Final answer:
The installation of a temperature pressure relief valve on a water heater must be within the top 8-inches of the tank to function properly, making option A the correct answer. Installing it above the tank in the pipe can lead to malfunction and safety hazards.
Step-by-step explanation:
The question pertains to the installation of a temperature pressure relief valve on a water heater, which is a safety device designed to release water if either the temperature or pressure inside the tank becomes too high.
According to standard safety guidelines and regulations, such as those set by the American Society of Mechanical Engineers (ASME), a temperature pressure relief valve must be installed in a very specific location on the water heater to function properly. Installing the valve above the tank in the pipe is incorrect.
The correct installation for a temperature pressure relief valve is option a, which states it must be installed within the top 8-inches of the tank. This placement ensures that the valve can accurately detect the temperature and pressure within the tank.
If the valve is installed too high, or in an incorrect position like in the pipe above the tank, it might not sense the true temperature and pressure within the water heater, which could lead to a failure to release pressure and prevent potential hazards such as a tank explosion.
Therefore, the correct option in the final answer is option A: Must be installed within the top 8-inches of the tank.