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Replacing gas boilers

Prices, options, information

Outdated gas boilers are not only a drain on your funds, they also pollute the environment. It is worth replacing a gas boiler to heat your home more efficiently, protect the environment and save money in the long term.

What are the benefits of a new gas boiler?

Investing in a new gas heating system has the great advantage that both domestic water and your living space will warm up more quickly. Modern gas boilers provide hot water in a flash. Furthermore, annual maintenance is fairly simple, which keeps servicing costs correspondingly low.


New gas boilers are also much cheaper than new oil or pellet heating systems. The cost of a new gas heating system will be quickly recouped thanks to modern control and condensing technology and the many funding opportunities currently available.

How does a gas boiler work?

Gas combi boilers are equipped with a burner that burns gas to generate thermal energy. This is used to heat the home and for domestic hot water. Compared to old appliances, modern gas boilers, also referred to as gas condensing heating systems or gas condensing boilers, use control technology that is much more efficient.

As soon as you need hot water or heating in your house, they open the gas line and trigger the ignition. The heated water is pumped around the heating circuit by a circulation pump until the room in question has reached the desired room temperature.

As modern gas boilers make use of thermal energy from the combustion process, this can raise their efficiency by around 30%. So, in the long term, you not only save money, you also reduce emissions.

The graphics show the difference between non-condensing and condensing boilers.

When should I replace my gas boiler?

Unfortunately, there is no general rule that defines when the time has come to buy a new gas boiler. The normal service life of a gas heating system is around 15 to 20 years, but you should not stretch this life span too far as the efficiency of heating systems drops as they age. This can have a further negative impact on emission levels and annual operating costs.

What kinds of gas combi are available?

Consumers can choose between

  • compact boilers or
  • combi boilers


Compact boilers have a very high heating output and are even suitable for use in detached houses thanks to the integrated hot water cylinder.

In contrast, combi boilers heat the hot water using an instantaneous water heater and take up very little room as a result. Furthermore, the price of replacing a gas combi boiler is low.


It can often be worth combining a gas heating system with a heat pump. This type of hybrid heating system is not only particularly environmentally friendly, it also helps to save you money due to its high efficiency.


Combining a gas boiler with solar thermal technology is also effective. WOLF solar heating systems use solar collectors to absorb sunlight and heat DHW and/or back up central heating systems with the captured energy.

What to consider when replacing a gas boiler?

There are several points to consider when purchasing a new gas heating system. Therefore, it would be wise to contact an expert beforehand.


Heating experts not only can check your annual heating requirements and existing exhaust system, they can also align the heating output of the gas boiler with your personal needs. Space requirements are also a very important consideration when buying a system.


When installing a new gas boiler, many consumers also consider adding thermal insulation to their detached houses to lower the annual operating costs still further. If you are switching from a non-condensing to a condensing boiler, it may be necessary to convert your chimney or have it fitted with a plastic or stainless steel pipe.


Conclusion: yes, purchasing a new gas boiler makes sense

Purchasing a new gas boiler has many advantages. The new heating system will pay for itself after only a few years due to its high efficiency and low consumption levels.


If you are eligible for subsidies, for example if you incorporate renewable energies into the system, the price of replacing the gas boiler can fall even further.

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