Vaillant expands its solar thermal range

Press release

  • Technologies

  • Well-designed drainback solar system with a wide range of applications

  • No overheating in the summer months

  • All-in-one solution auroCOMPACT also available as a drainback solar system

The heating and ventilation engineering specialist Vaillant presented its new drainback solar system auroSTEP plus D at the SHK 2016 trade fair in Essen, Germany. The Remscheid-based manufacturer is thus the only company in the market to offer a pressure-free solar technology system that prevents the solar unit from overheating in the summer. Hot water is only produced when it is needed. If there is no heat intake and the hot water cylinder is completely heated up to the desired temperature, the solar pump is switched off. The solar fluid then drains out of the systems’ collectors and pipes, into the tube coil of the cylinder or the solar station’s collecting vessel. This prevents the solar fluid from vaporising and protects the unit as a whole by reducing the thermal load. In pressurised systems on hot days, the solar fluid first has to cool down overnight and recondense so that the system can continue working.

New flat-plate collectors specially designed for drainback solar systems

auroSTEP plus D is available as a 250-litre or 350-litre drainback solar system. It is an independent system with a compact design and is eBUS-enabled, so it can be integrated into the overall system. All the necessary components for solar power generation, such as the solar cylinder, control unit and solar station, are built in. A further new feature is the auroTHERM classic flat-plate collectors, which are specially designed for drainback solar systems.

All-in-one solution auroCOMPACT now also available as a drainback solar system

The only prerequisite for the new solar system is a pipeline gradient between the collectors and the return vessel in the cylinder or the solar station. The system is particularly suitable for places where the capacity utilisation varies considerably, such as hotels, sports centres, commercial properties and public buildings. Drainback solar systems should be used in private households if there is likely to be a noticeable change in hot water requirements, for example, when children leave home.

As a new, particularly compact all-in-one system, the auroCOMPACT solar gas-fired condensing system will also be available as a drainback solar system from 1 April 2016. The product combines a gas-fired condensing boiler, a layered buffer tank and the complete hydraulics all within the same outer casing.

Setting up large systems with auroFLOW plus

For setting up individual drainback solar systems, Vaillant offers the new auroFLOW plus solar station. The basic version can cover a collector surface of up to 15 m². With the extension module, a collector surface of up to 30 m² can be set up. Cascading up to four auroFLOW plus solar stations and extension modules provides large solar surfaces with up to 120 m² of collector surface. In this way, companies with high water requirements, such as breweries or car washes, can now also profit from free solar heat. The heat can be optimally stored in the allSTOR multifunctional hot water cylinder.

About Vaillant

The Vaillant Group is an internationally active company based in Remscheid, Germany, which operates in the fields of heating, ventilation and air-conditioning technology. As one of the global market and technology leaders, the Vaillant Group develops and manufactures customised products, systems and services to provide a comfortable living environment. Its product portfolio ranges from efficient heating devices based on conventional energy sources to system solutions for using renewable energy. In the financial year 2020, the company, which has been family-owned since its foundation in 1874, generated sales of more than €2.7 billion with its workforce of about 15,000.


Jens Wichtermann
Jens Wichtermann

Jens Wichtermann

Group Director Communication, Sustainability & Government Relations

Phone: +49 2191 18 2754

Mobile: +49 175 295 1810

Laden Sie hier das Vaillant Pressekit herunter.

Share press release