Information About Boilers
A boiler is a device designed to produce steam or heat water and can be used to provide space and water heating for houses and buildings. Most of the heating systems use natural gas-fired burner as a main heating source. Some of the heating systems use oil fired burners and electric resistance heaters instead. In some particular cases, steam can be favoured over hot water.
Boilers have numerous advantages that have made them a standard component of buildings. Most of them have a long life and efficiencies that can rise to 95% or higher. Boilers are an effective way of heating a building and in case of steam systems, they need minimum or no pumping energy. Steam can hold 5 to 6 times more heat energy than water. Generated at high pressure, it can produce high temperature and energy. Steam is easy to control - it is environmentally friendly and hygienic.
For this reason, a boiler is often considered as a valuable investment when looking for ways to reduce energy use and save money. If you're interested in boilers, we offer you a free, easy to use, without obligations service that, based on your preferences, will give you quotes from different boiler suppliers. You just need to fill in the form on the right.
Major Components of Boilers
The key elements of the boilers involved in this process are the burner, combustion chamber, heat exchanger and controls.
This element of the boiler has a significant role in commencing the combustion process inside the boiler. It receives signals and notification from the temperature sensors when the heat needs to be generated out of the system.
This iron component is where burning process takes place. It is intended to be resistant and experience intense heat energy that can reach very high limits in a short period. Produced heat is afterwards transmitted to the heat exchanger unit.
Several fuel pipes are used to filtrate the liquid inside the combustion chamber. In the next step, water is pumped through pipes to heaters or radiators that emit produced heat energy.
Boiler control helps in the production of hot water or steam in an efficient and safe manner. It controls and monitors boiling water temperature or steam pressure and controls the firing rate.
How Do Boilers Work?
Both oil and gas fired boilers operate by using controlled combustion of the fuel to warm water. Fuel and oxygen are combined in the burner and with the help of ignition devices they create a platform for combustion. The process of combustion is held in the combustion chamber which transfers generated heat to the water through the heat exchanger. Controls are used to adjust the ignition, the burner firing speed, supplies of fuel and air, steam pressure and water temperature.
Hot water is further pumped through the pipes and transferred to equipment throughout the building, which can include hot water coils in air handling units, service hot water heating devices and terminal units. Steam generated by steam boilers circulates through the pipes from areas of high to low pressure, without help from external power sources. In the following paragraphs, different types of boilers are explained and more details on design and particular boiler systems are provided.
Types of Boilers
Boilers can be classified into different categories according to working pressure, temperature, fuel type, draft method, size and capacity. Sometimes this classification can be based on their fundamental components such as heat exchanger materials or tube design. Two primary types of boilers are:
- Firetube Boilers
- Watertube Boilers
The working principle of firetube boiler is based on hot gases of combustion that circulates through a range of pipes surrounded by water. Design of the firetube boiler is ancient, and it was mainly used during the 18th century for steam locomotive engines. The fuel is burnt inside the furnace. Produced hot gases flow through the fire tubes immersed in water inside the main vessel of the boiler. The heat energy generated by gases is transferred to the water. As a result, steam is generated from the water and transferred further for the required purpose.
The watertube boiler uses water flows inside the tubes that are placed in the hot gases from the fire. This system works contrary to the firetube boiler, where gases are passed through tubes surrounded by water. Watertube boilers commonly exist in bigger sizes comparing to firetube boilers. Their size can go up to a few million pounds per hour of steam generated. They are efficient in handling steam pressures and designed to attain intensely high temperatures.
The big difference in types of boilers is the fuel used to heat the water. The frequent practice is to name boilers based on the type of fuel they burn. It can be gas, oil, electricity, renewable energy or solid fuels such as coal and wood.
Natural gas is one of the most popular fuel sources, prepared from methane mixed with a few other gases in smaller proportions. Gas as a fuel contains minimal value of carbon and high value of hydrogen that results in the production of fewer greenhouse gases responsible for global warming. Condensing boilers are the most common type in UK homes and more energy efficient, as compared to other gas boilers.
Oil boilers are mostly condensing boilers fuelled by oil instead of gas. Oil fuels contains lower carbon content that results in reduced emission of carbon dioxide. On the other side, oil produces high amounts of carbon dioxide due to burning. Oil boilers are often more expensive as compared to gas boilers due to their complicated burning mechanism.
Use of electricity in a boiler system (electric boilers) offers various benefits such as compact design, light weight and noise-free working system. In addition, it can be easily employed in diverse kinds of heating and cooling devices such as air conditioning systems.
Renewable energy sources can be used as boiler fuel. Most common ones are biomass, wind and solar power. This way of heating is extremely useful for people living in distant regions where additional fuel sources are high-priced or difficult to achieve.
Solid fuels include coal and wood. Prior to the emergence of fuel oil, they were the only accessible fuels. As compared to other fuel types, the use of coal and wood results in more dust, ashes and emission of polluting ingredients.
Advantages of Home Heating Boilers
There are several advantages of home heating boilers as compared to other home heating systems.
- Cost - Boilers are cost effective. While initial costs of installation are high, operating costs are much lower compared to other heating systems. Year based savings can be as much as £310 on your energy bills.
- Space - Boilers are often smaller than other types of heating systems. Combi boiler can even be installed on the wall instead of taking up floor space. Additionally, newer boilers are smaller in size than older models and will take up much less space in your home.
- Environment - Boilers are considered a top choice when it comes to environmentally friendly heating solutions. Boilers can use renewable sources such as pellets of recycled materials or biodiesel that are carbon-neutral fuels.
- Installation - Boilers are easy to install with the minimum of disruption. Installation should be performed by licensed technicians.
Factors to Be Considered When Investing In a Boiler
- Power Requirement and working pressure
- Steam generation rate
- Availability of fuel and water
- Availability of space
- Portable load factor
- Operating and maintenance costs
- Geographical position of power house
Which Boiler Is Best for Me?
Choosing the right boiler is not an easy task. Whether you are opting for a gas, oil or biomass boiler, the decision will be made based on what is most suitable for your property. The principal issues are: available space, accessibility to the main gas source, size of your property and availability of wood pellets in your area.
Should I Consider Installing a Condensing Boiler?
When possible, it is most effective to install the highest efficiency type of boiler. However, there are some rare situations when installation of Condensing boiler is not recommended. Since March 2008, installation and replacement of oil and gas boilers needs to be condensing according to the Building Regulation in the UK.
What Is a Combi Boiler?
Combi or Combination boilers are capable of providing both hot water and heating within your home. It is a combination of a conventional boiler for radiators and an independent water heater in one unit. Hot water is available instantly but it might require some time to heat.
What Is a Condensing Boiler?
Condensing boilers use less fuel and have low operational costs, as compared to other home heating systems. During the burning process of oil and gas, hydrogen locked within their chemical structure links with oxygen in the air and form water. Generated steam or vapour contains about 8% of the total fuel’s energy which makes modern boilers highly efficient.
Why Should I Replace My Boiler?
Efficiency of a boiler decreases over time. The majority of boilers available nowadays will have efficiencies greater than 90%. Replacement of older type of boilers will result in fuel savings of more than 25%. Moreover, energy bills will be reduced by a quarter.