on hot afternoons.
Code reference: NEC Article 440, air conditioning and refrigeration equipment; equipment nameplate listing
Common misconception: Sizing the breaker to the conductor instead of to the equipment nameplate MOCP.
Question 6. A 24-volt control transformer repeatedly fails on a rooftop unit. The most probable cause is:
Electrical · Hard · Objective: Diagnose a control circuit.
- A. An oversized transformer
- B. A shorted thermostat wire or contactor coil drawing excess VA (correct)
- C. Line voltage that is too low
- D. A dirty condenser coil
Correct answer: B. A shorted thermostat wire or contactor coil drawing excess VA
Why this is right: Repeated transformer failure indicates the secondary is overloaded, most often from chafed control wiring shorting to the cabinet or a shorted contactor coil.
Why the other options are wrong:
- A. An oversized transformer — An oversized transformer runs cooler, not hotter.
- C. Line voltage that is too low — Low line voltage reduces secondary output but does not typically destroy the transformer.
- D. A dirty condenser coil — A dirty coil affects head pressure and compressor amps, not the control transformer.
Where this shows up on the job: On rooftops, the thermostat wire rubbing where it enters the curb is the single most common cause of a burned control transformer.
Code reference: Equipment wiring diagrams; NEC Article 725 for Class 2 control circuits
Common misconception: Replacing the transformer repeatedly without ohming out the secondary load.
Question 7. A gas furnace installed in a small closet with no outside air openings is most at risk of:
Combustion and Venting · Hard · Objective: Identify combustion air requirements.
- A. Excess airflow across the heat exchanger
- B. Insufficient combustion air causing incomplete combustion and CO production (correct)
- C. Refrigerant migration
- D. Excessive subcooling
Correct answer: B. Insufficient combustion air causing incomplete combustion and CO production
Why this is right: Confined spaces must be provided combustion air by the methods the fuel gas code prescribes; without it, combustion becomes oxygen-starved and produces carbon monoxide.
Why the other options are wrong:
- A. Excess airflow across the heat exchanger — Closet size does not increase airflow across the heat exchanger.
- C. Refrigerant migration — Refrigerant migration is a cooling-side issue unrelated to combustion air.
- D. Excessive subcooling — Subcooling is a refrigeration measurement, not a combustion condition.
Where this shows up on the job: Furnaces in converted closets and attic knee-walls are where CO incidents actually happen, and the fix is nearly always combustion air, not the burner.
Code reference: National Fuel Gas Code (NFPA 54), combustion air provisions
Common misconception: Assuming a louvered door alone satisfies the combustion air requirement without checking the required free area.
Question 8. A Category I gas appliance is one that operates with:
Combustion and Venting · Medium · Objective: Categorize appliance venting.
- A. Positive vent pressure and a non-condensing flue
- B. Non-positive vent pressure and a flue gas temperature above the dew point (correct)
- C. Positive vent pressure and condensing flue gas
- D. Direct electric heat with no flue
Correct answer: B. Non-positive vent pressure and a flue gas temperature above the dew point
Why this is right: Category I appliances vent under non-positive pressure with flue gas temperatures high enough to avoid condensation, which is why they use Type B vent or a masonry chimney.
Why the other options are wrong:
- A. Positive vent pressure and a non-condensing flue — Positive vent pressure with a non-condensing flue describes Category III.
- C. Positive vent pressure and condensing flue gas — Positive pressure with condensing flue gas describes Category IV, which uses sealed plastic venting.
- D. Direct electric heat with no flue — Electric heat is not vented and has no category.
Where this shows up on the job: Mixing a Category IV furnace into an existing Type B vent, or orphaning a water heater on an oversized chimney after a furnace upgrade, are the two classic venting failures on changeouts.
Code reference: National Fuel Gas Code (NFPA 54), venting categories and sizing tables
Common misconception: Reusing existing venting on a changeout without re-running the vent sizing tables.
Question 9. In Texas, the difference between a Class A and a Class B air conditioning and refrigeration contractor license is:
Texas ACR Licensing · Medium · Objective: Distinguish license classes.
- A. Class A is residential only
- B. Class B is limited by equipment size, while Class A is unlimited (correct)
- C. Class B allows commercial refrigeration only
- D. There is no difference
Correct answer: B. Class B is limited by equipment size, while Class A is unlimited
Why this is right: A Class B license limits the technician to equipment within specified cooling and heating capacity limits, while a Class A license carries no such equipment size limitation.
Why the other options are wrong:
- A. Class A is residential only — Class A is the unlimited license, not a residential-only license.
- C. Class B allows commercial refrigeration only — Class B is a size-limited license, not a refrigeration-only license.
- D. There is no difference — The classes differ specifically on equipment capacity limits.
Where this shows up on the job: Contractors who grow into light commercial work discover the Class B ceiling the first time they bid a 30-ton rooftop.
Code reference: Texas Occupations Code, Chapter 1302; TDLR air conditioning and refrigeration rules
Common misconception: Assuming Class B covers any job as long as it is residential.
Question 10. Texas ACR contractor licenses carry endorsements for:
Texas ACR Licensing · Medium · Objective: Identify endorsements.
- A. Environmental air conditioning, commercial refrigeration and process cooling or heating, or both (correct)
- B. Residential and commercial only
- C. New construction and service only
- D. Gas and electric only
Correct answer: A. Environmental air conditioning, commercial refrigeration and process cooling or heating, or both
Why this is right: TDLR issues ACR contractor licenses with an environmental air conditioning endorsement, a commercial refrigeration and process cooling or heating endorsement, or both.
Why the other options are wrong:
- B. Residential and commercial only — Residential versus commercial is not how the endorsements are defined.
- C. New construction and service only — New construction and service is not an endorsement category.
- D. Gas and electric only — Fuel type is not an endorsement category.
Where this shows up on the job: Supermarket rack and cold-storage work requires the commercial refrigeration endorsement, which many comfort-cooling contractors never hold.
Code reference: Texas Occupations Code, Chapter 1302; TDLR ACR program rules
Common misconception: Believing one ACR license automatically covers both comfort cooling and commercial refrigeration.
Question 11. Air conditioning and refrigeration contractor licenses in Texas are issued by:
Texas ACR Licensing · Easy · Objective: Identify the licensing authority.
- A. The Texas State Board of Plumbing Examiners
- B. The Texas Department of Licensing and Regulation (TDLR) (correct)
- C. Each city's mechanical board
- D. The EPA
Correct answer: B. The Texas Department of Licensing and Regulation (TDLR)
Why this is right: TDLR administers the Air Conditioning and Refrigeration Contractor License program under Chapter 1302 of the Texas Occupations Code.
Why the other options are wrong:
- A. The Texas State Board of Plumbing Examiners — TSBPE licenses plumbers.
- C. Each city's mechanical board — Cities issue permits and inspect work but do not issue the state ACR license.
- D. The EPA — The EPA issues Section 608 technician certification, not a state contractor license.
Where this shows up on the job: You need both: TDLR for the contractor license and EPA 608 for refrigerant handling. They are separate credentials with separate rules.
Code reference: Texas Occupations Code, Chapter 1302
Common misconception: Confusing EPA Section 608 certification with a state contractor license.
Question 12. A Texas ACR contractor license requires the license holder to maintain:
Texas Mechanical Code and Business · Medium · Objective: Apply insurance requirements.
- A. No insurance if working residential only
- B. Commercial general liability insurance at the minimum amounts the state sets (correct)
- C. A performance bond on every job
- D. Workers compensation on all jobs without exception
Correct answer: B. Commercial general liability insurance at the minimum amounts the state sets
Why this is right: Texas requires ACR contractors to carry commercial general liability insurance meeting statutory minimums as a condition of licensure.
Why the other options are wrong:
- A. No insurance if working residential only — The insurance requirement is not waived for residential work.
- C. A performance bond on every job — Per-job performance bonds are a contract matter, not a licensing requirement.
- D. Workers compensation on all jobs without exception — Texas does not universally mandate workers compensation for private employers, though many contracts require it.
Where this shows up on the job: Letting the liability policy lapse suspends the license, and most homeowners' insurers will deny a claim on unlicensed mechanical work.
Code reference: Texas Occupations Code, Chapter 1302; TDLR ACR administrative rules
Common misconception: Assuming a general business policy satisfies the specific statutory coverage requirement.
How to study for the Texas ACR contractor exam
Decide Class A or Class B before you study
The class you apply for determines the equipment capacity you may work on and shapes what the exam emphasizes for you. Class A carries no equipment size limit and is what you need for larger commercial work. Confirm the current capacity limits for Class B with TDLR, then pick the endorsement or endorsements that match the work you actually sell, because commercial refrigeration and environmental air conditioning are tested as different bodies of knowledge.
Make the refrigeration measurements automatic
Superheat and subcooling questions are the highest-yield material on any HVAC exam. Know cold which measurement verifies charge for a fixed orifice versus a TXV or EEV, what high and low readings each indicate, and how airflow problems mimic charge problems. Practice reading a pressure-temperature chart quickly, and know the recovery and evacuation requirements that come from federal refrigerant rules.
Own the two formulas that keep appearing
Sensible heat equals 1.08 times CFM times temperature difference. Total heat equals 4.5 times CFM times enthalpy difference. Between them they answer a large share of airflow and capacity questions. Then learn the Manual J, S, D sequence as a design discipline, because the exam tests the order and the reasoning, not just the arithmetic.
Study combustion as a safety subject
Combustion air, appliance venting categories, vent sizing, and carbon monoxide questions are written to be missed. Learn what defines a confined space, the prescribed methods for supplying combustion air and their required free areas, and the four appliance categories with the venting material each one requires. Changeout scenarios where a high-efficiency furnace orphans a water heater on a shared chimney are a favorite question format.
Read Chapter 1302 and the TDLR rules directly
The statutes and rules portion is pure recall and is the easiest place to bank points. Know the license classes and endorsements, the insurance requirement, technician registration, what a licensed contractor is responsible for, advertising and permit rules, and the continuing education needed for renewal. Read the statute itself rather than a summary.
Run a five-week plan with timed sets
Week one: refrigeration cycle and charging. Week two: airflow, load calculation and duct design. Week three: electrical and controls. Week four: combustion, venting and the mechanical code. Week five: Chapter 1302, business rules, and full-length timed mixed sets at roughly one question per minute.
Frequently asked questions
What is the difference between a Texas Class A and Class B ACR license?
Class A carries no equipment capacity limit. Class B limits you to equipment within specified cooling and heating capacities. Confirm the current limits with TDLR, since they are set by rule.
Do I need EPA 608 certification as well?
Yes. EPA Section 608 technician certification is a separate federal credential required to handle regulated refrigerants. The state contractor license does not replace it.
How many questions are on the Texas ACR contractor exam?
TDLR and its examination vendor publish item counts and passing scores in the current candidate information bulletin. We mark those pending rather than repeating unsourced numbers.
Which endorsement should I choose?
Environmental air conditioning covers comfort cooling and heating. Commercial refrigeration and process cooling or heating covers refrigeration systems such as supermarket and cold-storage work. You can hold both.
Does Texas require insurance for an ACR license?
Yes. Chapter 1302 requires the license holder to maintain commercial general liability insurance at the statutory minimum amounts, and a lapse can suspend the license.
Are these real TDLR exam questions?
No. Every question here is original CraftPATH material written to the same subject areas the exam covers. We do not reproduce live examination content.
How long should I study?
Experienced technicians typically need four to six weeks, weighted toward load calculation, combustion and venting, and the statutes and rules section that field work never teaches you.