How to choose a water heater?

Before choosing a water heater, it is essential to precisely determine their needs because it makes it possible to select the ideal device according to its ability but also its Powerful or its mode of heating. Indeed, a family of six people will not opt ​​for the same water heater as a childless couple, knowing however that if there are only two people at home but very frequently we receive family and friends for a few days, you have to select the right water heater. Natural gas, thermodynamic, electric or solar, indirect or direct heating, are all other criteria to consider before purchasing. Spotlight on the water heater, absolutely essential equipment for the comfort of all.

Choose the power of your water heater wisely

Power is one of first selection criteria since it is very variable from one device to another. In general, the range oscillates between 2 and 30 kW. If you choose too low a power, there is a risk of not being able to benefit from a satisfactory hot water flow. It is considered that to obtain domestic hot water in a small accommodation equipped with a washbasin, a shower and a kitchen sink, it is necessary to have a system of a power included between 17 and 20 kW. For an ultra-equipped dwelling, either we multiply the number of appliances or we install a different water heater.

In order not to make a mistake in your choice in terms of power, you must remember the following.

  • Bath + shower + sink: 25 to 30 kW
  • Bath: 11 kW
  • Shower + sink : 7.5 kW
  • Evier: 5.5 kW
  • Sink alone: ​​4.5 kW
  • Toilet washbasin for example: 3.7 kW.

Difference between cumulus and instantaneous water heater

The cumulus which is also commonly called the ball is a device called accumulation. It stores a certain volume of hot water which it maintains at the right temperature so that the user can enjoy it immediately at any time of the day or night. Depending on the models, it works with different energies (solar, electricity, gas, etc.)

As for the instantaneous water heater, it produces domestic hot water on demand and therefore does not contain any in reserve. It is through an electrical resistance with which the cold water comes into contact that the desired temperature is instantly obtained. There is no risk of “running out of hot water”. It is an appreciable solution in water heatersappoint, to be installed for example in a small summer kitchen which is located far enough from the central heating or in a shower room which is only used occasionally. It is maintenance free, economical and easy to install.

Choosing the right capacity of a water heater

Here are some indications concerning the useful capacity of a water heater according to the uses.

  • 50 litres: small size for reduced water use or for 1 adult,
  • 75 litres: a minimum for a family made up of an adult and a child,
  • 100 litres: suitable for a couple,
  • 200 litres: recommended for a family of four,
  • 300 liters: perfect if you are two adults and three children or for a couple who receive a lot.

It is useful to evaluate your daily water consumption before choosing. For example, washing up by hand requires 25 liters of water, a shower 40 liters and a bath between 120 and 140 liters.

Clearly distinguish the mode of heating

There are two main families of water heaters, namely:

The indirect heating water heater

He is connected to central heating which instantly raises the temperature of the domestic cold water thanks to a diversion system which shortens the heating circuit. In this way, the user hardly waits to obtain very hot water. This process is extremely comfortable, especially in the shower, not to mention that it limits the waste of water since it is not necessary to let the tap run long before it reaches the desired temperature.

The direct heating water heater

It is a device with completely autonomous burner which is therefore not connected to the central heating. As soon as the tap is activated, the water passes through a circuit consisting of a spiral-shaped pipe in contact with the hot gases. Generally, with regard to new generations of direct heating systems, the waiting time for hot water is relatively short compared to older appliances. In addition, the flow is amply sufficient.

The bain-marie system water heater

He represents a compromise between the two previous devices. We appreciate the fact that he generates little limestone because the water is gently heated while being hot immediately. On the other hand, the volume in reserve is quite limited, so that this model is only suitable for a small number of users. Indeed, after two or three successive small showers, you will have to wait to have hot water again since the more you draw, the more the temperature drops.

The different types of water heaters

This device works with different sources of energy. This is a criterion that can weigh in the balance when you are about to select the one that seems to be best suited to your home, the number of people who make up the family, your lifestyle, but also to its budget.

  • The natural gas water heater is connected to the gas boiler. It involves a installation complexe with specific chimney, so that it cannot be placed just anywhere. It is quite economical in a well-insulated home and is low maintenance.
  • The thermodynamic water heater allows divide its energy consumption by 3 compared to an all-electric model. The models offered are adjustable, programmable, but also respectful of the environment, which is why the new thermal regulations recommend it as a device with renewable energy.
  • The electric water heater is the system that can be installed anywhere, whether at home, in an apartment, in annexes such as the garage, workshop, laundry room, bungalow or garden shed, or even in a mobile home (mobile home, motorhome, caravan, etc.) ). For it to work, it only needs a power supply and of course a water supply.
  • The solar water heater is the greenest of all since it uses renewable energy and does not emit any greenhouse gases. Since the energy used is also free, it is economical to use and is eligible for certain bonuses if it is installed by a Recognized Environmental Guarantor professional (RGE). However, it is expensive to buy.

At the slightest hesitation, do not hesitate to inquire with a experienced heating engineer able to help his client make the right choice.

cost of a water heater

The prix of this device varies between 500 and 3800 € on average, of course depending on its power, capacity, brand, mode of operation, etc. If you want to buy an extra water heater, the budget to devote is therefore much smaller than if you plan to install a large state-of-the-art water heater to supply a house with 3 bathrooms, kitchen and sink in the annexes adjoining the building.

Price can be obtained quotation because it is calculated according to many criteria. As an indication, for a standard thermodynamic water heater it is necessary to pay between 2,600 and 2,800 € which includes the installation price by an EGR professional. Note that some financial help are granted under conditions for the purchase of a water heater that meets current standards.

Finally, it is interesting to note that you can save money all year round by opting for a device with a thermal regulation which reduces energy consumption and in addition makes it possible to limit the risk of burns but also of microbes and bacteria which proliferate more readily in water above 55°C.

Leave a Comment