A dirty boiler tube is an inefficient boiler tube. While some degree of soot build-up is inevitable in any boiler system, excessive soot may indicate serious furnace or fuel issues that result in dramatic decreases in efficiency.
In firetube boilers, hot gases flow through tubes carrying the byproducts of combustion. Over time, these accumulate to form deposits on the inside of the tube surface. The heated water that surrounds firetubes then has greater difficulty transferring heat to the tube, forcing the boiler to work harder.
The inefficiencies caused by this problem can escalate quickly. In fact, soot is five times more effective at insulating than asbestos, which means that a layer of soot just a few millimeters thick can result in significant heat loss and higher fuel consumption.
In watertube boilers, water flows through the tubes that are encircled by the heat source. The high temperature leads to the deposition of dissolved solids, which are naturally present in the water. Similar to firetube boilers, these deposits build-up over time and create heat transfer issues that reduce overall efficiency.
While some build-up is normal in boilers, large deposits can indicate a problem with your furnace or fuel. Excessive soot build-up can occur if the furnace is dirty or clogged or if there is insufficient draft. A low air-to-fuel ratio can also facilitate build-up. As a general rule, lower-grade fuel generates more soot and scale than higher-grade.
Cleaning tubes is essential to preventing soot build-up and maximizing boiler efficiency. Manual brushing and vacuuming of firetubes, as well as pumping chemical solutions through water tubes are common cleaning methods that should be performed a minimum of once per year. Doing so will help to reduce fuel consumption, reduce maintenance costs, and extend the overall life of your boiler.
Honiron is an industry-leading designer and manufacturer of processing equipment, including heat exchangers, condensers, strippers, evaporators, and extractors. For more information or to speak with one of our qualified experts, contact us today.