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. 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






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






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






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






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






6. 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






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






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






9. Insufficient airflow can be caused by...






10. 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






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






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






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






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






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






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






17. What is the purpose of the TXV...






18. 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






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






20. A system that uses a thermal electric expansion valve...






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






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






23. 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






24. A commercial customer calls on a 90






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






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






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






28. 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






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






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






31. 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...






32. 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






33. 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






34. 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






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






36. 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






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






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






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






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






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






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






43. 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






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






45. 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






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






47. Air filters should be replaced...






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






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






50. 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...