What is required to hold the temperature pressure relief valve open during testing?

In order to properly test a temperature-pressure relief valve, it is essential to hold it open for a sufficient duration to ensure that it functions as intended. Holding the valve open for a minimum of 5 to 10 seconds allows for the escape of water and the assessment of whether the valve will close again properly once released. This timeframe is adequate to verify that the valve is not only operational but also able to protect against excessive temperature or pressure, which is crucial for the safety of the system.

Testing for a duration shorter than 5 seconds may not provide enough time to observe a reliable opening and closing action of the valve. Similarly, holding it open for periods like 30 seconds or until the tank is empty could lead to unnecessary risks, such as draining the system completely or causing damage due to prolonged exposure to an open state. Thus, the requirement of holding the valve open for a minimum of 5 to 10 seconds is both a standard and practical measure for appropriate testing and evaluation.