Choosing between an instantaneous water heater and a cumulus can be difficult, as each type has advantages and disadvantages depending on your needs and installation. Understanding the differences between these two systems will help you make the right choice for your home. In this article, we explain the particularities of each appliance to guide you in your decision.
Instantaneous water heaters: operation and advantages
How does an instantaneous water heater work?
An instantaneous water heater, also known as an instantaneous flow heater, heats water on demand, i.e. the water is heated only as it passes through the appliance. Unlike a cumulus, there is no storage tank. When you open the hot water tap, cold water enters the appliance, where it is heated instantly by a heating element or heat exchanger.
Advantages of instantaneous water heaters
- Space-saving: Instantaneous water heaters do not require a storage tank, which saves a considerable amount of space, making them ideal for small spaces.
- Hot water on demand: You have an unlimited source of instant hot water as long as your appliance is in operation. So there’s no risk of running out of hot water.
- Energy efficiency: Instantaneous water heaters only heat the water that’s actually being used, so there’s no need to use energy to keep water at temperature in a tank. It is therefore more energy-efficient in the long term.
- Fast installation: The installation of an instantaneous water heater is generally faster and less costly than that of a cumulus, as there is no tank to install.
Disadvantages of instantaneous water heaters
- Limited flow: The instantaneous water heater may have a limited flow rate, which means you may have difficulty supplying hot water to several consumption points (taps, shower, etc.) at the same time.
- Dependence on incoming water temperature: In winter, if the cold water is too cold, the instant water heater may have difficulty maintaining a constant hot water temperature, especially if the flow rate is high.
- Electrical or gas installation: Depending on the model, an instantaneous water heater may require a powerful electrical or gas connection to operate correctly.
Cumulus: operation and benefits
How does a cumulus heater work?
The cumulus, or storage water heater, operates differently from the instantaneous water heater. It has a tank in which water is heated and stored at a constant temperature, generally between 55 and 60°C. When you turn on a hot water tap, hot water is drawn directly from the tank, and cold water is introduced to be heated in turn.
Cumulus advantages
- Storage capacity: The main advantage of the cumulus is its ability to store large quantities of hot water. This makes it ideal for households with a high demand for hot water (several users at the same time, bathtub, etc.).
- Constant temperature: Water remains at a constant temperature in the tank, so you don’t have to worry about the water temperature every time you use it.
- Larger tank: Cumulus heaters are available in a wide range of sizes, from small-capacity models for apartments to larger models for houses.
Disadvantages of the cumulus
- Energy consumption: As the water is constantly heated and stored in the tank, energy is lost in maintaining the temperature. Even if you don’t use the hot water, the cumulus continues to consume electricity or gas to maintain the temperature.
- Space : The cumulus takes up more space than an instantaneous water heater, which can be a problem in confined spaces.
- Risk of hot water shortage: If you use up all the hot water stored in the tank, you risk running out of hot water before the tank heats up again.
Which water heater to choose?
The choice between an instantaneous water heater and a cumulus depends on several criteria:
- Available surface area: If you’re short of space, an instantaneous water heater is more suitable because of its compactness.
- Hot water demand: If your household uses a lot of hot water simultaneously, the cumulus is probably the best option, thanks to its storage tank.
- Energy efficiency: If you’re looking to optimize your energy consumption, an instantaneous water heater will be more advantageous, as it heats only the water you need, with no additional consumption to maintain a constant temperature.
- Budget: Instantaneous water heaters are often cheaper to buy and install than cumulus heaters, although this depends on the specifications and capacity chosen.
Discover our services
At Leader Services, we help you choose the water heater that best suits your needs and your home. Our experts will advise you on the advantages of each system, whether instantaneous or cumulus, and ensure professional installation.
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If you have any questions or would like a quote for the installation of your water heater, please contact us via our contact form. Our professionals are here to help you choose the solution best suited to your needs.
