New York Low Pressure Boiler COF Practice

What is the relief capacity percentage for a low pressure boiler under 30 psig?

1. 10% above

2. 20% above

3. 30% above

4. No relief capacity

The correct answer is: 20% above

For low pressure boilers operating under 30 psig, the relief capacity is critical to ensure safety and prevent over-pressurization. The code typically requires that the safety relief valve be designed to handle excess pressure by venting steam or water as needed. A relief capacity of 20% above the maximum allowable working pressure is standard practice because it provides an adequate buffer to manage unexpected surges or fluctuations in pressure. This safety measure is essential in maintaining system integrity and preventing potential hazards associated with pressure build-up. Other percentages may not provide the same level of safety margin; too low a percentage could lead to unsafe pressure levels, while a recovery beyond necessary limits could result in inefficiencies or unnecessary wear on the equipment. Thus, the requirement of a 20% relief capacity ensures both safety and operational reliability for low pressure boilers.