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






2. 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






3. 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






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






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






6. 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






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






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 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






10. 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...






11. 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






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






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






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






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 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






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






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






19. 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






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






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






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






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






25. Insufficient airflow can be caused by...






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






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






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






29. Air filters should be replaced...






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






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






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






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






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






35. 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






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






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






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






39. 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






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






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






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






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






44. 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






45. 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






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






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






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






49. 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






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