For boilers larger than 100 ft², what is the minimum feed water line size?

For boilers larger than 100 ft², what is the minimum feed water line size?

• A. 1/2 inch
• B. 3/4 inch
• C. 1 inch
• D. 1 1/2 inch

Answer: (B)

When a boiler’s size and steam output increase, the amount of water that must be supplied to replace what’s lost as steam goes up as well. That means the feed water line has to deliver water quickly enough to keep the boiler from dropping the water level during operation. For boilers larger than 100 ft², the minimum feed water line size is 3/4 inch because this size provides enough flow to meet the higher makeup demands without causing excessive pressure loss in the line. A 1/2 inch line would typically be too small to keep up with the increased demand, while 1 inch or larger lines are reserved for even larger systems with even greater water needs. The 3/4 inch size strikes a practical balance, ensuring reliable water feed and stable boiler operation under typical loads.

When a boiler’s size and steam output increase, the amount of water that must be supplied to replace what’s lost as steam goes up as well. That means the feed water line has to deliver water quickly enough to keep the boiler from dropping the water level during operation. For boilers larger than 100 ft², the minimum feed water line size is 3/4 inch because this size provides enough flow to meet the higher makeup demands without causing excessive pressure loss in the line. A 1/2 inch line would typically be too small to keep up with the increased demand, while 1 inch or larger lines are reserved for even larger systems with even greater water needs. The 3/4 inch size strikes a practical balance, ensuring reliable water feed and stable boiler operation under typical loads.