Walmart Maintenance Test Question and Answers 2 — Questions and Answers
Question 1: What is the recommended air filter replacement frequency for a commercial rooftop HVAC unit in a retail environment?
- Once a year
- Every 30-90 days depending on conditions (Correct answer)
- Only when the unit stops working
- Every 5 years with the unit replacement
Correct answer: Every 30-90 days depending on conditions
Commercial HVAC filters in high-traffic retail environments should be checked monthly and replaced every 30-90 days.
High-traffic retail environments generate significant airborne particulates from foot traffic, loading dock activity, and merchandise handling. Filters clog faster than in office settings. Clogged filters restrict airflow, reducing efficiency by up to 15%, increasing energy costs, and straining the compressor. A 30-90 day schedule balances air quality, energy efficiency, and component protection.
Question 2: When using a multimeter to check for voltage in a 120V outlet, between which points should you place the probes?
- Both probes in the hot slot
- Hot (narrow slot) and neutral (wide slot) or hot and ground (Correct answer)
- Both probes in the ground hole
- Neutral and ground only
Correct answer: Hot (narrow slot) and neutral (wide slot) or hot and ground
Voltage is measured between the hot conductor and either neutral or ground to read the potential difference.
A standard 120V outlet has three connections: hot (narrow slot), neutral (wide slot), and ground (round hole). To measure voltage, place one probe on the hot terminal and the other on neutral or ground. Hot to neutral should read approximately 120V. Hot to ground should also read approximately 120V. Neutral to ground should read near 0V. Any significant deviation indicates a wiring problem.
Question 3: A belt-driven exhaust fan is making a squealing noise. What is the most probable cause?
- The fan blades are bent
- The belt is loose, worn, or glazed (Correct answer)
- The exhaust ductwork is clogged
- The motor is running backwards
Correct answer: The belt is loose, worn, or glazed
Squealing from belt-driven equipment typically indicates a loose, worn, or glazed belt that is slipping on the pulleys.
Belt squeal occurs when the belt slips on the pulleys rather than gripping and turning them efficiently. Causes include: insufficient tension (belts stretch over time), glazed belt surface from age and heat, worn belt edges that no longer seat properly in the pulley groove, or pulley misalignment. Replacing the belt and checking pulley alignment resolves the issue. Belt tension should allow approximately 1 inch of deflection per foot of span.
Question 4: What is the purpose of a backflow preventer in a commercial plumbing system?
- To increase water pressure
- To prevent contaminated water from flowing back into the potable water supply (Correct answer)
- To reduce water usage
- To heat water more efficiently
Correct answer: To prevent contaminated water from flowing back into the potable water supply
Backflow preventers protect the public water supply from contamination caused by pressure changes in the plumbing system.
Backflow occurs when negative pressure (backsiphonage) or higher downstream pressure (backpressure) reverses water flow, potentially pulling contaminated water into the clean supply. Commercial facilities with chemical cleaning systems, irrigation connections, or boiler fill lines are particularly at risk. Backflow preventers use check valves and relief ports to stop reverse flow. Annual testing is typically required by local health codes.
Question 5: During a routine inspection, you notice corrosion on the battery terminals of an emergency generator. What should you do?
- Replace the entire generator
- Clean the terminals with a baking soda solution, apply anti-corrosion compound, and tighten connections (Correct answer)
- Ignore it since the generator only runs during emergencies
- Pour water on the terminals to rinse them
Correct answer: Clean the terminals with a baking soda solution, apply anti-corrosion compound, and tighten connections
Battery terminal corrosion increases resistance, which can prevent the generator from starting when needed. Cleaning and protecting the terminals is routine maintenance.
Battery terminal corrosion (typically white or greenish buildup) is caused by acid fumes reacting with the lead and copper terminals. It increases electrical resistance, potentially preventing the generator from starting during an emergency. The proper remedy is disconnecting the cables (negative first), cleaning with a baking soda/water solution and wire brush, applying anti-corrosion spray or dielectric grease, and retightening connections. This should be part of the weekly generator inspection routine.
Question 6: What does the acronym PPM stand for in the context of maintenance scheduling?
- Parts Per Million
- Planned Preventive Maintenance (Correct answer)
- Personal Protection Methods
- Power Plant Management
Correct answer: Planned Preventive Maintenance
PPM stands for Planned Preventive Maintenance, a scheduled approach to maintaining equipment before failures occur.
Planned Preventive Maintenance (PPM) is a systematic approach where maintenance tasks are scheduled at regular intervals based on time, usage, or condition. PPM reduces unexpected breakdowns, extends equipment life, and lowers total maintenance costs. A typical retail facility PPM program covers HVAC, refrigeration, electrical, plumbing, fire systems, and building envelope on daily, weekly, monthly, quarterly, and annual schedules.
Walmart Maintenance Test Question and Answers 2
What is the recommended air filter replacement frequency for a commercial rooftop HVAC unit in a retail environment?