Which faucet drains water from the bottom of a water heater?

• A. Boiler Drain
• B. Stop Valve
• C. Isolation Valve
• D. Ball Valve

Answer: (A)

A drain at the bottom of a water heater is provided specifically to empty the tank for maintenance, such as flushing out sediment. This bottom valve, called a boiler drain, is designed to be opened to let water out of the entire tank and usually has a hose connection so the discharged water can be directed to a drain or outside.

The other options are general shutoff or isolation valves used to stop or isolate flow in lines, not to drain the tank itself. They aren’t intended for draining the entire heater from the bottom, so the bottom boiler drain is the correct choice for this purpose.