In many homes they are used boilers for heating water, both for showers and kitchens. It is essential to know the most efficient boilers if we want to save on the electricity bill and make the most of the available energy resources. One of the most popular and widespread options are the natural gas boilers.
In this article, you can learn everything about natural gas boilers. From what they are and how they work to which are the best options when choosing, considering the advantages and disadvantages of each type. Are you interested in learning more about this topic? Keep reading!
What are natural gas boilers?
A natural gas boiler This is a device used to heat water or generate heating by burning natural gas. Natural gas is an efficient and clean source of energy compared to other fuels such as diesel or propane. This type of device is found in many homes, taking advantage of the continuous supply of piped gas.
Natural gas is burned inside the boiler to heat the water contained in its tank, which is then distributed through radiators or underfloor heating, providing heating and hot water (ACS). This type of boiler stands out for its energy efficiency, reliability and safety.
How a natural gas boiler works
Natural gas boilers are designed to heat water by burning natural gas. The operation is simple:
- El burner inside the boiler it is activated, starting the combustion of natural gas.
- The heat generated by combustion heats the water that circulates through a closed circuit.
- Hot water is distributed to radiators or underfloor heating systems, providing heating.
- In mixed systems, this water can also be redirected to hot water taps, contributing to the supply of domestic hot water (ACS).
Natural gas is the most common gas in homes with access to piped gas networks. However, there are also boilers that run on propane or butane gas, but these require additional tanks or cylinders, which is often more inconvenient and costly in the long run. Of the available options, natural gas remains the most practical alternative due to its constant availability and low environmental impact.
Main components in a natural gas boiler
- Heat exchanger: This is the part that is responsible for transferring the heat generated by the flame to the water. It can be made of stainless steel or aluminum in the most advanced boilers.
- Three-way valve: A key component in combination boilers, as it allows hot water to be diverted between the heating system or the domestic hot water system.
- Fan: It is responsible for expelling the gases resulting from combustion to the outside, guaranteeing the safety of the system.
- Spark plug: It produces the spark that lights the burner, activating the gas combustion process.
Types of natural gas boilers
There are different types of natural gas boilers, each adapted to different energy needs and budgets.
Watertight gas boilers
Sealed boilers are the most common today. They are characterized by having the fully sealed combustion chamber, which means that they do not use the air inside the home for combustion. This makes them safer, since the gases do not come into contact with the air that is breathed inside the home.
The air needed for combustion is extracted from outside through a system of pipes. In addition, they are more efficient by making better use of the gas combustion process.
Low NOx gas boilers
Low NOx boilers are equipped with advanced technologies that allow reducing emissions of nitrogen oxides (NOx), one of the most polluting by-products of gas combustion. Thanks to an innovative design, these boilers manage to reduce polluting emissions without sacrificing efficiency.
Similar to sealed boilers, these also have a closed chamber, but include a specific system for reducing NOx, making them a more environmentally friendly option for those looking to reduce their environmental impact.
Condensing gas boilers
Condensing boilers are considered the most energy efficient. Unlike other types of boilers, they take advantage of the heat generated by the steam, a product of combustion. In a traditional boiler, this steam is expelled and its energy is lost. However, in condensing boilers, this heat is recovered and reused to heat the water.
This process allows condensing boilers to achieve an efficiency of over 98%, saving up to 30% of fuel compared to conventional boilers. They are also more environmentally friendly boilers, as they generate fewer carbon dioxide (CO2) and NOx emissions.
Atmospheric gas boilers
Although they are becoming less common due to environmental regulations, atmospheric gas boilers are still used in some older homes. These types of boilers have an open combustion chamber and They use the air inside the home to carry out combustion.This poses a potential risk as they can release harmful gases into the indoor environment.
In addition to being less safe, atmospheric boilers are also less efficient than sealed or condensing boilers, which is why their installation is prohibited in most countries of the European Union.
Natural gas boiler prices
The price of natural gas boilers varies considerably depending on the type of boiler chosen, its power and its energy efficiency. Below we show you the approximate prices for the different types:
- Atmospheric boilers: Although their installation is prohibited in many places, the price of these boilers used to be around 300 Euros, being the most economical but also the least recommended.
- Sealed boilers: These boilers have a price range that goes from 400 to 1400 euros depending on their power and efficiency. They are an intermediate option in terms of price and efficiency.
- Condensing boilers: They are the most expensive, with prices ranging between 700 and 2500 eurosThe initial investment is higher, but its high energy efficiency and low consumption more than compensate for the cost in the long term.
Price differences by power
The price of boilers also varies depending on the power we require, measured in kilowatts (kW)The power will depend on both the size of the house and the number of bathrooms:
- For homes up to 80 m² with one bathroom, a boiler of 18 to 24 kW.
- For homes between 80 and 120 m², a boiler of 24 to 30 kW is usually enough.
- In large homes of more than 160 m² and where several bathrooms may be used simultaneously, a boiler of more than 30 kW.
- In exceptional cases, where there are several bathrooms and simultaneous demand for hot water, a boiler with a micro-accumulation tank may be recommended.
Advantages of natural gas boilers
- Energy efficiency: Gas boilers, especially condensing ones, are extremely efficient, which translates into considerable savings on your gas bill.
- Low environmental impact: Natural gas is a fuel that emits fewer pollutants compared to other fossil fuels, such as diesel or coal.
- Relatively low cost: From the 300 Euros, a basic boiler can be purchased.
- Fast heating: Heating and hot water are generated quickly, providing greater comfort in the home.
- Long useful life: Natural gas boilers can last for many years with proper maintenance.
- Low noise level: Modern boilers are very quiet, which contributes to home comfort.
Disadvantages of gas boilers
- regular maintenance: Natural gas boilers require inspection and cleaning at least once a year to ensure proper operation and avoid breakdowns or safety problems.
- Installation cost: Installing a gas boiler can be expensive, especially if there is no natural gas connection and a tank needs to be installed or work done to channel the gas.
In general terms, natural gas boilers represent an excellent option for those seeking efficiency, savings and comfort in their home. Although the initial cost may be higher, especially in the case of condensing boilers, the reduction in energy consumption and lower environmental impact make them a profitable investment in the long term.