Gas boilers are systems that use natural gas or propane as the primary fuel to generate heat. These boilers operate by introducing gas into a combustion chamber, where it is ignited by burners to produce heat. This heat is transferred through a heat exchanger to warm water, which can then be used for heating or to power industrial equipment.

Gas boilers are known for their high efficiency, reaching up to 95% in some models, making them an economical and effective choice in areas where natural gas is readily available. They also produce fewer harmful emissions compared to oil-fired boilers, making them more environmentally friendly. Additionally, gas boilers are easy to operate and require minimal preparation time. However, their usage depends on the availability of a gas network, making them impractical for remote locations lacking proper infrastructure.