New York Low Pressure Boiler COF Practice

How do you protect potable feed water for a boiler?

1. Pressure vacuum breaker

2. Backflow preventer

3. Strainer

4. Water softener

The correct answer is: Pressure vacuum breaker

To protect potable feed water for a boiler, utilizing a pressure vacuum breaker is essential in preventing contamination of the drinking water supply. Its design allows for the protection against back-siphonage, which can occur when there is a sudden drop in supply pressure, potentially allowing non-potable water to flow back into the potable system. This is particularly important in boiler systems where the possibility of cross-connections exists. In scenarios involving back-siphonage, a vacuum could form that pulls water from the lower pressure side into the higher pressure side, hence contaminating the clean feed water. The pressure vacuum breaker operates by allowing air into the system when pressure drops, thus breaking the siphon and preventing backflow. This effectively safeguards the potable supply and ensures compliance with health and safety regulations. While a backflow preventer also serves a similar function, a pressure vacuum breaker is specifically designed to address issues related to pressure changes, making it a more specialized choice for this scenario. Other options like a strainer or water softener primarily serve different purposes, such as removing particulates or treating water hardness, respectively, and do not contribute directly to protecting the potable water supply from contamination.