MACS Certification Questions And
Answers With Verified Solutions 100%
Correct Latest Update.
If the mechanic's gauges rise from a vacuum to pressure, what is required? -
ANSWER Additional recovery
What is the only way to fully clear moisture from the A/C system? - ANSWER
Replacing the desiccant
Pressure ______ the boiling point - ANSWER Raises
Vacuum _______ the boiling point - ANSWER Lowers
What should you do when replacing hoses? - ANSWER Make sure you
have the correct type/size of tubing
What does GWP stand for? - ANSWER Global Warming Potential
CO2 is equal to what A/C system? - ANSWER R-744
HFO-1234yf systems are acceptable in what kinds of vehicles? - ANSWER
Passenger cars, light-duty trucks, medium-duty passenger vehicles, heavy-duty
pickup trucks, and complete heavy-duty vans
HFO-1234yf systems are not acceptable in what kinds of vehicles? - ANSWER
Heavy-duty trucks, refrigerated transport, and off-road vehicles such as farm
equipment
HFO-1234yf is classified by ASHRAE as what? - ANSWER A2L- mildly
flammable
R-744 systems operate at ___ to ___ times higher than HFC-134a and HFC-152a
systems. - ANSWER 5 to 10
HFC-152a is ___ - ANSWER flammable
What are the 2 types of HFC-152a systems? - ANSWER Direct expansion
and secondary loop type
Direct Expansion - ANSWER Refrigerant directly expands within the
evaporator that is located inside the passenger compartment
Secondary Loop (Open Loop) - ANSWER A circulating non-flammable
fluid replaces the evaporator which provides isolation between the flammable
refrigerant and the passenger compartment
Section 609 of the Clean Air Act gives the EPA authority to do what? -
ANSWER Establish standards and requirements regarding the servicing of
mobile A/C systems
Answers With Verified Solutions 100%
Correct Latest Update.
If the mechanic's gauges rise from a vacuum to pressure, what is required? -
ANSWER Additional recovery
What is the only way to fully clear moisture from the A/C system? - ANSWER
Replacing the desiccant
Pressure ______ the boiling point - ANSWER Raises
Vacuum _______ the boiling point - ANSWER Lowers
What should you do when replacing hoses? - ANSWER Make sure you
have the correct type/size of tubing
What does GWP stand for? - ANSWER Global Warming Potential
CO2 is equal to what A/C system? - ANSWER R-744
HFO-1234yf systems are acceptable in what kinds of vehicles? - ANSWER
Passenger cars, light-duty trucks, medium-duty passenger vehicles, heavy-duty
pickup trucks, and complete heavy-duty vans
HFO-1234yf systems are not acceptable in what kinds of vehicles? - ANSWER
Heavy-duty trucks, refrigerated transport, and off-road vehicles such as farm
equipment
HFO-1234yf is classified by ASHRAE as what? - ANSWER A2L- mildly
flammable
R-744 systems operate at ___ to ___ times higher than HFC-134a and HFC-152a
systems. - ANSWER 5 to 10
HFC-152a is ___ - ANSWER flammable
What are the 2 types of HFC-152a systems? - ANSWER Direct expansion
and secondary loop type
Direct Expansion - ANSWER Refrigerant directly expands within the
evaporator that is located inside the passenger compartment
Secondary Loop (Open Loop) - ANSWER A circulating non-flammable
fluid replaces the evaporator which provides isolation between the flammable
refrigerant and the passenger compartment
Section 609 of the Clean Air Act gives the EPA authority to do what? -
ANSWER Establish standards and requirements regarding the servicing of
mobile A/C systems
