MACS 609 Q&A 100% Correct

Which type of tank must be used during the transfer of refrigerant? - ANSWER Question 10 options: Tanks marked DOT 4BA When it has been determined that an A/C system has a low refrigerant charge, what should be done? - ANSWER Perform a leak detection procedure One effect of some refrigerant gases in the atmosphere is that they: - ANSWER Contribute to trapping heat Mixing CFC-12 and HFC-134a in the same system will: - ANSWER Result in refrigerant cross contamination How much moisture is removed from a mobile A/C system during a typical evacuation? - ANSWER Possibly none Paid technicians who service or repair mobile A/C systems using HFC-22 as refrigerant, or service cargo refrigeration equipment: - ANSWER Must be Section 608 Type II certified HFO-1234yf is classified as "A2L-mildly flammable." This means: - ANSWER It can ignite under certain circumstances Section 609 of the Clean Air Act requires that recovery/recycling equipment: - ANSWER Must be registered with the EPA What is the advantage of using refrigerant identification equipment? - ANSWER Allows the ability to determine what type of refrigerant is in system When performing engine pre-heat for refrigerant removal, the technician should do ALL of the following EXCEPT: - ANSWER Make sure the compressor is operating If a large amount of lubricant is removed from a system during refrigerant recovery: - ANSWER The system likely contained too much lubricant PAG lubricant: - ANSWER Is hygroscopic (absorbs moisture) If lubricant is removed by recovery equipment during system refrigerant removal, what must be done with the lubricant? - ANSWER Re-install lubricant removed by the recovery equipment Before reuse, what must be done with HFC-134a that has been recovered from a mobile A/C system using recovery-only equipment? - ANSWER Question 2 options: Recycle the HFC-134a before reuse using certified equipment When can HFC-134a become combustible in a mobile air conditioning system? - ANSWER If shop air is used in the system in an attempt to check for leaks and HFC-134a is present Which type of mobile A/C system will usually require additional time / precautions to extract all the refrigerant? - ANSWER Accumulator type Electronic leak detectors certified to SAE J2791 have the capacity of identifying leakage rates as low as: - ANSWER 0.15 ounces per year When recovery/recycling equipment is used to remove refrigerant from a mobile A/C system, how much lubricant will be removed during the operation? - ANSWER Generally, very little, if any Why is it necessary to insure that service port caps containing good seals are installed? - ANSWER To minimize refrigerant loss Which of the following statements is correct about flushing A/C systems? - ANSWER Flushing solvents may remain in A/C systems, causing problems When using an HFC-134a refrigerant recovery machine, after competing the first recovery process, how long must you wait, then check the machine's gauges for a rise in pressure above vacuum, which would indicate that the system still contains some refrigerant? - ANSWER 5 minutes Specific safety information for managing incidents involving refrigerants and other chemicals (inhalation, spills, fires, etc) is found in the: - ANSWER Material safety data sheet (MSDS) for the chemical What is not identified in the manual as a concern with field-coupled hoses? - ANSWER Length of hose Which of the following is NOT a factor in how much refrigerant can be recovered from an A/C system? - ANSWER The age of the vehicle HFO-1234yf can be used in: - ANSWER Any light vehicle with an air conditioning system designed to use it The use of ultraviolet (UV) or fluorescent dyes in an HFO-1234yf system is: - ANSWER Approved by some vehicle manufactures but not by others One effect of some refrigerant gases in the atmosphere is that they: - ANSWER Contribute to trapping heat Which item is not mentioned in the SAE J2099 Standard of refrigerant purity? - ANSWER Sludge When it has been determined that an A/C system has a low refrigerant charge, what should be done? - ANSWER Perform a leak test procedure Which item is not mentioned in the SAE J1991 standard of refrigerant purity? - ANSWER Acid Which of the following is unlikely to affect refrigerant charge accuracy? - ANSWER A/C Compressor CFC-12 recovery equipment has SAE 3/8-inch service fittings. HFC-134a recovery equipment has: - ANSWER Quick-couple design