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How to choose your electric water heater

This article provides guidelines for choosing an electric water heater

Buying an electric water heater is not always an easy task simply because technology in this specific area has evolved recently so much, making it difficult, sometimes, to choose the right equipment for your hot water needs.  Water-heaters have a couple of base criteria to factor in as to make the right choice for your household such as the capacity of the tank, durability against hard water, positioning of the tank, and last but not the least, the cost.

As to make it a lot easier for you to navigate through all the necessary specifications and make the right choice, we have rounded up this little article with precise guidelines and great tips on the matter.

Evaluate your household hot water needs

This could be approached fairly easy, as it will suffice to know how many liters of hot water are required by a person daily to assess the right capacity of the water heater. So for example, a water heater with the capacity of 100L would allow for 1 shower, 1 bathroom sink, and 1 kitchen sink, being used at the same time for 1-2 adults. A 150 L water heater would provide enough hot water for 2 adults and a child, servicing a bathtub, a bathroom sink, and a kitchen sink. A water heater with a capacity between 150-200L would offer just enough hot water for 2 adults and 2 children, using a bathtub, 2 bathroom sinks, and a kitchen sink. Finally, a water heater with the capacity between 200-500L can serve a family of 2 adults and 3 children, using at the same time a shower, a bathtub, 2 bathroom sinks, and a kitchen sink.  

Where in my house should I put my water heater?

Placing a water heater in the right space is not an easy task especially if you do not have square meters to spare. Therefore, depending on your house or apartment, you may choose a vertical/horizontal position on the wall or, if living in a house, you may look into buying a water heater that is positioned vertically on the ground. There are a couple of important elements to take into account. First, set up your water heater in the proximity of your bathroom/kitchen, to maximize energy efficiency and make sure the space used is not too cold during winters. Secondly, make sure this space is well ventilated.

Hardness and corrosive aspects of your water

Water heater’s durability is strongly related to the quality of water used and here choosing the right protection is crucial in order to ensure the maximum durability for your equipment. For protection, we have 3 types of technology being used: magnesium anode, steatite, and aci hybride. The magnesium technology is specific to a heating element that is directly immersed in water (feeble protection in highly corrosive water, decent in balanced water).

Steatite technology is in the middle of the pack as the heating element used is isolated from water (not directly plunged), offering to the water heater slightly better protection when used in aggressive water and quite decent resistance in hard water (better than magnesium technology, given the longevity factor in aggressive water).

And for those of you who live in areas with very aggressive water, we present the champion technology which is the ACI Hybride. This technology has been invented and patented by Atlantic, the French leader in water heater production. It has been conceived with only one thing in mind, to provide the best protection against hard and very aggressive water.

Alongside the steatite heating element, they introduced the titanium anode, coated in magnesium, traversed by a flux of electrical current that is projecting magnesium particles onto the walls of the water heater tank, thus creating a protective barrier. This type of water heater will last 2x times as much compared to the rest of the squad. It is a little more expensive than the steatite technology, but absolutely a must for these specific areas in your region. Some of the ACI Hybride water heaters, such as those provided by Thermor, are also equipped with an electronic thermostat that allows up to 8% of energy saving.


The magnesium technology provides the cheapest water heaters on the market, very convenient for low budget (attention, if you know your water to be aggressive, then your electric water heater will require maintenance once a year).  The steatite technology is a viable option for aggressive water and it is worth investing in such a water heater if your water is mildly aggressive even though it is 20% more expensive than the magnesium technology. The ACI hybride is the best by far and the most expensive, but nevertheless, it will pay off long term (does not require regular maintenance).

Finally, if you are not a handyman, then in order for you to be able to enjoy your equipment safely and also to ensure that the installation is up to current standards and quality, we strongly advise resorting to the service of a professional plumber who will give you a warranty for his work and the materials used and access to a reduction on your VAT expenses. Also, a professional plumber will save you a lot of time and hustle when it comes to choosing the best electric water heater for your home.

Author: Stéphane Boldisor (Thermocom.fr)

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