On a water heater, which device helps prevent overheating and scalding by releasing pressure?

• A. Relief valve
• B. Shutoff valve
• C. Isolation valve
• D. Check valve

Answer: (A)

The key safety device on a water heater that prevents overheating and scalding by releasing pressure is the relief valve, often called the temperature/pressure relief valve. This valve automatically opens whenever the water temperature or system pressure gets too high, venting hot water or steam to bring the pressure down and prevent the tank from failing or scalding someone.

This is the best answer because other valves have different roles: the shutoff valve stops the water flow into the heater, the isolation valve separates the heater from the system for service, and the check valve prevents backflow. None of these are designed to release pressure in response to overheating.

Regularly test the relief valve and ensure the discharge path is clear and directed to a safe area; replace the valve if it doesn’t operate or if it leaks continuously.