Boiler and Condensing Boiler - Report Example

Boiler and Condensing Boiler Name Tutor Course Date Introduction A boiler is a closed vessel in which water or any other fluid is heated. When using the boiler, the fluid does not necessarily boil but may heat or vaporize before exiting the boiler in order for it to be used for different purposes (Arena, 2010). The condensing boiler has different features which influences its use. Depending on the manufacturer, the specifications have to be followed during the installation as well as the use of the boiler. Factors such as size and energy use greatly influence the selection of the condensing boilers. The condensing boilers have modern features and this has played a vital role in influencing its use (Butcher, 2011). The conventional boilers were not effective as they consumed a high amount of energy. The paper discusses the concepts of boilers and condensing boilers in relation to its use, selection and control. Application of the Equipment The main application of the boiler include heating of water, central heating, power generation, cooking and sanitation purposes (Butcher, 2011).There are different types of boilers depending on tits application. Condensing boiler is one of the boilers that is mainly applied in water heating and is fueled by oil or gas. This type of boiler has gained a lot of popularity in most countries due to its efficiency. In other countries, it is compulsory for this type of boiler to be used for heating water as a means to save energy. The condensing boiler is commonly used for domestic as well as industrial facilities to heat water. Condensing boiler is increasingly replacing the conventional types of boilers. In Europe, it is commonly applied in powering of the domestic central heating systems (Arena, 2010). The concerns by the government as well as lobby groups on the use of energy have played a vital role in increasing its popularity. The condensing boilers are not difficult to install and hence it’s increasing popularity. However, its use is being limited by the high costs involved in its purchase. The application of the equipment in heating water has greatly contributed to lowering the cost as well as the amount of energy consumed. Condensing boiler, Source, Equipment construction The condensing boiler is considered as part of a hydronic heating system. This enables it to heat water through the use of water to transfer the heat to a distribution source. In order for the boiler to carry out its functions, it is equipped with different key components in its construction. Some of the key components include the combustion chamber, burner, heat exchanger, exhaust stack and the controls (Siegenthaler, 2012). The accessories include flue gas economizer which is used to recover heat from the boiler. The burner is used for providing the heat that is used for heating the water in the system. Natural gas or oil can also be used during the heating process by the burner. The heat exchanger allows for the heating process top take place. This is achieved through carrying the heat from the burner to the water without any direct contact with the water. The operation of the heat exchanger can be compared to boiling water in a pot. The supply lines are used for delivering the heated water or steam to the distribution points. The lines are also used for distributing the hot water or steam to the distributor. The return lines are used for bring the water back to the boiler for re-heating when it cools. It also returns the steam that has cooled and changed back to water (Burdick, 2012).The firebox is a key component that enables the fuel of the system to meet the air to create the flame. The refractory is used for filling any gap or opening around the fire box. This ensures that fire is able to stay in the fire box. The condensing boiler is equipped with a circulator pump that is used for pushing the hot water or steam to from the system to the heat distributor of the users. The deaerators and condensers are used in steam boiler systems as the fluid is in liquid form (Burdick, 2012). The pump construction can be carried out through the thermo or vacuum principle. The thermo principle is mainly used in smaller plants for maintaining the water tank temperature at 105 degrees. The vacuum principle has an ejector pump that is used to create the vacuum. It causes the water to start boiling due to low temperature that also removes the air from the water. Specification notes The specifications for the condensing boiler vary depending on the manufacturer (Chen, et al, 2012). The specification notes are provided by the manufacturer in order to ensure proper use of the equipment. The following is specification notes from a manufacturer. Manufacturer’s specifications, Source, HEVAC Ltd The specifications provide detailed information about the condensing boiler including its efficiency and how it can be used or installed. The technical specifications must be followed strictly when using the condensing boiler. Damage to the equipment may occur if the technical specifications are not followed strictly. Selection Procedure and Operation Characteristics The boiler is considered as one of the most important facility in a building. It selection must therefore ensure that it meets the needs of the application. The selection procedure of the condensing boiler must be in accordance with a number of criteria. The boiler industry is one of the most regulated in Europe, USA, Australia and other countries (Chen, et al, 2012). During the selection process, the codes and standards related to the equipment should be considered. The primary use of the boiler must also be considered during the selection process. This is in terms of steam or hot water which influences the operations of the facility. When hot water is being utilized, the temperatures must not be above F. The condensing boiler is mainly applied in heating water and this has to be considered during the selection process. The system load is an important factor that has to be considered during the selection process (Chen, et al, 2012). The system load is usually measured in terms of pounds of steam. The system load is useful in providing more information about the capacity as well as the turndown of the boiler. The system load is comprised of other different types of loads which need to be clearly understood during the selection process. This includes heating load, combination load and process load. The variation in the different types of loads must also be determined selection process. The operations of the burner must be considered when determining the loads during the selection process (Trojanowski, et al, 2016). During the selection process, consideration for emergencies and repairs is important. The number of boilers in the system should therefore be considered during the selection process. This is to ensure continuity of operations in case of failure or maintenance of one of the boilers. Performance consideration is an important factor during the selection procedure. This involves the fuel consumption, emission and efficiency. The performance is the most important factor as it determines the ability to meet the needs of the users. The boiler should not consume more than 10% of the total operating budget of the facility on fuel (Trojanowski, et al, 2016). Natural gas, propane or light oil is the fuel of choice for the condensing boilers (Jones, 2014). The boiler also needs to meet the emission regulation that is in place. This is considering that the environmental issues are increasingly becoming important where the use of fuel and energy is concerned. Efficiency is used as a measure of economic performance for any equipment. In the boiler industry, it is measured in terms of combustion, thermal efficiency, boiler efficiency and fuel to steam efficiency. Combustion efficiency is the ability to completely burn all the fuel. An efficient boiler should operate with 15-20% excess air (Jones, 2014). The effectiveness of the heat transfer in the boiler is the thermal efficiency. The boiler radiation and convention power is however not taken into account in the determination of the thermal efficiency. The boiler efficiency is measured in terms of the fuel to steam efficiency. Two methods are used in the calculation of fuel to steam efficiency. This includes establishing the relationship between the input and output as well as het balance method. The boilers that have higher heating surface per horse power are considered efficient and may end up with less thermal stress. Special consideration is also required during the selection process. In an existing facility, the factors that need to be considered includes total space required, floor space, size and characteristics of the boiler and power source. Thermal efficiency vs return water temperature, Source, Fulton Boiler Company Control Strategies Control of the condensing boiler is vital in ensuring that it operates in the most economic and fuel efficient manner. An embedded system is usually put in place as a strategy to ensure effective control. The use of modulating burners is also an important strategy used for controlling the boilers. The use of the embedded system and modulating burners ensures that the output of the burner is controlled and the best performance is obtained. This is achieved through matching the load with the output. Control valves to regulate and restrict the flow of water are also a control strategy used for the boilers. Pressure independent valves cam control the boilers to a range of below 0.5% of the load (Butcher, 2011). Other valves are capable of accurately controlling less than 1% of the peak flow. The uses of boilers with low burner turn down ratio are also effective in controlling the load and hence contributing to efficiency and effectiveness of the boilers. Heat dumping is a control strategy that is used for boilers to ensure efficiency and economic use of the fuel. This involves diverting the excess boiler heat to the DHW tank when the space heat demand is satisfied (Butcher, 2011). The heat dumping process usually continues until the return temperature to the boiler is lower than the minimum. Heat dumping is a control strategy that has the ability of improving on the overall efficiency of the boiler. Input limits are also being put in place by most of the manufacturers for the purposes of ensuring that the boiler is effectively controlled. The input limits operate by limiting the maximum input of the boiler. The limits usually reduce the cycling where the maximum firing rate is significantly higher. The outdoor resets are also in place for ensuring that the boiler is controlled effectively (Chen, et al, 2012). The outdoor reset allows the designers to match the boiler supply temperature with the load. Some of the boilers have boost controls which are capable of making adjustments to ensure that the temperature is monitored. The outdoor rest controls have other advantages including the ability to improve on comfort as the temperature is matched to the load conditions. Requirements for Energy Efficient Operations The condensing boiler has the ability of achieving 98% thermal efficiency. Heat transfer, boiler size and emitter output are some of the factors that determine the energy efficiency of the equipment. In order for the boiler to be energy efficient, the boiler operating temperature as well as the maximum building water supply temperature has to be 82°C to 93°C (Chen, et al, 2012). A combination burner with the ability to burn two fuels independently can play an important role in ensuring that efficiency is attained. Energy efficiency requires that the fuel should account for only 10% of the operational budget. The boiler should be able to remove as much het as possible from the combustion gases in order to achieve efficiency. Lower stack temperature is therefore required in order for the boiler to be effective in terms of operation and energy consumption. Multiple flue gas passes is an important factor that contributes to the efficiency of the boiler (Burdick, 2012). Multiple passes ensures that the cooling takes place at a fast rate and hence reducing the fuel consumption. The number of controls that have been put in place at the boilers influences the energy consumption and efficiency. Condensing boiler efficiency curve, Source, ASHRAE A single variable speed pump can be useful in improving on the efficiency of the boiler. The pump has the ability of sending the return water to the boiler and heating coil. The presence of bypass systems as well as valves controlling the flow can be influential in reducing the energy consumption. The boilers with low minimum water flow requirement are an important aspect that determines the efficiency and energy consumption (Burdick, 2012). An automatic mechanism for shutting off the boiler is currently being utilized in order to ensure that it is energy efficient. In most cases this is dependent on the weather as well as the ability to meet the needs of the users. The rest controls plays an essential role in enhancing on the efficiency. It is important for the boilers to be equipped with the rest controls. The rest controls is based on the decrease in loads depending on the temperature. Spatial requirement considerations with maintenance clearance The condensing boiler requires higher maintenance due to condensate production. The maintenance information is usually provided by the manufacturers in the boiler manual (Siegenthaler, 2012). This may include the daily, weekly, monthly or annual maintenance activities. The site conditions may influence the maintenance process of the boilers. In case of a new boiler, installation inspections have to be made after three months of operation. This is for ensuring that the boiler is working in according to the specification and as required. Improper maintenance of the boiler may lead the warranty being denied. The heat exchanger is one of the areas of special concern in the condensing boiler. Black liquid may be experienced as a result of the operations of the boiler (Siegenthaler, 2012). This therefore requires the condensate trap to be checked and cleaned in order to rain the system. The combustion chambers needs to be checked at least 3 to four months of operations. The condition of the combustion chamber is an important factor that governs the maintenance activities. Cleaning and removal of the residues is an important operation that has to be carried out at least after every three months. This is due to the residues that are deposited on a regular basis. Other Considerations The installation of the boiler is an important aspect that has to be carried out carefully and in accordance with the specification. Special provisions in the building may be required in order to ensure that the boiler is properly installed. The site of the installation should be firm and leveled so as to avoid operational challenges. Excessive vibrations may be generate during the operation of the boiler if it is not installed correctly or on a well leveled surface (Siegenthaler, 2012). Excessive vibrations have the potential of contributing to an increase in energy consumption due to heating and high temperatures. The size and characteristics of the boiler are therefore important and should be considered during the design process. The size of the boiler influences various factors including the performance, energy consumption as well as the flows size. The boiler must be installed in a spacious place so as to allow for easy access and maintenance (Butcher, 2011). A part from the efficiency of the boiler, its cost is an important factor that should be considered before a purchase decision is made. All the technical specifications must be considered during the installation as well as the maintenance of the boiler. Conclusion In conclusion, it is evident that the main application of the condensing boiler is heating water. The boiler has several key components which include combustion chamber, burner, heat exchanger, exhaust stack and the controls. Each of the key components has a unique function that enables the boiler to function effectively. The boilers usually have specifications from the manufacturers and should be considered during the selection process. The specifications mainly comprise of the engineering and design characteristics of the condensing boiler. The selection process requires various criteria to be considered. It is evident that the boiler has the ability to achieve 98% thermal efficiency. The control strategies are useful for ensuring that the boiler is able to operate in a fuel an economical and fuel efficient manner. It is evident that the condensing boiler requires high maintenance practices to ensure efficiency. The installation of the boiler has to be effective to avoid excessive vibrations that impacts negatively on its performance. Bibliography Butcher, T., 2011. “Performance of Combination Hydronic Systems.” ASHRAE Journal, pp.36–41. Arena, L., 2010. “In-Field Performance of Condensing Boilers in Cold Climate Region.” National Energy Technology Laboratory, Morgantown, WV; U.S. Department of Energy, Building Technologies Program. Siegenthaler, J., 2012. “Modern Hydronic Heating for Residential and Light Commercial Buildings, 3rd Edition.” Mohawk Valley Community College, Utica, NY. Burdick, A., 2012. “Strategy Guideline: HVAC Equipment Sizing.” National Energy Technology Laboratory, Morgantown, WV; U.S. Department of Energy, Building Technologies Program. Chen, Q., et al., 2012. Condensing boiler applications in the process industry. Applied Energy, 89(1), pp.30-36. Trojanowski, R., et al., 2016. Polymer heat exchanger design for condensing boiler applications. Applied Thermal Engineering, 103, pp.150-58. Jones, D., 2014. Principals of condensing boiler system design. ASHRAE Transactions, 120(1). Read More

The supply lines are used for delivering the heated water or steam to the distribution points. The lines are also used for distributing the hot water or steam to the distributor. The return lines are used for bring the water back to the boiler for re-heating when it cools. It also returns the steam that has cooled and changed back to water (Burdick, 2012).The firebox is a key component that enables the fuel of the system to meet the air to create the flame. The refractory is used for filling any gap or opening around the fire box.

This ensures that fire is able to stay in the fire box. The condensing boiler is equipped with a circulator pump that is used for pushing the hot water or steam to from the system to the heat distributor of the users. The deaerators and condensers are used in steam boiler systems as the fluid is in liquid form (Burdick, 2012). The pump construction can be carried out through the thermo or vacuum principle. The thermo principle is mainly used in smaller plants for maintaining the water tank temperature at 105 degrees.

The vacuum principle has an ejector pump that is used to create the vacuum. It causes the water to start boiling due to low temperature that also removes the air from the water. Specification notes The specifications for the condensing boiler vary depending on the manufacturer (Chen, et al, 2012). The specification notes are provided by the manufacturer in order to ensure proper use of the equipment. The following is specification notes from a manufacturer. Manufacturer’s specifications, Source, HEVAC Ltd The specifications provide detailed information about the condensing boiler including its efficiency and how it can be used or installed.

The technical specifications must be followed strictly when using the condensing boiler. Damage to the equipment may occur if the technical specifications are not followed strictly. Selection Procedure and Operation Characteristics The boiler is considered as one of the most important facility in a building. It selection must therefore ensure that it meets the needs of the application. The selection procedure of the condensing boiler must be in accordance with a number of criteria. The boiler industry is one of the most regulated in Europe, USA, Australia and other countries (Chen, et al, 2012).

During the selection process, the codes and standards related to the equipment should be considered. The primary use of the boiler must also be considered during the selection process. This is in terms of steam or hot water which influences the operations of the facility. When hot water is being utilized, the temperatures must not be above F. The condensing boiler is mainly applied in heating water and this has to be considered during the selection process. The system load is an important factor that has to be considered during the selection process (Chen, et al, 2012).

The system load is usually measured in terms of pounds of steam. The system load is useful in providing more information about the capacity as well as the turndown of the boiler. The system load is comprised of other different types of loads which need to be clearly understood during the selection process. This includes heating load, combination load and process load. The variation in the different types of loads must also be determined selection process. The operations of the burner must be considered when determining the loads during the selection process (Trojanowski, et al, 2016).

During the selection process, consideration for emergencies and repairs is important. The number of boilers in the system should therefore be considered during the selection process. This is to ensure continuity of operations in case of failure or maintenance of one of the boilers. Performance consideration is an important factor during the selection procedure. This involves the fuel consumption, emission and efficiency. The performance is the most important factor as it determines the ability to meet the needs of the users.

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