Florida InterNACHI State Practice Exam

The purpose of a TPR (Temperature and Pressure Relief) valve in a water heating system is to release excess pressure. This safety device is essential for preventing dangerous situations that could arise from excessive pressure or temperature within the water heater.

When water is heated, it expands and can create increased pressure inside the tank. If the pressure exceeds a certain threshold, the TPR valve opens, allowing hot water or steam to escape, thus relieving stress on the tank and preventing potential rupture or explosion. By functioning in this manner, the TPR valve plays a vital role in ensuring the safety and integrity of the water heating system.

Regulating temperature alone or increasing pressure would not serve a protective function and could lead to hazardous conditions. Similarly, filtering water is unrelated to the operation of a TPR valve, as this valve has no role in the purification or filtration of water.