Gas Fitter Test 2025 – 400 Free Practice Questions to Pass the Exam

The maximum termination height for the discharge piping from the temperature and pressure relief valve (TPR) on a water heater is set at 12 inches from the floor. This requirement is established to ensure that any discharge from the TPR valve is safely directed away from the water heater and does not pose a hazard to individuals in the vicinity.

By keeping the discharge piping at or below 12 inches, it prevents potential scalding from hot water that may escape during a relief operation, as the piping will direct the discharge toward the ground. This distance is also manageable for visual inspection and maintenance. Ensuring compliance with this maximum height is critical for safe operation and adheres to plumbing codes designed to protect both property and individuals.

When considering other heights, such as 3, 6, or 18 inches, these do not provide the appropriate balance of safety and compliance outlined in plumbing regulations. Therefore, the specification of 12 inches strikes an essential balance in ensuring safety while maintaining operational effectiveness of the water heater's safety features.