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. What are common methods that are used for leak-testing a system...






2. A restricted air filter in an air conditioning system can be identified by...






3. When testing an indoor blower control circuit and the cooling circuit on a fan center - what terminals should read 24 volts if the air conditioning system is in operation...


4. What are two common symptoms of a rooftop air conditioning system that operates with a reverse-acting high-pressure control stuck in the closed position...






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






6. 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






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






8. If a rooftop air conditioning system does not have any means of low ambient protection - what will be two symptoms of the system when operating under a low ambient condition...






9. A system that is being serviced has been evacuated down to 500 microns. When the gauges are closed and the vacuum pump is turned off - the pressure starts to increase and stops at 1000 microns. Technician A says that the system has a leak and needs t






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






11. What are two common symptoms of refrigerant leaks in an air conditioning system...






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






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






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






15. 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






16. 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






17. 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






18. 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






19. A restricted air filter in an air conditioning system can be identified by...






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






21. When testing an indoor blower control circuit and the cooling circuit on a fan center - what terminals should read 24 volts if the air conditioning system is in operation...


22. When an air conditioning system has an undercharge - what happens to the superheat and the subcooling of the system...






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






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






25. A technician arrives on the job and the customer complains that there is no cooling on his rooftop unit. Troubleshooting the system - the technician finds that the compressor is faulty. He notices that there is another faulty compressor laying next t






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






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






28. Air filters should be replaced...






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






30. What are possible problems that can cause the discharge-line temperature on an air conditioning system to be cool to the touch...






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






32. A system that uses a thermal electric expansion valve...






33. What are two common symptoms of refrigerant leaks in an air conditioning system...






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






35. What are possible problems that can cause the discharge-line temperature on an air conditioning system to be cool to the touch...






36. A technician arrives on the job and the customer complains that there is no cooling on his rooftop unit. Troubleshooting the system - the technician finds that the compressor is faulty. He notices that there is another faulty compressor laying next t






37. 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






38. 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






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






40. A liquid-charged TXV bulb will...






41. 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






42. Which of the following is a possible cause for a compressor to overheat...






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






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






45. Which of the following can cause excessive subcooling...






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






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






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






49. 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






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