Domestic hot water

  • Overview
  • Related products
  • Case studies
  • Learning
  • Articles
  • News

With Danfoss systems you never need to worry about legionella or insufficient or cold water in the bathrooms. Our domestic hot water solutions include water heaters that can be connected to multiple tanks as well as storage and charge systems, hot water valves that prevent legionella and temperature controllers. When used together, these combine the demand for high performance, comfort, hygiene and resource efficient operation – even during peak loads.

Freshwater systems for decentralized DHW heating are either used alone or integrated into a flat station. They only heat the domestic water when needed. If properly planned, the volume of piping between the freshwater system and the taps in an apartment will be below three liters (when legionella testing is not required).

Production of hot water

Production of hot water is done by one of our water heaters. These can be equipped with one or more storage tanks to provide enough hot water at peak loads. They can also be equipped with a storage charging principle. They meet hygienic, safety and temperature requirements and can be connected to different energy sources. Adding hot water valves and temperature controllers help prevent legionella. All together a high performance, comfortable, hygienic and resource efficient production of DHW is achieved.

Distribution of hot water

The hot water is then distributed to the water tap points. In most cases the size of the building requires a series of risers circulating the hot water. Our Thermal balancing valves ensure the proper hydronic balance that avoids long waiting times. As these control the water temperature they also avoid too hot water causing lime, corrosion and energy inefficiency. Normally these valves are set to a temperature that avoids legionella to grow.

Smart and energy efficient legionella risk reduction

The thermal balancing valves can be equipped with thermostatic or electronic disinfection modules, allowing periodic flushing of the system to kill the legionella bacteria. The electronic temperature registration system monitors all the temperatures and initiates the safe and energy efficient disinfection cycle. It also stores the temperature data for logging purposes. The electronic controller can be easy accessed on mobile devices using Wi-Fi or be integrated into Building Management Systems (BMS) for remote control, monitoring and alarm purposes.

Close to the water tap points, there is sometimes a need to lower the hot water temperature. Our hot water mixing valves ensure the outlet water temperature is safe for consumption.

How to balance domestic hot water systems?

What are the issues and challenges in domestic hot water systems in non-residential buildings?See why hydronic balancing is important, what type of balancing is the best and how that can solve the issues.

How we can help you

One partner with high DHW expertise

High performance and energy efficiency

Resource efficient operation

Pass Legionella testing

Lowest possible operating costs

MTCV Thermal balancing valves with CCR2+ electronic controller

Establish safe and energy efficient DHW systems and control them remotely on a mobile device.

Danfoss webinar: Challenges and solutions for effective prevention from Legionella bacteria for hospitals, hotels and residential building

Webinar: Challenges and solutions for effective prevention from Legionella bacteria for hospitals, hotels and residential building

In Europe the number of registered Legionella infections continues to grow every year. Without proper measures the number of infections will continue to grow even more. Due to Covid-19 pandemic, temporary shutdown or reduced operation of a building and reductions in normal water use can create hazards for returning occupants. All in all, the challenges not only relate to achieving a system with reduced risk of legionella contamination. In addition, energy-efficient operation and user comfort are important aspects that require a proper solution.

Join our FREE webinar and learn more about our DHW hydronic balancing and smart disinfection solutions.

For who: Everybody (technical or non-technical) involved in the specification, design, construction, maintenance or service in Domestic Hot Water systems

Topics: During the webinar you will be informed about the typical challenges to maintain both safe and energy efficient operation of DHW systems.

After this introduction we will show you how to overcome these challenges and how to create a safe and energy efficient system.

Language: English
Presenter: Peter Meza, Danfoss product manager

Date: 4th of November 2020
Time: 9:00 – 10:00 AM, CET – Login from 8:50

After your sign up you will receive an e-mail with the confirmation and you can save the webinar in your calendar.

We’re looking forward to your participation!

Related products

  • Self-acting temperature controllers- Danfoss
    Self-acting temperature controllers

    Thermostatic temperature controllers are used to control the flow temperature in instantaneous/storage domestic hot water and heating systems. In multi-family houses and commercial buildings, they are used for hot water systems and for return temperature limitation in district heating applications.

  • Instantaneous water heaters without tank- Danfoss
    Instantaneous water heaters without tank

    The instantaneous water heaters are suitable for smaller households, as they provide hot water when you need it - you get instant hot water. Compared to storage water heaters they do not generate standby energy losses and can therefore save you money.

  • Danfoss Thermal balancing valve MTCV
    MTCV with CCR2+

    MTCV Thermal balancing valves provide a dynamic, temperature based, balancing solution for drinking water applications. Combined with the CCR2+ a smart and energy-efficient electronic control solution for monitoring and disinfecting DHW systems is established.

Case studies

  • Renovation of an apartment building with flat stations, Hamburg, Germany

    Until 2014, the apartments in this multi-family building located in the Hamburg suburb of Bergedorf were heated using electrical water heaters and supplied with domestic hot water using electrical instantaneous water heaters. Now, after the renovation, a block heating station in the basement of the building provides heating distributed via flat stations installed in the stairwell and used for decentralized domestic hot water. Tenants were able to stay in their apartments throughout the renovation process.

  • Domestic hot water for a new apartment building, Weitblick, Germany

    Under the German Drinking Water Ordinance, building owners and managers must ensure lasting prevention of Legionella in the domestic hot water systems used in residential buildings.

  • Flat stations in apartment building in Hamburg, Germany

    Visitors to Hamburg’s Henriette-Herz-Ring who let their gaze drift upward will discover two shipping containers on the roof of the apartment building. They are the visible result of an innovative planning initiative to replace inefficient gas boilers with Danfoss flat stations. The highlight of this renovation: residents did not have to vacate their apartments.

  • Domestic hot water for Selenium twins luxurious residential blocks, Istanbul, Turkey

    The Selenium Twins are two luxurious 34-storey residential blocks located in Fulya, Istanbul. They reside on a 29,000 m2 area of land owned by Besiktas JK football club that includes a 10-storey hospital building, 21-storey office building and 16,000 m2 supermarket.



  • Increased importance for safe Domestic Hot Water systems due to Covid-19

    While the global community is very aware of the Covid-19 virus, another potentially fatal bacteria, Legionella, is causing more and more infections every year. Research even shows a relation between both infections. Read more about the increased risks in DHW systems due to Legionella and Covid-19 in this article.


  • Legionella prevention, the smart way
    Monday, September 24, 2018

    For many years Danfoss has played an important role to establish safe Domestic Hot Water systems in hospitals, hotels, multi-family apartments and other buildings. Now our MTCV thermal balancing valves and new CCR2+ electronic controller for automatic disinfection have been significantly improved to your benefit.