What are the Key Components of a Boiler
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Residential and commercial hydronic heating systems use boilers. This system uses water to heat a home. The boiler heats the water and this system transfers this heat to a radiator or any other distribution source. A hydronic system can use steam or hot water to heat. This depends on the type of your boiler. A boiler uses a tankless coil, boiler nipples and many other parts to work. This article covers the key components of a boiler including: 


A Peerless Boiler or any other boilers need a source of heat that heats the water. A burner provides heat in a boiler. Some boilers use oil and other boilers are gas-fired. 

Heat Exchanger 

The heat produced by the burner needs to be carried to the water without direct contact with the water. This is where a heat exchanger comes into play. 

Supply Lines 

Your hydronic heating system needs supply lines to deliver steam or heated water to the distributor. 

Return Lines 

There is no wastage of water in the system. When the steam in the system changes to the liquid form or water cools, the boiler heats the water again and this cycle repeats continuously. A boiler uses return lines to carry water for re-heating.    


The air and fuel meet in the firebox. This is where a flame is created to produce heat that heats the water in the system.   


This material fills any openings and/or gaps around the firebox. The fire must not escape the firebox.      

Circulator Pump 

A boiler uses a circulator pump to push steam or hot water to the distributors.


Steam boiler systems use deaerator and condenser tanks. Both tanks have almost identical construction but both serve different purposes. Both don’t share pump construction requirements. The tank design uses the following two principles: 

Vacuum Principle 

The pump uses an ejector pump to create a vacuum. As a result, water in the tank starts boiling. This also removes air. Steam turbine applications use this principle. 

Thermo Principle

In this case, the tank is connected to the atmosphere. Smaller plants use this design. The system maintains water temperature around 221°F using steam.    


Usually, large scale power plants have used economizers. However, the industry demands highly efficient boilers. This is the reason why you can find economizers in boilers as well.


It is a device that converts wet steam or saturated steam into dry steam or superheated steam.

A natural gas boiler uses one of the following two types of burners:

  1. Atmospheric burners
  2. Forced draft burners

As there are stringent air quality regulations in place, premix burners are more common now. The combustion process takes place in the combustion chamber made of steel or cast iron. The chamber also contains burners. 

When you are buying a residential or commercial boiler, you must consider the type of fuel you can easily access. Also, make sure that you can easily buy tankless coil and other boiler parts and components for timely repairs or replacements.