Heat recovery from shower water

With our innovative, double wall safety tubes, the previously unknown potential of heat recovery from grey water can be utilized.


Did you know that in Central Europe around 65% of domestic hot water is used for showering? Around 10 kWh is needed to heat 200 liters of water from 10 to 55 degrees Celsius. The thermal energy of the water is only used for a very short time and then disappears mostly down the shower drain.


With shower water heat recovery, a large part of the energy amount can be extracted from the draining hot shower water to preheat the incoming cold water. With this technology, the simultaneous occurrence of hot waste water and cold fresh water is used to efficiently reduce the energy requirement without the need for auxiliary energy or storage.

The double-walled design of our innovative safety tubes ensures that domestic hot water and drain water are separated reliably and in accordance with standards. In addition, leaks can be detected through leakage channels.

Made of copper and featuring an optimized design, Wieland safety tubes offer highest heat transfer performance even in bent condition. We can offer a portfolio for your system design or adapt to your individual concept requirements.


Horizontal heat recovery systems: To integrate the heat transfer unit into the shower drain or below the shower surface, Wieland safety tubes are carrying cold tap water on the inside and surrounded by hot shower drain water on the outside.

Vertical heat recovery systems: Safety tubes for shower pipe heat exchangers have a larger cross-section with falling drain water on the inside and cold tap water to be preheated in counterflow on the outside. These systems are used instead of a classic downpipe in the basement or one floor below the shower.

Your benefits at a glance

  • Best heat transfer: Our innovative double wall safety tubes made of copper offer highest heat transfer performance to enable highest requirements of energy efficiency for your system.
  • Safe: Trust in reliable separation of fluids using Wieland safety tubes according to DIN EN 1717.
  • Compatibility: Can be used in DWHRD (Drain Water Heat Recovery Devices) in accordance with DIN 94678
  • Certification: With Wieland safety tubes, tap water certification by DVGW and KIWA product certification (BRL K656) is possible for your system.
  • Flexible: We offer various tube dimensions and designs that are perfectly matched for integration into your WWHR (Waste Water Heat Recovery) system.


You can find further information on Wieland safety tubes here
GEWA-safe double-wall tubes

Frank Dollinger
Product Management Heat Exchangers