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 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






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






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






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






5. 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






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






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






8. 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






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






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






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






12. 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






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






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






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






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






17. A compressor having tight bearings would cause the current value to...






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






19. A commercial customer calls on a 90






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






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






22. An air conditioning system using a fixed-orifice metering device and with noncondensables in the system will cause...






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






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






25. 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






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






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






28. An air conditioning system using a fixed-orifice metering device and with noncondensables in the system will cause...






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






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






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






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






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






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






35. What type of problems can be caused by an oversized air conditioning system...






36. 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






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






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






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






40. 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






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






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






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






44. 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






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






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






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






48. 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






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






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