Air Conditioning Repair Study Guide 2026
Everything you need to pass the Air Conditioning Repair exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 Air Conditioning Repair Exam Format at a Glance
📚 Air Conditioning Repair Topics to Study (49)
✍️ Sample Air Conditioning Repair Questions & Answers
1. What is the correct procedure for adding refrigerant to a car AC system that is slightly low?
Refrigerant is added as a gas (or low-pressure liquid from an inverted can) to the low-side service port with the engine running and AC on max, never to the high side.
2. Which component's failure would most likely cause high superheat AND high subcooling simultaneously?
A restriction in the liquid line or a clogged filter drier causes refrigerant to back up (high subcooling) before the restriction and starve the evaporator (high superheat) after it.
3. An HVAC technician measures 0V AC between the R and C terminals at the air handler control board with the disconnect closed. What does this indicate?
No voltage between R and C with power applied means the 24V transformer is not producing output, either due to a failed transformer or no primary voltage reaching it.
4. After recharging, a technician notices the AC vent temperature is warmer than expected despite correct refrigerant charge. What component should be inspected next?
A clogged or bent condenser prevents adequate heat rejection, raising refrigerant temperature and reducing the system's ability to produce cold air even with a proper charge.
5. When replacing an AC compressor, why must a specific amount of oil be added to the new unit?
Old system components (condenser, evaporator, lines) retain a portion of compressor oil, so the replacement compressor must be pre-filled to match total system oil capacity.
6. What happens in a condenser in a cooling and refrigeration system?
In a condenser, the high-pressure, high-temperature gaseous refrigerant releases its latent heat to the cooler ambient air, typically aided by a fan. As it releases this heat, the refrigerant changes phase from a gas back into a liquid. This process is essential for dissipating the heat absorbed from the cabin and completing the refrigeration cycle.