How is the heating surface of a boiler calculated?

The calculation of the heating surface of a boiler is essential for determining its efficiency and capacity. The formula involves the diameter (D), the length (L), and the number of tubes (N) in the boiler. The surface area is derived from the formula for the surface area of a cylinder (which is 2πrL) adjusted for the specific context of the boiler's configuration.

Choosing the option that incorporates division by 144 correctly accounts for the conversion of the area from square inches to square feet, which is a common unit change in heating surface calculations. There are 144 square inches in one square foot (12 inches x 12 inches), hence using this factor is necessary when calculating the heating surface area in square feet.

This method ensures that the calculated heating surface can be accurately compared against boiler ratings, maintenance requirements, and efficiency assessments, allowing operators to make informed decisions regarding the boiler’s performance and adjustments as needed.