Loads vary, and a power plant must be capable of handling the minimum load, the maximum load, and any load variations. Boiler selection is often dictated by the variation in load demand, rather than by the total quantity of steam or hot water required. There are three basic types of load variations: seasonal, daily, and instantaneous.
Condensing boilers can achieve up to 98% thermal efficiency, compared to 70%-80% with conventional designs (based on the higher heating value of fuels). Typical models offer efficiencies over 90% when the return water temperature is at 110 ºF or less; the lower the return water temperature, the higher the efficiency gain.
There are so many options to weigh when looking for high efficiency boilers: hot water or steam, wetback or dryback, type of fuel, and more. However, there are a few key considerations to make when evaluating a new boiler for efficiency that will help you no matter what your other considerations may be. Look for a fan that can deliver a stable air supply, a burner and boiler unit that can produce low emissions, a design that maximizes flue gas velocity, smart pressure vessel design, and an efficient heating power to boiler surface ratio are just a few considerations to keep in mind. These simple but powerful design elements are hallmarks of solid construction and will add up to significant performance enhancements. Our team members are always available for consultation and can make specific recommendations when it comes to models once we know more about your needs.
A dryback boiler has a rear wall that is lined with refractory, a wetback boiler has a rear wall that is jacketed by water. Because of this fact, wetback boilers typically boast higher efficiency than dryback boilers as the heat from combustion goes directly into heating water instead of refractory. Wetback boilers are also more forgiving with load changes as the reversal chamber of the boiler is totally submerged in water creating an even heat transfer on the intermediate tube sheet to furnace joint.
One of the most important accessories you can have for your steam boiler is a water softener, which serves several purposes and plays a crucial role in helping your boiler avoid malfunctions and run more efficiently. Let's go back to the basics and walk through how water softeners are used in steam boilers.
Any unusual noises should always be treated seriously.
One of the first things to check if a boiler is unusually noisy is the boiler's thermostat. If the thermostat is malfunctioning, water can become too hot and begin to boil, which could cause loud noises. If the thermostat is broken it may need to be replaced to prevent the water from heating up so much.
Another reason for a noisy boiler could be mineral deposits. As the water heats up inside the boiler, minerals may sink to the bottom of the tank and affect the heat exchange. This may create hot spots within the boiler in which water is overheated, leading to loud noises.
Low water pressure is also a concern that can result in loud noises. If water pressure is low, the boiler is tend to be overheat.
A fire tube steam boiler is a boiler where the combustion gases from the burner are channeled through tubes that are surrounded by the fluid to be heated. The boiler body is the pressure vessel and contains the fluid. In most cases, this fluid is water that will circulate for heating purposes or become steam for use in processing.
Each set of tubes through which the combustion gas passes, before making a turn, is considered a "step". Consequently, a three-step boiler will have three sets of pipes with the outlet located at the rear of the boiler.
In a water tube steam boiler, unlike a fire tube, water circulates inside the tubes. The heat that is generated and the combustion gases that surround the tubes heat the water that circulates inside them. Many water-tube boilers operate according to the principle of natural water circulation.
The capacity of this type of boiler can be enhanced by increasing the number of tubes in the boiler.
