WALMART MAINTENANCE HVAC and Refrigeration 2

Question 1

What is a thermostat's role in an HVAC system?

Accepted Answer

To sense temperature and signal the HVAC system to turn on or off to maintain the setpoint

Answer

A thermostat acts as the control interface, measuring ambient temperature and sending signals to activate heating or cooling systems to maintain the desired temperature.

Question 2

What is the purpose of preventive maintenance on rooftop HVAC units?

Accepted Answer

To extend equipment life, maintain efficiency, and prevent costly breakdowns

Answer

Regular preventive maintenance keeps HVAC units running efficiently, extends their lifespan, prevents unexpected breakdowns during extreme weather, and reduces energy costs.

Question 3

Why is proper airflow important in a walk-in cooler?

Accepted Answer

To ensure even temperature distribution and prevent hot spots that could cause food spoilage

Answer

Proper airflow ensures uniform temperature throughout the cooler. Hot spots from blocked airflow can cause food to spoil even if the thermostat reads the correct temperature.

Question 4

What is a Building Management System (BMS) used for?

Accepted Answer

Centrally monitoring and controlling HVAC, lighting, and other building systems

Answer

A BMS integrates control of HVAC, lighting, and other systems into a centralized platform for monitoring, scheduling, and optimizing building operations.

Question 5

What causes ice to form on evaporator coils in a refrigeration system?

Accepted Answer

Restricted airflow, low refrigerant charge, or defrost system failure

Answer

Ice formation on evaporator coils typically indicates restricted airflow from dirty filters/coils, low refrigerant causing coil temperature to drop below freezing, or a malfunctioning defrost system.

WALMART MAINTENANCE Practice Test

WALMART MAINTENANCE Practice Test

WALMART MAINTENANCE HVAC and Refrigeration 2