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About ViessmannViessmann Heat Pumps1. Vitocal 150-A2. Vitocal 150-A Hybrid3. Vitocal 200-A4. Vitocal 250-A PROHow Efficient Are Viessmann Heat Pumps?What Size Viessmann Heat Pump Do I Need?How Do Viessmann Heat Pumps Compare to Other Brands?Is a Viessmann Air Source Heat Pump Right for Your Home?Viessmann Air Source Heat Pumps FAQs
About ViessmannViessmann Heat Pumps1. Vitocal 150-A2. Vitocal 150-A Hybrid3. Vitocal 200-A4. Vitocal 250-A PROHow Efficient Are Viessmann Heat Pumps?What Size Viessmann Heat Pump Do I Need?How Do Viessmann Heat Pumps Compare to Other Brands?Is a Viessmann Air Source Heat Pump Right for Your Home?Viessmann Air Source Heat Pumps FAQs
If you’re considering a heat pump for your home, Viessmann is a brand worth knowing. The manufacturer offers a range of air source heat pumps designed to provide efficient heating and hot water while using electricity instead of gas or oil.
In this Viessmann air source heat pump review, we look at the brand’s key models, features, efficiency and other important factors to consider before you buy.
We’ll also compare Viessmann heat pumps with other leading brands and explain what you need to know about installation, performance and suitability for your home. This will help you decide whether an air source heat pump could be the right choice for your home.
Could a heat pump be right for your home? Complete the form below to get a heat pump quote from one of our specialists:
Viessmann is a German heating manufacturer with more than 100 years of experience in the industry. The company was founded in 1917 as a heating technology manufacturer and has since expanded into cooling, hot water and renewable energy solutions.
For many years, Viessmann has been known for its range of domestic boilers. Its current UK range includes gas boilers such as the Vitodens 050-W, 100-W and 200-W, alongside other heating systems designed for different types of homes.
However, Viessmann now offers more than traditional boiler systems. Its product range includes air source and ground source heat pumps, solar technology, electric heating and other renewable energy solutions.
This shift towards renewable heating has made Viessmann a well-known name in the UK heat pump market. Its air source heat pump range is designed to use energy from the air outside to provide heating and hot water for your home.
Today, Viessmann Climate Solutions is part of Carrier and continues to develop heating and renewable energy technologies for homes and businesses.
| Viessmann Heat Pump | Available Sizes | Key Features | Best Suited For |
|---|---|---|---|
| Vitocal 150-A | 4kW, 6kW, 8kW, 10kW, 13kW, 16kW | R290 natural refrigerant, up to 70°C flow temperature, A+++ energy efficiency, integrated 190-litre hot water cylinder, ViCare app connectivity | New builds and retrofit homes, with higher-output models suitable for some renovation projects |
| Vitocal 150-A Hybrid | Up to 36kW when combined with an external heat generator | R290 natural refrigerant, up to 70°C flow temperature, hybrid operation, integrated buffer tank, ViCare app connectivity | Homeowners modernising their heating system who want to combine a heat pump with an existing boiler or heat generator |
| Vitocal 200-A | 6kW, 8kW, 10kW, 12kW | R290 natural refrigerant, A+++ energy efficiency, compact design, smart controls, ViCare app connectivity, compatible with radiators and underfloor heating | New builds and retrofit homes, including semi-detached and detached properties and block of flats |
| Vitocal 250-A PRO | Up to 39.5kW per unit; up to 158kW with four units | R290 natural refrigerant, up to 70°C flow temperature, heating, cooling and hot water, cascade operation, online monitoring, building management system connectivity | Larger residential and commercial properties, including block of flats and other buildings with high heating demands |
Available Sizes: 4kW, 6kW, 8kW, 10kW, 13kW, 16kW
Key Features:
Uses low-GWP R290 natural refrigerant
Flow temperatures of up to 70°C
Suitable for heating, cooling and domestic hot water
Integrated 190-litre hot water cylinder
A+++ energy efficiency
ViCare app connectivity
Integrated energy management system
5-year standard warranty, extendable to 10 years
The Viessmann Vitocal 150-A is an air-to-water heat pump designed to provide heating and hot water for residential properties. It uses heat from the outside air and transfers it into the home, providing an alternative to traditional gas or oil heating.
The system uses a monobloc design, meaning the main refrigeration components are contained within the outdoor unit. Viessmann offers lower-output versions for new-build homes, while the larger 10kW, 13kW and 16kW models can reach flow temperatures of up to 70°C, making them suitable for some renovation and boiler replacement projects.
The Vitocal 150-A uses R290 (propane) refrigerant, which has a particularly low global warming potential. It can also achieve a coefficient of performance (COP) of up to 5.2 under specific test conditions, helping to keep electricity use and running costs lower when the system is operating efficiently.
The system includes a 190-litre integrated domestic hot water cylinder, as well as components such as a circulation pump and instantaneous heating water heater. This provides a complete heating and hot water solution without requiring a separate hot water cylinder.
Homeowners can also connect the Vitocal 150-A to the ViCare app, allowing them to control their heating remotely and view information about energy consumption. The system can also provide active cooling during warmer months when configured for this function.
Available Sizes: Up to 36kW when combined with an external heat generator
Key Features:
Monobloc air-to-water heat pump design
Uses low-GWP R290 natural refrigerant
Flow temperatures of up to 70°C at outdoor temperatures down to -10°C
Designed for hybrid operation with an existing heating system
Suitable for heating, cooling and domestic hot water
Integrated buffer tank and overflow valve
ViCare app connectivity
5-year standard warranty, extendable to 10 years
The Viessmann Vitocal 150-A Hybrid is an air-to-water heat pump designed to work alongside an existing heating system. Rather than completely replacing your current heat source, it can be connected to an external heat generator with an output of up to 36kW, allowing both systems to work together.
This makes the Vitocal 150-A Hybrid particularly suitable for homeowners looking to modernise their heating system without removing their existing boiler or other heat generator. The heat pump can provide efficient heating when conditions are suitable, while the existing system can provide additional heat when required.
The system uses R290 (propane) refrigerant, which has a particularly low global warming potential. It can deliver flow temperatures of up to 70°C at outdoor temperatures down to -10°C, making it suitable for a range of modernisation and retrofit projects.
The Vitocal 150-A Hybrid can provide space heating, cooling and domestic hot water. Its monobloc indoor unit includes the heat pump controls, a high-efficiency circulation pump and safety components, while an integrated buffer tank helps support the operation of the heating system.
Homeowners can also use the ViCare app to operate the system and monitor information about energy consumption and costs. An integrated energy management system provides additional insight into how the system is being used.
Available Sizes: 6kW, 8kW, 10kW, 12kW
Key Features:
Uses low-GWP R290 natural refrigerant
A+++ energy efficiency rating
Suitable for new-build and retrofit properties
Works with radiators and underfloor heating
Compact, space-saving design
Suitable for heating and hot water
Smart controls and ViCare app connectivity
Can integrate with existing heating systems and third-party components
The Viessmann Vitocal 200-A is an air-to-water heat pump designed to provide efficient heating and hot water for homes. It is available in outputs from 6kW to 12kW, making it suitable for a range of property sizes and heating requirements.
The system can be used in both new-build and retrofit properties, and is designed to work with different types of heating systems, including radiators and underfloor heating. It can also provide reliable heating and hot water when higher flow temperatures are required.
The Vitocal 200-A uses R290 (propane) refrigerant, which has a very low global warming potential of 0.02. It can achieve an energy efficiency rating of up to A+++, helping to reduce energy consumption when operating under suitable conditions.
Its compact design allows for flexible installation where space is limited. The system can also be integrated with existing heating equipment and compatible third-party components, making it a flexible option for homeowners upgrading their heating system.
The Vitocal 200-A also features smart controls and ViCare app connectivity, allowing homeowners to manage their heating from a single app. The system can optimise energy flows to support efficient heating and cooling, while installers can remotely monitor its operation and performance.
Available Sizes: Up to 39.5kW per unit, with up to four units in a cascade providing up to 158kW
Key Features:
Provides heating, cooling and domestic hot water
Uses low-GWP R290 natural refrigerant
Flow temperatures of up to 70°C
Can operate alongside an existing heat generator
Up to 39.5kW heating output from a single unit
Up to 158kW output through a cascade arrangement
Compact, sound-insulated outdoor unit
Three-phase power supply
Modbus TCP/IP and BACnet/IP connectivity for building management systems
Online system monitoring
Designed for straightforward servicing
The Viessmann Vitocal 250-A PRO is a commercial air source heat pump designed for larger properties and higher heating demands. It can provide heating, cooling and domestic hot water from a single system, making it suitable for block of flats, larger residential developments and commercial properties.
The system can provide up to 39.5kW of heating output from a single unit. For buildings with greater heating requirements, up to four units can be connected in a cascade arrangement, providing a combined output of up to 158kW while using just one indoor unit.
With flow temperatures of up to 70°C, the Vitocal 250-A PRO is also designed with modernisation projects in mind. It can operate alongside an existing heat generator, allowing it to be incorporated into an existing heating system where required.
The heat pump uses R290 natural refrigerant and features a variable-output scroll compressor and electronic expansion valves. These components allow the system to adjust its output according to demand, helping to maintain efficient operation and manage energy consumption.
Despite its high output, the Vitocal 250-A PRO has a compact outdoor design and sound-insulated casing. Its low sound emissions make it suitable for installation in more densely populated areas, while integrated Modbus TCP/IP and BACnet/IP interfaces allow it to connect to building management systems.
The system also includes online monitoring and accessible components to make servicing easier. A three-phase power supply is used, reflecting the higher electrical requirements of this type of commercial heating system.
Related Reading:
Air source heat pumps can be a highly efficient way to heat your home. Rather than generating heat by burning fuel, they use electricity to extract heat energy from the air outside and transfer it into your home.
The efficiency of an air source heat pump is often shown through its Coefficient of Performance (COP). This indicates how much heat the system can produce for each unit of electricity it uses. For example, a COP of 4 means the system produces around 4kW of heat for every 1kW of electricity used under the relevant test conditions.
However, a heat pump's efficiency can change depending on the conditions it operates in. Outdoor temperature, the required flow temperature and the condition of your home can all affect how efficiently the system performs.
A well-insulated home can also help an air source heat pump operate more efficiently by reducing the amount of heat needed to maintain a comfortable indoor temperature. Lower flow temperatures can also improve efficiency, which is one reason heat pumps are often paired with appropriately sized radiators or underfloor heating.
Many modern air source heat pumps achieve high energy efficiency ratings, with some models reaching A+++ under the relevant testing conditions. However, the efficiency rating of a particular system should not be viewed in isolation, as real-world performance depends on the installation and how the system is used.
Choosing the right air source heat pump size is important for getting reliable heating while keeping energy use under control. Heat pumps are available in different power outputs, usually measured in kilowatts (kW), as discussed above.
The required output is not determined by your home's floor area alone. A professional installer, such as Glow Green, should carry out a heat loss calculation to establish how much heat your property needs to stay warm during colder weather.
Several factors can affect the size of heat pump required, including the size and layout of your home, insulation levels, windows, property age and the type of heating system already installed.
Your hot water requirements should also be considered. The number of people living in your home and your typical hot water usage can influence the overall system design and the size of the hot water cylinder required.
It is important not to assume that a larger heat pump will provide better performance. An oversized system may cycle on and off more frequently, while an undersized system may struggle to provide enough heat during colder periods.
A qualified heat pump installer, such as Glow Green, can assess your property and recommend an appropriate system size based on its heat loss and heating requirements. This helps ensure your air source heat pump is correctly matched to your home and can operate efficiently throughout the year.
Viessmann is one of several established manufacturers offering air source heat pumps in the UK. Although heat pumps from different manufacturers work in a similar way, there can be important differences between models, including their refrigerant, power output, flow temperature, system design and smart controls.
Comparing Viessmann with other well-known manufacturers can help you understand how the different systems vary. Here are some of the key differences to consider:
Both Viessmann and LG offer air-to-water heat pumps for residential properties, with a choice of models and power outputs. LG heat pumps include THERMA V Monobloc, Split and Hydrosplit systems, while Viessmann offers models such as the Vitocal 150-A and Vitocal 200-A.
Both manufacturers offer systems using lower-GWP refrigerants, including R290 models. However, individual systems differ in areas such as maximum flow temperature, available outputs, controls and installation requirements.
Viessmann and Samsung both manufacture air source heat pumps designed to provide heating and hot water. Samsung heat pumps are available across the EHS range, including Mono and Split systems.
Viessmann's range includes monobloc systems such as the Vitocal 150-A, while Samsung offers several system configurations. Both manufacturers also provide smart controls for compatible systems, although the features and technology used differ between individual models.
Viessmann and Aira take different approaches to supplying heat pump systems. Viessmann manufactures a range of heating and renewable energy products that can be installed by heating professionals, while Aira heat pumps are offered as part of an integrated installation and servicing package.
Viessmann therefore provides a broader range of heating products and heat pump models, while Aira's approach combines its own heat pump technology with installation and ongoing servicing.
The choice between systems will depend on the type of property, heating requirements and installation package being considered.
Both Viessmann and Worcester Bosch have long-established positions in the UK heating market and offer air source heat pumps as an alternative to traditional boiler systems. Worcester Bosch heat pumps include the company's air-to-water heat pump systems, designed to work alongside its wider range of heating products.
Viessmann also offers heat pumps alongside its traditional heating technology. Its range includes R290 systems with flow temperatures of up to 70°C, while Worcester Bosch offers its own selection of heat pump models and system configurations.
Individual specifications should be compared when choosing between the two.
Viessmann and Daikin both have extensive experience in heating and climate technology. Daikin heat pumps include several air-to-water systems designed for residential heating and hot water.
Viessmann's current range includes R290 air source heat pumps, while Daikin offers systems using different refrigerant technologies depending on the model.
There are also differences in power outputs, system design, controls and installation requirements, so comparing specific models is important.
Viessmann and Vaillant are both established heating manufacturers offering air source heat pumps for UK homes. Vaillant heat pumps include the aroTHERM range, while Viessmann's range includes models such as the Vitocal 150-A and Vitocal 200-A.
Both manufacturers offer heat pumps designed for use in new-build and retrofit properties, although the available outputs, refrigerant, flow temperatures and system configurations vary between models.
The suitability of each system will depend on the heating requirements and characteristics of the property.
A Viessmann air source heat pump could be an option if you're looking to replace a gas or oil boiler with an electric heating system. However, choosing a heat pump involves more than simply selecting a manufacturer.
Your property's size, insulation, existing heating system and heat loss will all affect the type and size of heat pump required. Your installer will also need to consider the radiators, pipework and hot water requirements to make sure the system is appropriately designed.
The space available inside and outside your property is another consideration. The outdoor unit needs a suitable location, while indoor components such as the hot water cylinder and controls will also need to be accommodated.
Viessmann offers several heat pump models, from systems designed for individual homes through to larger systems for higher heating demands. Other manufacturers have their own ranges, with differences in specifications, features and installation requirements.
For this reason, it's worth comparing individual heat pump models rather than choosing based on the manufacturer alone. A qualified heat pump specialist can assess your property, calculate its heating requirements and explain which systems may be suitable.
Thinking about installing a heat pump? Get a heat pump quote from Glow Green. One of our specialists can assess your requirements and discuss the different heat pump options available.
Want to find out if your home is suitable for a heat pump? Read our guide, Is My Home Suitable for a Heat Pump in the UK?, to learn more about the key factors to consider before installation.
A Viessmann heat pump should be checked and maintained regularly to help keep it operating safely and efficiently. The exact servicing requirements can vary depending on the model and installation, so your installer or manufacturer guidance should be followed.
Viessmann designs its air source heat pumps with noise reduction in mind, although the sound level will vary between models and operating conditions. The position of the outdoor unit can also affect how noticeable the noise is, so your installer should consider its location carefully.
Yes, a Viessmann heat pump can be used alongside a solar panel system. Solar panels can generate electricity to help power the heat pump, potentially allowing you to use more of the renewable electricity generated at home. A solar battery can also be considered to store excess solar energy for later use.
Compatible Viessmann heat pumps can be connected to the ViCare app, allowing homeowners to manage their heating remotely. Depending on the system, the app can provide access to heating controls and information about the system's energy use.
Viessmann heat pump warranties can vary depending on the model, installation and warranty terms. Some systems are supplied with a standard five-year warranty, with the option to extend this to 10 years when the relevant conditions are met.
