Water cooled or evaporative NH3 systems should be tested at what pressure?

Water cooled or evaporative ammonia (NH3) systems should be tested at 250 psi because this pressure aligns with industry standards for safe testing of pressure vessels and piping systems transporting ammonia. These standards are designed to ensure the integrity of the system under conditions that exceed normal operational pressures.

Testing at this pressure helps to identify any potential leaks or weaknesses in the system before it goes live. The 250 psi testing requirement strikes a balance between providing sufficient pressure for a thorough examination without unnecessarily risking damage to the system components that could occur at higher pressures. This practice is crucial for maintaining safety and preventing hazardous leaks of ammonia, which can be dangerous.

Higher testing pressures may not be necessary and could impose additional strain on the materials, leading to potential failures during testing. Therefore, the selection of 250 psi as the testing pressure is grounded in both safety protocols and the engineering properties of the materials used in ammonia piping systems.