Residential home in Johannesburg

How one homeowner in Johannesburg navigates the energy maze

Discover the epitome of upmarket living at Waterfall Country Estate, the largest residential enclave in Waterfall City, Johannesburg. Spanning 500 hectares, this secure lifestyle haven offers 934 hilltop and riverside stands ranging from 1,100m2 to 2,000m2. Nestled within this picturesque estate are the Kerbers, led by Hannes, who, along with his delightful family, has chosen to establish their ideal, secure, and cozy home. This residence exemplifies the flawless integration of a Stiebel Eltron heat pump, seamlessly and harmoniously contributing to the realization of the envisioned home, particularly in the realm of energy efficiency. 

The technology used

Our air source heat pump WPL 25 ACS and the combi tank HSBC 300 deliver the domestic hot water and take care of the underfloor heating. 

The WPL 25 ACS Air Source Heat Pump is a top-performing solution for efficient heating, ensuring a warm and cozy interior even in sub-zero temperatures. Its ability to maintain maximum efficiency in freezing conditions makes it ideal for both heating and cooling applications, including traditional radiators and underfloor heating or fan convectors. With inverter technology for high efficiency, low noise emissions, and the option for smartphone control, this outdoor heat pump enhances year-round comfort in new builds or modernization projects.  

The HSBC 300 Integral Cylinder is a space-saving marvel that combines the DHW cylinder and buffer cylinder in a single unit, eliminating the need for two separate cylinders. This innovative design reduces installation space requirements by half, making it ideal for compact spaces. Specifically designed for compatibility with heat pumps, it ensures greater hot water convenience, reliability, and energy savings. The integrated heat pump manager (WPM) simplifies system control, facilitating easy integration into heating or cooling systems. Additionally, it allows the connection of two heating circuits, offering versatility in application. 

The brand choice

The decision to choose STIEBEL ELTRON for your heating system in South Africa is straightforward according to homeowner, Hannes Kerber. This is due to the brand's established presence, known reliability, and the existence of a local company with its own warehouse and personnel. “The familiarity and trust in the brand during our research process played a pivotal role in our selection. Working closely with certified installers recommended by STIEBEL ELTRON, streamlined the installation process. The consultation from inhouse brand experts at the local office ensured a well-planned system that met our specific needs, including hot water, heating, and cooling.” 

From consultation to post-installation service, the experience has been seamless. Regular tweaks and adjustments have been made to optimize energy consumption within the home and this ensures the system's effectiveness, even in the face of potential load shedding or grid outages. The underfloor heating, particularly on vinyl floors, has proven to be a comfortable and enjoyable feature for this family. “The integration of an internet module allows us to monitor and control the system remotely, providing insights into its performance and aiding in ongoing adjustments.” Hannes Kerber expressed. 

Looking ahead, Hannes Kerbers plans involve integrating the system with an inverter and battery backup for enhanced sustainability, especially during periods of extended power outages. Overall, the decision to invest in Stiebel Eltron's technology has resulted in a reliable, efficient, and customizable heating solution, contributing to a content and comfortable living environment. 

More on the WPL and HSBC

Product information


  • Air source heat pump installed outdoors for heating and cooling 
  • Ideal for new build and modernisation 
  • Inverter technology for high efficiency and low energy bills 
  • Low noise emissions due to intelligent appliance design 
  • Operating noise can be further reduced in night mode ("silent mode") 
  • Can be controlled easily via smartphone (additional components required) 
  • Flow temperatures of up to 65 °C for first rate hot water convenience 
  • High energy efficiency class A++/A+++ even when using radiators 

HSBC 300

  • Combi unit comprising a DHW cylinder and a buffer cylinder 
  • For greater hot water convenience 
  • Halves the installation space required for separate cylinders 
  • Compact, reliable and energy saving 
  • Perfect for combination with a heat pump 
  • Can be integrated into a heating or cooling system 
  • Connection of two heating circuits possible 

Increasing self-sufficiency through intelligent energy management

Energy management as a response to rising heating and electricity costs

A well-thought-out energy management system makes sense in the face of high electricity costs. It helps reduce electricity expenses by optimizing self-consumption. Equipped with a corresponding communication interface, you not only can operate your electrical devices with self-generated PV power but also efficiently store excess energy thermally, generated by a heat pump, for example, in a heating buffer or hot water storage. 

Smart software for successful sector coupling

SG ready (SG = Smart Grid) is a simple application to combine a PV system with our universally compatible heat pump: a switching signal, for instance, from your energy management, battery system, or inverter, triggers the thermal storage of surplus PV power by raising the charging temperatures and possibly the room set temperatures. This method is widely used for heat pumps and ventilation integral devices and is supported by numerous commercially available systems, such as energy management systems or inverters. 

This heat pump set includes an advanced air-to-water heat pump for both heating and cooling, along with an integral storage tank. The system features inverter technology, ensuring high efficiency and cost-effectiveness. With a year-round flow temperature of up to 65 °C, it provides excellent hot water comfort and can be used universally, independent of the heating system. 

Take advantage of our all-round support
  • Consultation: We work with you to develop scalable building services concept solutions
  • Design: You benefit from our experience in numerous new build and modernisation projects
  • Installation: We support you with our comprehensive range of services
To your local contact

Data, facts and figures

Waterfall Estate Home


  • Johannesburg, South Africa 


  • Constructed in 2023 
  • Residential home | two story  

Installed technology

  • Heat pump: WPL 25 ACS and the combi tank HSBC300 
  • Operating mode: Heating, Cooling & DHW 
  • DHW Backup: Dual Mode 
  • Heat load: 50W/m² 

Please find more information and details in the following reference brochure: