What might be an indicator of a high-pressure hot water system?

A water temperature exceeding 250°F is indeed a strong indicator of a high-pressure hot water system. In such systems, water is heated under pressure, allowing it to reach temperatures above the normal boiling point of water, which is 212°F at atmospheric pressure. When the pressure is maintained at high levels, it raises the boiling point, enabling the system to operate efficiently at elevated temperatures.

In this context, high-pressure hot water systems are designed to work effectively at these higher temperatures for various applications including heating and industrial processes. The design ensures that the system remains safe and functional while operating at these extreme conditions.

Other indicators like excessive steam consumption or rapid water circulation could suggest issues rather than being clear indicators of the system's operational parameters. Meanwhile, a pressure exceeding 50 psi could indicate high pressure, but it is not exclusive to just hot water systems and could also occur in other types of systems.