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. Air filters should be replaced...






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






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






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






5. 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






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






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






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






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






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






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






12. What causes the automatic expansion valve to close...






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






14. 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...






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






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






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






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






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






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






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






22. 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






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






24. 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






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. The internal overload of an air conditioning compressor senses winding temperature and...






27. 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...






28. 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






29. What is the purpose of the TXV...






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






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






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






33. Insufficient airflow can be caused by...






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






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






36. 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...






37. 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






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






39. 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






40. 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






41. The temperature range of the suction line from an air conditioning system should be...






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






43. What is the purpose of the TXV...






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






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






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






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






48. 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






49. 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...






50. 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...