Maine Oil Practice Exam 2026 - Free Oil Practice Questions and Study Guide

Hot water relief valves are crucial components in hot water heating systems, designed primarily to prevent excessive pressure build-up that could lead to dangerous situations, such as tank rupture or explosion. The typical setting for these valves is usually around 150 psi. This pressure point provides a balance between ensuring safety and allowing the system to operate effectively under normal conditions.

When the pressure in the system exceeds 150 psi, the relief valve opens to release excess pressure, thus safeguarding the entire installation from damage. This standard is common across many heating systems, ensuring uniformity and reliability in boiler and water heater applications.

While other pressure values like 100 psi, 200 psi, or 250 psi might seem plausible, they are generally less common for standard residential hot water applications. Using a relief valve set at 150 psi is a widely accepted practice to maintain safety and efficiency in hot water systems.