A cast iron boiler is classified as which type of boiler?

A cast iron boiler is typically classified as an HRT (Horizontal Return Tubular) boiler. This type of boiler is characterized by its design, which includes horizontal tubes that return to the front of the boiler after passing through the combustion chamber.

The construction of cast iron boilers allows for high durability and excellent heat transfer. In addition, their ability to withstand thermal cycling makes them a preferred choice for residential heating applications, as they can effectively handle the stresses of heating and cooling.

While fire-tube and water-tube boilers are common classifications for other boiler types, they operate on different principles and are constructed differently. Fire-tube boilers feature tubes through which hot gases pass, while water-tube boilers have water-filled tubes surrounded by combustion gases. Vertical boilers, on the other hand, are typically designed for compact spaces and do not conform to the cast iron design specifications.

Therefore, recognizing a cast iron boiler as an HRT type aligns with its construction and operational characteristics.