In what terms is the capacity of a heating boiler usually expressed?

• A. Pounds of pressure
• B. Square feet of radiation
• C. Cubic feet of gas
• D. Liters of water

Answer: (B)

The capacity of a heating boiler is usually expressed in terms of square feet of radiation. This measurement is crucial as it indicates the surface area available for heat transfer from the boiler to the surrounding space, which directly impacts the efficiency and effectiveness of heating.

In heating systems, the square footage of radiation correlates to the amount of heat a boiler can provide, allowing for the proper sizing of the boiler relative to the area that needs to be heated. This is particularly important when designing heating systems for buildings, as it ensures that the boiler can meet the heating demands based on the area of the space being heated.

While pounds of pressure relates to the boiler's operating pressure, and cubic feet of gas or liters of water refer to fuel consumption or water capacity, they do not directly convey the heating capacity of the boiler in relation to the space it serves. Thus, using square feet of radiation remains the standard and most relevant measure for a boiler's heating capacity.