Domestic hot water

  • Overview
  • Related products
  • Case studies

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.

Legionella prevention and temperature control

The Thermal balancing valves can be equipped with thermostatic or electronic disinfection modules allowing periodic flushing of the system to kill the legionella bacteria. Our temperature registration system monitors all the temperatures and initiates the electronic disinfection cycle. It also stores the temperature data for logging purposes. The registration system can easy be connected to a PC and sends out an alarm in case too low or high temperatures are registered.

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

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

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.

Related products

  • 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.

  • Thermal balancing valves- Danfoss
    Thermal balancing valves

    Thermal balancing valves provide a dynamic, temperature based, balancing solution for domestic hot water applications. The valves optimize the temperatures in DHW systems having constant hot water circulation. As result heat losses and risk of legionella are significantly reduced.

  • 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.