Gas is an interesting energy, especially when you are connected to town gas, or natural gas. Less polluting than fuel oil and less expensive than electricity, it combines performance and energy savings.
However, if this type of device has many advantages, there are so many models that finding your way around and making the right choice is not always easy. Our experts will guide you in your purchase, provide you with their advice and inform you about prices for your comfort!
What are the characteristics of a gas boiler?
The main characteristic of the gas boiler is that it is an economical heating system. To suit all needs, it comes in several types, hanging systems and sizes. It is sized in particular according to the surface to be heated within the dwelling and the condensing models are the most interesting in economic and ecological terms when it comes to heating large dwellings.
The gas boiler can be only intended for heating the house, or it can also produce domestic hot water, or DHW. In this case, it is called mixed or double service. The evacuation of smoke is possible thanks to three means: the suction cup system, the so-called natural draft and the VMC.
It is also necessary to choose the fuel, since a gas boiler can use both town or natural gas and propane gas. However, the options differ between the two modes. In addition, to benefit from a good level of heating, the useful power must be 20% higher than the heat loss from your home.
When and why to change your boiler to gas?
Even if its lifespan is longer, a boiler that is more than 15 years old can be replaced by a more efficient model to save energy – and therefore money – and to improve safety and comfort.
In addition, state aid can make this type of purchase particularly attractive in financial terms, since energy renovation is one of the government’s priorities.
How does a gas boiler work?
The gas boiler is equipped with a burner which heats the water it contains to 40° or 90° depending on the model. This is then distributed within the home, through a heating network divided into supply pipes, to hot water radiators or underfloor heating. There are two types of gas boilers: the low temperature system and the condensing model, which is more efficient.
Choosing the right gas boiler: which model to choose?
There are three types of gas boilers: low temperature models, condensing models and mixed models.
The low temperature gas boiler
This model heats the water up to 40°. It is more economical to purchase and allows savings of nearly 20% compared to a conventional boiler model. However, its efficiency remains lower than the condensing boiler.
The low temperature gas boiler can be with flue or chimney for evacuation.
- The suction cup system has the advantage of avoiding the installation of a chimney flue and therefore sometimes major work. It has two circuits, one for the arrival of air from outside and the other to evacuate the fumes. Its tightness allows it to be installed in a closed room without danger.
- The chimney system, on the other hand, draws the air it needs from the room where the boiler is located, which does not make it airtight and limits, or even prohibits, its use in closed rooms. The evacuation of smoke is possible thanks to a pipe tube of chimney.
The low-temperature boiler is suitable for: housing that is not very spacious, well insulated, and for those who do not want to invest in an expensive boiler model.
The gas condensing boiler
This model works by heating the water to a temperature of around 90°, for an interesting yield of over 105%. This system works on latent energy, in other words the energy produced by the condensation of the fumes emitted and containing water vapour.
This device is more expensive to buy, but it is more economical to use since, by consuming less gas, it saves up to 30% compared to a conventional model, and up to 10% against a low temperature device.
It does not require a conduit and works by means of two suction cup circuits. It draws the necessary air from outside and evacuates the fumes via another circuit.
The condensing boiler is suitable for: those who have high heating and domestic hot water needs, those who are ready to spend more on purchase to save more later, those who wish to benefit from the tax credit and those who can connect the boiler to sewage.
The mixed or dual service boiler
This device produces domestic hot water, or DHW, in addition to producing heat for heating the house.
There are three types of hot water production: the storage system, the micro-storage system and the instantaneous system.
- The storage boiler : the hot water produced is stored in a tank, the dimensions of which can be chosen according to need. Bulky, it is also more comfortable.
- The micro-accumulation boiler : only 3 to 5 liters of hot water are stored in the tank. This reserve makes it possible to quickly have hot water available until a larger volume is heating.
- The instantaneous boiler : this compact model is ideal for small hot water needs, but it is not recommended for houses with several bathrooms and large families.
Choosing the right gas boiler: a wall-mounted or floor-standing model?
The wall-mounted gas boiler
This is fixed to one of the walls of the house. Thanks to its reduced size, it is ideal for small homes. However, it is not enough to cover the heating and hot water needs of a large family and its lifespan is shorter than a floor model.
The wall-mounted boiler suitable for those with a reduced budget and small accommodation.
Floor standing gas boiler
This larger model needs space and is therefore rather recommended in large homes that have a dedicated space. In addition, its large hot water tank can quickly meet the needs of a large family. On the other hand, it is more expensive to install than its wall-mounted cousin.
The floor boiler suitable for those who have the possibility of spending more, those who have a large dwelling and those who have significant heating and hot water needs.
How much does a gas boiler cost?
A gas boiler can be more economical and advantageous to purchase than its electric, oil, hybrid and wood equivalents. Count an average of 500 euros to 8,000 euros for a gas model, against 1,000 euros to 4,000 euros for an electric boiler, 1,700 euros to 10,000 euros for an oil-fired appliance and 5,000 euros to 20,000 euros. euros for a wood boiler.
For the installation of a gas boiler by a professional service provider, count between 500 euros and 1,500 euros. The price is likely to vary according to the model chosen, the context and the ease of installation, the prices charged by the service provider and the geographical area.
How to benefit from state aid to equip yourself with a gas boiler?
Only efficient and quality boilers can allow you to benefit from financial aid from the State. A low-cost model will not allow you to do this. In addition, the device must be installed by a qualified craftsman RGE (Recognized guarantors of the environment) and a certificate must be issued to you.