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. When using a vapor-charged TXV bulb - it is necessary to have...






2. What types of symptoms will be present if the sensing bulb of a TXV is not properly connected...






3. 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






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






5. What are two common symptoms of an overcharged air conditioning system that uses a capillary-tube-type metering device...






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






7. Technician A says that to manually pump down an air conditioning system with a two-position service valve - the liquid line must be front-seated and the high- and low-side pressure will decrease to 0 psig when the pump-down is complete. Technician B






8. A commercial customer calls complaining that her rooftop air conditioning system is not operating. The technician arrives on the job and sets the thermostat to cooling - then notices that the indoor fan is not operating. The technician then sets the






9. What problem can cause an increase of discharge pressure and an increase of suction pressure...






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






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






12. A commercial customer calls on a 90






13. What is the common cause of a compressor burnout...






14. What is a possible cause of a sweat or frost pattern downstream from a sight glass and filter dryer...






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






16. A commercial customer calls on a 90






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






18. A compressor having tight bearings would cause the current value to...






19. 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...






20. When a high-efficiency split air conditioning system has a plugged metering device - what symptoms might occur...






21. 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...






22. A system that is operating with a clear sight glass shows...






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






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






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






26. 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






27. What are the symptoms of a TXV air conditioning system if it has lost its charge...






28. The technician observes that the compressor is not operating. The compressor windings read 5 ohms start to run - run to common is opened - and start to common is opened. The technician concludes that...






29. Technician A says ' When charging a system using the superheat method - adding refrigerant to the system will increase the superheat.' Technician B says 'When charging a system using the superheat method - adding refrigerant will decrease the superhe






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. What component is most often the cause of a start capacitor failure...






32. An air conditioning system using a fixed-orifice metering device and with noncondensables in the system will cause...






33. What problem or problems can cause low discharge and suction pressure...






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






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






36. Insufficient airflow can be caused by...






37. A 220-volt 30-amp motor circuit keeps tripping the breaker after the motor is started. The starting amperage is 60 amps. When measuring the amperage of the circuit - This is drawn for a brief moment. After startup - the amperage drops to 22 amps and






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






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






40. 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






41. Which of the following problems can cause a decrease in a system's pressures and possible icing of the evaporator coil...






42. What problem or problems can cause the discharge pressure to be low and the suction pressure to be high...






43. 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






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






45. Which of the following problems can cause a decrease in a system's pressures and possible icing of the evaporator coil...






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






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






48. Which of the following will cause excessive discharge pressures on an air conditioning system...






49. What types of symptoms will be present if the sensing bulb of a TXV is not properly connected...






50. Which of the following will cause excessive discharge pressures on an air conditioning system...