The actual process of a commercial boiler is relatively simple: a heat source warms up water in a chamber and pushes it out into a commercial building where the hot water or steam provides sensible heat as it passes through radiators and other heat exchangers. But to explain how commercial boilers work, you must understand the various ways this is accomplished in modern systems.

​Commercial Boilers: A Quick Explanation

​A boiler includes a combustion chamber with a burner, a heat exchanger, and a chamber for the water. The heat exchanger can be produced using a variety of materials, including cast iron, carbon steel, stainless steel, or copper, all while keeping the water from coming into direct contact with the flame source.​However, the system still needs several more components in order to operate safely, including:

1. Controls: However complex the method can be, there must be a way to control the amount of water that enters the boiler, when the burners light (and, in some applications, how many of them light), along with myriad other factors.
2. Exhaust system: The majority of boiler systems are located deep within a building and the combustion process naturally produces the products of combustion (carbon dioxide and other emissions). For safety, these must be vented to the outside.

​Types of Commercial Boilers

​There are myriad types of commercial boilers, which is one reason the explanation above is so brief. They vary drastically in size and are powered by either natural gas, fuel oil, biofuels, or electricity. You could also group commercial boilers based on whether the boiler system produces hot water or steam.​To stick to the basics of a commercial boiler, however, you should focus on how the water in the system is heated by the combustion itself. In this case, there are two primary types of boiler:

​​Firetube Boilers

​In firetube boilers, the name explains the process: the combustion gases run through pipes that are surrounded by the water in a vessel.  The hot water produced will be pumped through the system or the steam produced will be introduced into the steam distribution piping. They have significant benefits, as the capacity range is large, relatively affordable compared to other options, and have inexpensive replacement components. Additionally select firetube boilers that generate hot water can be designed for condensing operation and/or variable water flow operation.  Both of these modes of operation allow for significant energy savings.

​Watertube Boilers

​Watertube options are basically the opposite of firetube boilers. The tubes carry water, and they are surrounded by the hot gases produced by the burners. They can be  more expensive, but can handle much higher pressures and can produce large quantities of steam (steam quantities for process or industrial use). The real question is what is required by the rest of the system.

Condensing Boilers

Although condensing boilers can be configured as either firetubes or watertubes, they distinguish themselves because of a secondary process. Exhaust gases contain water vapor, and when the gases are run over a second heat exchanger, the water vapor in the combustion gas condenses and the energy associated with the phase change is transferred to hot water used in the system. While normal boilers may have efficiency ratings of 80-84 percent, condensing boilers have efficiency ratings well north of 90. 

​Let Us Help You Find the Right Commercial Boiler

Windy City Representatives works with leading manufacturers of commercial boilers and related components, and we understand how important it is to take multiple considerations like budget and existing systems into account when planning and developing hydronic or steam systems commercial or industrial buildings. Call us today at 630-590-6933 to discuss your options.