G2 Gas Fitter Practice Exam

What components are typically found in a standard under-fired storage water heater?

1. Blower, expansion tank, and thermostat

2. Temperature and pressure relief valve, anode, and mixing valve

3. Heating element, insulation, and drain valve

4. Sensors, pump, and control panel

The correct answer is: Temperature and pressure relief valve, anode, and mixing valve

A standard under-fired storage water heater generally includes a temperature and pressure relief valve, an anode, and a mixing valve, all of which play crucial roles in its operation and safety. The temperature and pressure relief valve is vital for safety, as it prevents excessive pressure build-up within the tank. It automatically releases water if the temperature or pressure exceeds safe levels, thus protecting the tank and preventing potential explosions or leaks. The anode rod is an essential component for prolonging the life of the water heater. It helps to prevent tank corrosion by attracting corrosive elements in the water to itself, thus sacrificing itself over time. This sacrificial action significantly extends the lifespan of the tank. The mixing valve is important for maintaining a safe and comfortable water temperature throughout the system. It helps to blend hot water from the heater with cold water to ensure that the water delivered to the fixtures is at a desired and safe temperature, preventing scalding accidents. These components are integral to the functioning and safety of under-fired storage water heaters, making this choice the most accurate representation of what is typically found in such units.