diesel mechanics A/C practice quiz

The recovery process on an R-12 or R-134a A/C system should continue until a stable vacuum is held by the system for:

• 1 min

• 2 min

• 4 min

• 5 min

A recycled refrigerant container has been checked and found to be above the given pressure limit for the ambient temperature.

Tech A says that the refrigerant container should be placed in a cooler storage area before use.

Tech B says that the vapor in the container should be slowly vented into a refrigerant handling unit.

Who is right?

• Tech A only

• Tech B only

• Both A and B

• Neither A nor B

The ozone layer filters out most of the sun's harmful:

• Infared radiation

• ultraviolet radiation

• gamma radiation

• alpha radiation

The reduction of ozone in the stratosphere could cause:

• an increase in skin cancer and eye cataracts

• an increase in plant life growth

• an increase in the earth's polar ice

• an increase in marine life growth

Tech A says that sunlight striking CFC molecules can cause chlorine to be released

Tech B says that chlorine atoms react with ozone to produce chlorine monoxide

Who is Right?

• Tech A only

• Tech B only

• Both A and B

• Neither A nor B

R-134a refrigerant must be reclaimed to meet which of these purity standards?

• J2788

• DOT-4BA

• J2099

• AHRI

If the required charge level of refrigerant for an MVAC system is 40 ounces, which of these is the correct charge level measure in pounds?

• 1.75 lb (794 g)

• 2.50 lb (1.13 kg)

• 3.75 lb (1.70 kg)

• 4.50 lb (2.04 kg)

Tech A says that recovery/recycling/recharging equipment for R-1234yf refrigerant requires integration with a refrigerant identifier

Tech B says that recovery/recycling/recharging equipment for R-1234yf refrigerant uses a 17mm O.D. quick coupler on the low-side service hose

Who is right

• Tech A only

• Tech B only

• Both A and B

• Neither A nor B

Which of these identifies a cylinder of R-1234yf refrigerant?

• White

• Gray

• light blue

• White with a red band

A container of recycled R-134a refrigerant that is being tested for non-condensable gasses (air) should be:

• chilled to 45° (7°C)

• stored out of direct sunlight

• heated to 95°f (35°C)

• stored for less than 6 hours