Air/water heat pumps with new output sizes for new builds and existing buildings alike

Allendorf (Eder),  Apr 6, 2023 – In order to limit climate change and break Europe’s reliance on fossil fuels to the greatest extent possible, an accelerated shift towards renewable energies is an absolute must. As far as the heating sector is concerned, this means, first and foremost, that there is no alternative to the extensive use of heat pumps for home heating and DHW generation, both in new and existing buildings. This is why Viessmann is expanding the output range of its Vitocal 250 series monobloc heat pumps to include five new output sizes. The company is also introducing the Vitoset climate-control ceiling, an innovative panel heating and cooling system that also expands the application area of heat pump technology.

Vitocal 250-A and 252-A: expansion of output range opens up potential for new applications

With the  Vitocal 250-A  and Vitocal 252-A monobloc systems (2.6 to 13.4 kW) launched two years ago, Viessmann introduced a new generation of air/water heat pumps which, using the natural R290 refrigerant, easily achieve flow temperatures of 70°C, even when outside temperatures are very low. This means that customers are no longer forced to install floor heating and, in existing buildings, can simply continue to use their existing radiators.

Designed for new builds with heat output of up to 8.0 kW

Even in new builds with good thermal insulation, requirements sometimes call for higher system temperatures, for example, for DHW generation. The new output sizes ranging from 2.1 to 8.0 kW (at A7/W35) are now available for cases like these. Either the wall-mounted Vitocal 250-A boiler or the floorstanding compact Vitocal 252-A device, with an integrated 190-liter DHW cylinder, is combined with one of the new A4, A6 or A8 external units.

Greater output for bigger existing buildings

The new, more powerful versions with heat output of up to 18.5 kW are ideal when it comes to modernizing heating systems in larger existing buildings with high heating loads. The existing internal units of the wall-mounted Vitocal 250-A or the compact Vitocal 252-A device are once again combined with the A16 or A19 external units. For heating loads in excess of 20 kW, two devices can be cascaded using new control functions.

Vitocal 250-A series offers outstanding features: highly efficient, particularly quiet and quick to install

One thing all of the systems in the Vitocal 250-A series have in common is the highly efficient use of the utilized energy. A COP (coefficient of performance) of up to 5.4 (at A7/W35 under EN 14511) ensures low operating costs: the heat pumps can use one kWh of electricity and free heat from the outside air to generate more than five times the usable heat for heating and DHW generation. Vitocal 250-A and Vitocal 252-A can also be used to cool the building on warm summer days if the customer so wishes. Thanks to this additional advantage, the systems enable a high degree of climate comfort at home all year round.

The Vitocal 250-A series heat pumps also stand out thanks to their very quiet operation. Advanced acoustic design makes the pumps among the quietest of their kind. Low-noise fans with intelligent speed control and other noise-reducing measures enable low noise emissions from the external units of only 30 dB(A) at a distance of four meters. This means that the heat pump can barely be heard. The emission guidelines based on the German Technical Instructions on Noise Abatement in residential areas during daytime and nighttime operation remain within the permitted maximum range, even on small properties.

Viessmann has developed Hydro AutoControl to save time when installing the systems. The patented hydraulic system ensures that the heat pumps will adapt to almost all available heating systems during the modernization process and eliminates the kind of time-consuming installation work that other heat pumps require. For example, the system already comes with an integrated and connected heating water buffer cylinder for providing defrosting energy. A flow rate sensor is also integrated and works with the bypass valve to maintain optimum circulation rates.

Energy Management system provides transparency regarding consumption and costs

Be it at the same time as the heat pumps are being installed or at a later date – Vitocal 250-A and Vitocal 252-A can be combined with the  Vitovolt  photovoltaic modules and the  Vitocharge VX3  electricity storage system at any time. That means the heat pumps can run on self-generated green electricity for much of the day. All system components are connected seamlessly with Viessmann’s digital services via the  Viessmann One Base  platform. This enables convenient operation by users via their smartphones and the  ViCare  app, as well as straightforward commissioning, comprehensive system monitoring and remote maintenance by specialist companies using the  ViGuide  service tool.

The  Viessmann Energy Management  system, which has been integrated into the ViCare app, records all energy flows between the heat pump, electricity storage system and any wallbox for electric vehicles and shows the data in a graphic on the smartphone or tablet display. This gives users a constant source of transparent information on energy generation and consumption. Most importantly, however, the control systems for the heat pump module and the electricity storage system make use of the Energy Management system to ensure efficient operation.

Benefits for trade partners

• With a flow temperature of 70 °C (65 °C at -15 °C), ideally suited for modernization projects and DHW generation
• Installation as easy as a wall-mounted gas boiler
• Around 50% fewer components to install than conventional units
• No need to maintain minimum flow rate, circulation volume or water temperature during commissioning
• Service link enables fast responses to malfunctions
• Only one control and service app for all heat generators

Benefits for users

• Very quiet operation, 30 dB(A) at a 4 m distance (Super Silent) means the heat pump can barely be heard
• Reliable operation and superior efficiency (OptiPerform)
• Low operating costs thanks to high efficiency, COP (coefficient of performance) based on EN 14511: up to 5.4 (for A7/W35)
• Cooling using the “active cooling“ function
• Protects the climate and environment (Climate Protect+++)
• Faster responses to malfunctions guaranteed (service link)
• Convenient control via ViCare app
• Integrated Energy Management system for transparent information on energy consumption and costs

Technical specifications

• Output: 2.1 to 18.5 kW (cascaded up to 37 kW)
• Maximum flow temperature: 70 °C (based on an outside temperature of as low as -10 °C)
• COP value (coefficient of performance) based on EN 14511: up to 5.4 (for A7/W35)
• Dimensions of external unit (length x width x height):
• 600 x 1144 x 841 mm (2.1 to 8.0 kW)
• 680 x 1144 x 1382 mm (5.3 to 18.5 kW)
• Weight:
• 162 kg (2.1 to 8.0 kW)
• 253 kg (5.3 to 18.5 kW)
• Energy efficiency category: A+++

Vitoset climate-control ceiling: panel heating and cooling for new builds and modernization projects

The GeoClimaDesign system, a new member of the Vitoset family, is suitable for new and existing buildings alike. Particularly in older buildings, the Vitoset climate-control ceiling offers the advantage that it is much easier to install than conventional floor heating systems. This means that the climate-control ceiling opens up new options for the use of heat pumps in many older buildings that were previously considered less suitable for this type of heat generation, for example, efficient cooling in the summer and increased efficiency in the winter.

Silent, dust-free and draft-free heat transmission

The Vitoset climate-control ceiling is silent, dust-free and draft-free, ensuring maximum climate comfort within the home. It combines two functions in one system – heating and cooling. This saves customers from having to invest in two separate solutions for air conditioning.

The new climate-control ceiling in Viessmann’s portfolio consists of lightweight and flat BLUEMAT capillary tube mats and a coordinated pipe system featuring distributors, as well as a dew-point-based heating/cooling control system. The arrangement of the capillary tubes close to each other and the comparatively small differences between the ambient air temperature and the temperature in the system’s water circuit ensure high transmission performance.

Simple installation

The system is installed on the ceiling, saving space. Quick and straightforward installation in a suspended drywall ceiling is standard practice. The hydraulic connection station, which is already included in the package, means that the Vitoset climate-control ceiling can then be easily connected to the Vitocal heat pumps and hybrid Viessmann devices.

Concrete core activation in large residential complexes

In large residential complexes, the climate-control ceiling can also be used for concrete core activation. This is achieved by ensuring that the BLUEMAT capillary tube mats are already cast into the pre-cast ceiling in the concrete factory.

Benefits for trade partners

• Lightweight and low installation height
• For drywall, acoustic and clay plaster ceilings
• Complete assembly kit, planned individually for each project

Benefits for users

• Alternative to floor heating
• Suitable for renovation projects and new builds
• More efficient heat pump thanks to optimum flow temperatures for heating and cooling (increase in the coefficient of performance)
• Cooling can use 100 percent geothermal energy
• No need for radiators or air conditioners
• Improved look of the room
• Eligible for subsidies in existing buildings in conjunction with a heat pump or gas-heat pump hybrid heating system

Technical specifications

• Output: up to 75 W/m²
• Material: polypropylene BLUEMAT capillary tube mats, built to project specifications
• Overall height: at least 50 mm
• Number of control circuits: up to 12 per distributor

Delivery date

The Vitoset climate-control ceilings (GeoClimaDesign system) are already available for delivery.