Studying for an HVAC technician certification or an air conditioning repair knowledge exam? This free Air Conditioning Repair Practice Test PDF covers the core topics tested on EPA 608, state HVAC licensing exams, and trade school competency assessments. Download it, print it, and study the material wherever you are — no internet needed.
Air conditioning repair exams test both theoretical knowledge and practical application: you need to understand the refrigeration cycle, identify faults from symptoms, select the right diagnostic approach, and know the EPA regulations that govern refrigerant handling. This PDF organizes all the key domains so you can study systematically and find gaps in your knowledge before test day.
HVAC and AC repair certification exams cover a wide range of topics from refrigeration theory to electrical diagnosis. Below is a breakdown of the major knowledge domains and what you need to know in each area.
Every AC repair exam starts with the fundamentals. You need to know all four stages of the vapor-compression refrigeration cycle: the evaporator absorbs heat from the conditioned space (refrigerant evaporates, cooling the air); the compressor raises the pressure and temperature of the refrigerant vapor; the condenser rejects heat to the outdoors (refrigerant condenses back to liquid); and the expansion valve drops the pressure before the refrigerant re-enters the evaporator. Understand the pressures and temperatures at each stage and what happens when a component fails.
R-22 (HCFC-22) was phased out on January 1, 2020, under the Clean Air Act. Technicians can no longer purchase virgin R-22 — only reclaimed refrigerant is available, at high cost. Modern systems use R-410A (HFC blend, higher operating pressures), R-32 (lower GWP alternative), or the newer R-454B (A2L mildly flammable, low GWP, designated replacement for R-410A in new equipment). EPA Section 608 certification is required by federal law to purchase refrigerants in containers over 2 lbs and to perform refrigerant recovery. Know the four certification categories and the difference between recovery, recycling, and reclaiming.
AC technicians must be able to use a multimeter to measure voltage, amperage, and resistance across components. Key components tested include contactors (magnetic switches that connect compressor and condenser fan motor to line voltage), run and start capacitors (store and release energy to start and run motors), relays (low-voltage control switches), and thermostats (24V control circuit). Know how to test a capacitor for correct microfarad value and how to identify an open or shorted contactor.
Overcharged and undercharged systems are common exam scenarios. The superheat method is used on fixed-metering-device systems (piston/orifice): measure suction line temperature and suction pressure, convert pressure to saturation temperature, calculate superheat (line temp minus saturation temp), and compare to target superheat. The subcooling method is used on TXV (thermostatic expansion valve) systems: measure liquid line temperature and liquid line pressure, convert to saturation temperature, and calculate subcooling (saturation temp minus actual liquid line temp). Target subcooling is typically 10–15°F for most systems.
Refrigerant leaks reduce system efficiency and violate EPA regulations. Electronic leak detectors (heated diode or infrared sensors) are the most common professional tool. UV dye can be injected into the system and detected with a UV light. Nitrogen pressure testing (pushing dry nitrogen through the system and checking for pressure drop) is used during installation and repair. Soap bubbles remain the backup method for pinpointing a leak location already found by another method. Know when each method is appropriate and the EPA rules on venting refrigerants (prohibited except for de minimis releases).
Exam questions often present a set of symptoms and ask you to identify the fault. Key scenarios: low suction pressure + high superheat = low refrigerant charge or restriction; high suction pressure + low superheat = overcharge or oversized metering device; high discharge pressure = dirty condenser coil, non-condensable gases, or refrigerant overcharge; compressor not starting = failed capacitor or open contactor; system running but not cooling = dirty evaporator coil or low airflow from blower motor failure. Practice symptom-to-fault mapping for each major component.
Properly designed duct systems are critical for system efficiency. You should know how to interpret static pressure readings (external static pressure measures airflow resistance through the duct system), how to balance air distribution by adjusting dampers, and how to identify duct leakage (return leaks pull unconditioned air in; supply leaks dump conditioned air into unconditioned spaces, both reducing efficiency and increasing operating costs). Duct leakage testing with a blower door or duct blaster is increasingly tested on state licensing exams.
Print the PDF and work through the questions without looking at the answer key first. Cover the answers and write your own response, then check. For any question you get wrong, go back to the relevant topic section — don't just memorize the answer. Understanding why a symptom points to a specific fault is more valuable than rote memorization, because real exams (and real service calls) will vary the phrasing.
Use this PDF alongside the full interactive AC Repair practice tests on PracticeTestGeeks.com. The online tests give you timed sessions, instant scoring, and detailed explanations for each answer. Combining printable offline review with online timed practice is the most effective preparation strategy for HVAC certification and trade exams.