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. A commercial customer calls on a 90






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






3. 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






4. 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






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. 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






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






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






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






10. 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






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






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






13. A party-store owner tried to adjust the water valve on his water-cooled condensing unit - then he called for assistance from an HVAC/are service technician. It was found that when servicing the unit - the outlet water temperature was too low. Technic






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






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






16. 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






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






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






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






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






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






22. 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






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






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






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






26. Insufficient airflow can be caused by...






27. 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






28. 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






29. 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






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






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






32. 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






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






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






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






36. 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






37. 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...






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






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






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






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






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






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






44. 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...






45. 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...






46. Insufficient airflow can be caused by...






47. 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






48. Air filters should be replaced...






49. 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






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