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






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






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






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






5. 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






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






7. The technician observes a pressure drop of 25 degrees across an air conditioning evaporator coil at start-up. This drop would indicate...






8. When troubleshooting a split-system air conditioner - it is found that the compressor motor is humming but not starting. Technician A says that it could be an open internal overload protector. Technician B says that it could be a blown fuse. Which te






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






10. 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






11. 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






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






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






14. 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...






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






16. 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...






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






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






19. Air filters should be replaced...






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






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






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






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






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






25. 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






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






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






28. 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






29. 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






30. What is the purpose of the TXV...






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






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






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






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






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






36. A customer calls with an insufficient cooling complaint on a 90






37. A customer calls with an insufficient cooling complaint. Upon arrival to the service call it is found that the outdoor condensing unit is operating - but the indoor blower is not in operation. Technician A says that it is possible that it is a bad fu






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






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






40. A hard-start kit consists of...






41. 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...






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






43. What is the purpose of an EPR valve...






44. 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






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






46. A hard-start kit consists of...






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






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






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






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