Test your basic knowledge |

NATE Air Conditioning Troubleshooting

Subjects : engineering, nate
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. A system that uses a thermal electric expansion valve...






2. What are two common problems that can cause a sight glass in an air conditioning to have bubbles...






3. Superheat is found in an air conditioning system in the...






4. Technician A says that if you connect 208 volts to the primary side of a 240-volt/ 24-volt transformer - the transformer will burn out. Technician B says that if you connect 208 volts to the primary side of a 240-volt/24-volt transformer - the contro






5. A customer calls and complains that her high-efficiency air conditioning system is operating - but is not cooling properly. Further investigation shows that the system is using a TXV type of metering device. A subcooling check shows that the system a






6. What is the purpose of a CPR valve...






7. What are three methods for controlling a system's high-side pressure during low ambient conditions...






8. What are two problems that can cause an air conditioning system to have an excessively high superheat...






9. A customer calls and says that her air conditioning system is not cooling properly. Upon arrival - a technician notices that the suction line and compressor have frost buildup. Technician A says that the problem is probably a low charge. Technician B






10. Which of the following can cause low superheat in a TXV system...






11. A compressor motor starts and operates for a short period of time and cycles on the external overload protector. What are two possible problems that could cause this...






12. What are two problems that can cause an air conditioning system to have an excessively high superheat...






13. Why is it unsafe to operate an air conditioning system with a low charge...






14. What are the operating pressures of an oil pressure safety switch...






15. What are the symptoms of an air conditioning system that has a bad compressor discharge valve...






16. Name two symptoms that are common to an over-charged air conditioning system and a system that has a dirty condenser.






17. A rooftop package system keeps tripping out on the high-pressure switch. What are three possible causes for this problem...






18. What are the symptoms of an air conditioning system that has a low charge...






19. The best description of a relay would be...






20. Which of the following is a common cause of an excessively low superheat on a TXV system...






21. What is a common temperature difference between the condensing temperature on an air-cooled condensing unit and the outdoor ambient temperature...






22. An air conditioning unit has a suction line that is frosted up to the compressor. What faults could cause this to occur...






23. Which of the following could be the cause for a system's discharge and suction pressure being low...






24. What type of problems can be caused by an oversized air conditioning system...






25. What are three methods for controlling a system's high-side pressure during low ambient conditions...






26. What are the symptoms of an air conditioning system that has a low charge...






27. After a compressor motor has been severely burnt - What accessory must be added as an aid to rid the air conditioning system of acid...






28. If 24 volts are present to the contactor coil on an air conditioning system and the condenser fan or compressor is inoperative - which of the following could be at fault...






29. Insufficient airflow can be caused by...






30. An air conditioning system that uses a fan center has an inoperable indoor blower. When the thermostat is set for cooling and dialed below room temperature - a test with the voltmeter shows that there is 24 volts across terminals 'are' and 'G' at the






31. Which of the following is a common cause of an excessively low superheat on a TXV system...






32. What three things can prevent an air conditioning system from releasing heat at the proper rate...






33. Which of the following could be the cause for a system's discharge and suction pressure being low...






34. A customer calls with an insufficient cooling complaint. Upon arrival to the service call it is found that the system is using are-22 with the high-side pressure at 290 psig and the low-side pressure at 85 psig. The ambient temperature is 85






35. Name two symptoms that are common to an over-charged air conditioning system and a system that has a dirty condenser.






36. On an are-22 air conditioning system - the suction-line filter drier should be changed when the pressure drop dictates...






37. What type of problems can be caused by an oversized air conditioning system...






38. What are the operating pressures of an oil pressure safety switch...






39. A compressor motor starts and operates for a short period of time and cycles on the external overload protector. What are two possible problems that could cause this...






40. What is a common discharge temperature of an air-cooled air conditioning system that is used on a 90






41. What controls are used on air conditioning or refrigeration systems that incorporate an automatic pump-down system...






42. Which of the following can cause low superheat in a TXV system...






43. A customer calls to complain that his central air conditioning system is not cooling properly. The technician arrives on the job. He or she notices that the indoor blower has adequate airflow and the outdoor condenser fan is operating - but the compr






44. A technician receives an air conditioning service call stating that the system is operating but isn't cooling properly. When the technician arrives - she notices that the compressor has recently been changed and it is an are-22 system. She checks the






45. A split-system air conditioner that uses a piston-type metering device is to be charged with are-22. Technician A says that the outdoor dry-bulb temperature is needed to determine the proper superheat. Technician B says that the indoor wet-bulb tempe






46. A commercial customer calls on a 90






47. Air filters should be replaced...






48. A customer calls and complains that his air conditioning system is not operating properly. It is noticed that the compressor is not operating. A check on the run capacitor shows that there is 33 uf and the rating on the capacitor is 40 uf. Technician






49. Air filters should be replaced...






50. If a TXV sensing bulb had lost its charge - what effect would this have on the air conditioning system...