CAR Tools & Equipment Operation 3 — Questions and Answers
Question 1: What is the correct method for purging a refrigerant recovery hose of air before connecting to an appliance system?
- Blow air through the hose with your mouth
- Crack the recovery cylinder valve briefly to purge with refrigerant vapor (Correct answer)
- Use compressed shop air to blow through the line
- No purging is needed for short hoses
Correct answer: Crack the recovery cylinder valve briefly to purge with refrigerant vapor
Briefly cracking the recovery cylinder valve allows refrigerant vapor to purge air from the hose, preventing non-condensable gases from contaminating recovered refrigerant.
Question 2: Which hand tool is used to identify and sort different metals in mixed appliance scrap before shredding?
- Multimeter
- Thermocouple probe
- Magnet and XRF analyzer (Correct answer)
- Oscilloscope
Correct answer: Magnet and XRF analyzer
A magnet quickly separates ferrous from non-ferrous metals, while an XRF (X-ray fluorescence) analyzer identifies specific alloy compositions for accurate sorting.
Question 3: A pneumatic impact wrench fails to develop full torque during appliance disassembly. What should the technician check first?
- The socket size being used
- The air supply pressure and hose diameter (Correct answer)
- The oil level in the compressor tank
- The age of the impact wrench
Correct answer: The air supply pressure and hose diameter
Insufficient air supply pressure or a hose that is too narrow restricts airflow and is the most common cause of reduced impact wrench performance.
Question 4: When using a forklift to move stacked appliances in a recycling facility, loads should be transported with the forks in what position?
- Raised 12–18 inches above the ground for visibility
- Tilted fully forward for stability
- Lowered 4–6 inches off the ground with mast tilted back (Correct answer)
- At mid-height with forks level
Correct answer: Lowered 4–6 inches off the ground with mast tilted back
Traveling with loads low (4–6 inches) and the mast tilted back lowers the center of gravity and prevents tipping during transit.
Question 5: Which tool is used to safely discharge a capacitor in a microwave oven before disassembly for recycling?
- Standard flathead screwdriver
- Insulated discharge resistor tool or screwdriver with discharge resistor (Correct answer)
- Rubber-handled pliers
- Capacitor meter probe
Correct answer: Insulated discharge resistor tool or screwdriver with discharge resistor
A discharge resistor tool safely dissipates stored charge across the capacitor terminals, preventing dangerous arc-flash when touching internal components.
Question 6: What is the recommended practice when an angle grinder wheel becomes cracked during appliance dismantling operations?
- Continue use at reduced speed until the job is complete
- Tape the crack and reduce grinding pressure
- Remove and replace the wheel immediately (Correct answer)
- Inspect the crack size; replace only if larger than 1 inch
Correct answer: Remove and replace the wheel immediately
Any crack in a grinding wheel creates a risk of catastrophic wheel burst; the wheel must be removed and replaced immediately regardless of crack size.
Question 7: In appliance recycling, a conveyor belt used to transport scrap metal begins to track (drift) to one side. What is the first corrective step?
- Increase belt tension on the drifting side
- Adjust the tail pulley to correct belt tracking (Correct answer)
- Add weight to the opposite side of the belt
- Reduce conveyor speed until the belt centers itself
Correct answer: Adjust the tail pulley to correct belt tracking
Adjusting the tail (or take-up) pulley alignment is the standard first step to correct belt tracking drift on a conveyor system.
CAR Tools & Equipment Operation 3
What is the correct method for purging a refrigerant recovery hose of air before connecting to an appliance system?