Before investing into any boiler unit of any brand, we believe, an individual must have an idea about what is the unit; he/she is going to buy, composed of in order to gain the maximum access over the system and for not getting fooled by the sellers during the purchase.

This article is especially composed to serve the readers with all the facts and figures they must know about their systems, being a buyer.

A boiler is an independent combustion system that sustains in the form of a closed vessel that is used to heat water or other liquids or generate steam by direct application of the energy from the combustion of fuels using electricity or nuclear energy.

Hydronic heating system

For the sake of intense understanding of the unit, the boilers are a part of the hydronic heating system that operates to heat the house by using water to transfer heat to a distribution source, like a radiator. These boilers are a part of the heating system that heats the water to be distributed.

Common Boiler Outlets

The Hydronic heating system comes with 3 main outlets-

  • Radiators- The water, after being boiled is pumped into the radiators or the baseboard heaters, to give off the heat energy produced.
  • Baseboard heating- Baseboard heaters, works similar to the radiators and are installed to help the boiler heat water and send it to the distribution channels through pipes that form the supply lines.
  • Hydronic radiant floor heating- The Hydronic radiant floor system pump the heated water from a boiler through a tubing laid in a pattern under the floor.


All the boilers with different designs come with one thing in common, ‘its basic parts’ that includes a burner, a combustion chamber, heat exchanger and the pluming apparatus. Besides the basic elements, a boiler system accommodates a bunch of other key constituents that perform individual roles in its functioning that are worth considering.

  • Burner- the burner plays the heart of the boiler as it is meant to initiate the combustion reaction within the unit. To be demonstrated technically, the thermostat sends an electric message to the burner, according to the system requirements for the production of heat, which then pumps the fuel in, from an outside source, to get ignited by the burner.
  • Combustion chamber- whole of this reaction takes place in the combustion chamber that is willingly and carefully constructed with cast iron to make it strong enough to endure the temperature that can rise to several hundred degrees, usually in a very short time. The heat generated in the process by now is transferred to the system’s heat exchanger.
  • Heat exchanger- the heat exchanger allows the heat from the combustion chamber to heat the water in the boiler’s tank. It works to transfer the heat from the burner to the water without getting into any direct contact with the fluid. The heat exchanger is made of cast iron or steel to house the burner and the process of combustion. In case of the hydronic heating system, this boiling water is then pumped into the baseboard heaters or radiators through pipes to give off the heat energy produced.
  • Supply lines- the heated water or steam is pumped to the distribution sources through the pipes that are marked as the supply lines.
  • Return lines- the cooled water or steam that cools down into the state of water, is then send back to the system through a piping (or return lines), for the purpose of re-heating.
  • Firebox- validating its resemblance to the name, the firebox is the area where the fuel comes in contact with the flame, producing heat to boil the water in the boiler. Most of them are designed to be in the shape of the box, thus defining its name.
  • Refractory- These are actually the refractory materials that are used to fill up any gap or openings that might occur in the firebox in order to ensure that the fire stays in the box.
  • Circulator pumps- these pumps are used to inject the hot water or steam to the distribution points in the house, via the supply lines to ensure proper circulation in the process.
  • Fuel sources- In order for a boiler to heat the water or convert it into steam, a fuel source is required to release its energy in the form of combustion. Though boilers can run on a number of fuel sources including coal and wood, heating oil, kerosene and liquid propane are still in common.
  • Expansion tank- A small tank that is placed off the main boiler, is used to protect the system from excessive pressures.
  • Backflow valve- The Backflow valve is a safety device that is installed in order to ensure the flow of water in a single direction.
  • DE aerators/Condenser- the deaerators and the condenser tanks, are used to preheat a boilers feed water system n order to remove the oxygen from the water. To be noted, each of the two can only be used in the steam boilers, with an eliminated use in the hot water or oil systems. With an identical construction, each of the two is diverged on the roads of objective. However, the principals of thermo and vacuum are taken much into consideration while designing either of the tanks.

For a detailed study

  • Thermo principle- A tank running on the thermo principle is connected to the atmosphere and happens to be found mostly in smaller tanks where the steam is used to maintain a temperature of around 105°C, to remove oxygen from water.
  • Vacuum principle- A vacuum is created in the tanks by the use of an ejector pump which causes the tank water to start boiling as a result of low temperature, which in return, removes the air from the water. This principle is preferably used for the steam turbine applications. 
  • Other than this, there are 3 backbone components of any boiler system-
  • Boiler Feed Water System- It works on the regulation of the feed water to convert the fluid into steam. There are 2 types of feed water system- in a boiler-
  • Open feed system
  • Close feed system

                   Additionally, there are two main sources of feed water-

  • Condensed steam returned from the processes
  • Raw water arranged from outside the boilers plant processes
  • Boiler Steam System- the steam systems are meant to be responsible for the collection and control of all the generated steam, via pipes, throughout the process, using parts such as valves, steam pressure gauges etc.
  • Boiler Fuel systems- Fueling, being the heart of the process, consist of all the necessary components to feed fuel to generate the required heat.

Each of these facts, as recommended, should be considered by the customers, at least once before going to make a purchase.

Add a Comment

Your email address will not be published. Required fields are marked *