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






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 on a 90






4. 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






5. 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...






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






7. 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






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






9. 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






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






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






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






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






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






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






16. 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






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






18. Air filters should be replaced...






19. What is the purpose of the TXV...






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






21. 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






22. A customer who owns a split air conditioning system complains that his system has been running but his house doesn't seem to be cooling properly. When the service technician arrives on the job - he or she finds that the indoor blower is operating and






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






24. A hard-start kit for an air conditioning system...






25. 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...






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






27. A hard-start kit for an air conditioning system...






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






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






30. 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






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






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






33. 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






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






35. 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...






36. 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






37. 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...






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






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






40. 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






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






42. 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






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






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






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






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






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






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






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