M13 Chapter 12 Retrofit and Future Trends AUTI 142
All of the following statements about thermostatic expansion vales on retrofitted systems are true, EXCEPT: Group of answer choices The expansion valve does not have to be replaced when retrofitting a system from R-12 to R-134a. If a defective expansion valve is replaced, always use a model designed for the system refrigerant. A R-12 expansion valve used in an R-134a system will result in higher superheat and reduced evaporator efficiency. An R-134a valve used in a R-12 system will have reduced superheat.
A R-12 expansion valve used in an R-134a system will result in higher superheat and reduced evaporator efficiency.
Technician A says that the shop that performed the A/C system retrofit must be identified on the retrofit label. Technician B says that the new refrigerant installed must be identified on the retrofit label. Who is correct? Group of answer choices Technician A only Technician B only Both A and B Neither A nor B
Both A and B
Vacuum measurement is being discussed. Technician A says the best method is to use an electronic thermistor vacuum gauge. Technician B says a thermistor may use an analog gauge to display vacuum readings. Who is correct? Group of answer choices Technician A only Technician B only Both A and B Neither A nor B
Both A and B
Which of the following desiccants should be used with HFC-134a refrigerant? Group of answer choices XH5 XH7 XH9 Both B and C
Both B and C
Three refrigerants are currently approved by the EPA for automotive use to replace R-12. Group of answer choices True False
False
All of the following statements about system evacuation are true, EXCEPT: Group of answer choices All systems should be evacuated for a minimum of 30 minutes. Vacuum should reach at least 24 to 26 inHg (20.3 to 23.5 kPa absolute) in the first 15 minutes. If vacuum does not reach 24 to 26 inHg (20.3 to 23.5 kPa absolute), evacuate for a longer time. The longer the evacuation period, the better the moisture removal.
If vacuum does not reach 24 to 26 inHg (20.3 to 23.5 kPa absolute), evacuate for a longer time.
Technician A says flushing the air conditioning before retrofitting is a common procedure. Technician B says each component should be removed and flushed individually. Who is correct? Group of answer choices Technician A only Technician B only Both A and B Neither A nor B
Neither A nor B
The Clean Air Act of 1990 says after July 1, 1992, which of the following refrigerants may be intentionally vented? Group of answer choices R-12 R-134a R-22 None of the above
None of the above
Evacuation of an air conditioning system is being discussed. Technician A says one factor affecting the speed of evacuation is internal restrictions. Technician B says all of the oil is usually removed during evacuation. Who is correct? Group of answer choices Technician A only Technician B only Both A and B Neither A nor B
Technician A only
Technician A says after the retrofit is complete, a function test should be made. Technician B says system pressures and temperatures for HFC-134a should be the same as for CFC-12. Who is correct? Group of answer choices Technician A only Technician B only Both A and B Neither A nor B
Technician A only
A refrigerant retro fit label must contain all of the following, Except: Group of answer choices The refrigerant charge amount installed. The amount of R-12 removed from the system. The type of refrigerant oil installed and the part number. Name and address of the installer who performed the retrofit.
The amount of R-12 removed from the system.
A modification that updates or upgrades a system or device is called a retrofit. Group of answer choices True False
True
A purity test should be held any time there is a concern about the quality of the refrigerant in the system. Group of answer choices True False
True
The air conditioning system is purged of refrigerant if the manifold gauges show a vacuum. Group of answer choices True False
True
To drain oil from a component, the component must be removed from the vehicle. Group of answer choices True False
True
