Vaillant Heat Pumps In Brief
Vaillant are a well-known European heating brand. Many UK customers know Vaillant for the excellence of their boilers, but they have branched-out to be a major supplier of heat pumps and share a significant slice of the domestic market.
Although heat pumps can obtain their energy from air, ground or water, most household heating appliance suppliers concentrate on air-source heat pumps. Vaillant is one of the few residential heat pump suppliers that has a range of different heating systems so the customer can choose the setup that is best for their home.
The products are especially quiet in operation, which is important for users: most have been awarded the ‘Quiet Mark’ for their noise reduction low-decibel sound performance. Some of their most critical components have been made corrosion resistant, which is important in the UK climate.
Vaillant Heat Pump Models
The brand has four main types in its heat pump range, all of which will help reduce a household’s energy consumption.
- The Vaillant flexoTHERM air source heat pump, which is the most conventional offering for residential use.
- The Vaillant aroTHERM hybrid heat pump system, which combines an air-to-water heat pump with a conventional boiler: it always uses the cheapest source of energy, but with the reliability of a standard boiler as an alternate, and backup, form of heating.
- The Vaillant flexoTHERM water-source heat pump range is useful for homeowners who have a nearby source of water such as a lake, river or stream. This can be recommended for rural sites which can utilise this stable input of dependable energy.
- The Vaillant flexoTHERM multi-source heat pump is outstanding in that it can utilise air, water or ground-source for its energy input.
Vaillant previously offered a range of geoTHERM ground-source heat pumps for home use, but these have been discontinued. Ground-source heat pumps are efficient, but the heating element needs to be dug into the ground to accommodate the ground loops, which limits the locations that it can be installed in and increases installation costs.
Vaillant heat pumps are certified by the Microgeneration Certification Scheme (MCS), a national quality assurance scheme that ensures high quality standards in renewable energy technologies. It also means that homeowners can access various grants and funding to help reduce Vaillant heat pump cost. Warranties range from five to seven years duration.
Vaillant Heat Pump Costs
Air source heat pumps will be the most commonly used type purely because most outdoor spaces are insufficient to accommodate the necessary ground loops for a ground source system. For the most basic of air source heat pumps you might expect to pay around £3,500 to £4,000, while larger systems might cost as much as £15,000. You would also need to add the installation costs to these amounts which can easily double the costs depending on the complexity of the installation and the upgrades (usch as radiators, underfloor heating, pipework etc) required.
Typical costs of some common Vaillant heat pump models:
| Heat pump model | Type | Size | Cost |
| Vaillant aroTHERM plus | Air source | 3.5kW | £3,500 |
| Vaillant aroTHERM plus | Air source | 7kW | £6,500 |
| Vaillant aroTHERM Split | Air source | 5kW | £4,000 |
| Vaillant aroTHERM Split | Air Source | 10kW | £6,000 |
| Vaillant flexoTHERM | Ground/water source | 5kW | £6,000 |
| Vaillant flexoTHERM | Ground/water source | 19kW | £8,000 |
Vaillant Heat Pump Specifications
The aroTHERM plus air-to-water heat pump range
- Five different models from 3.5kW to 12kW.
- Environmentally friendly and future-proof.
- Future-proof thanks to the most cutting-edge heat pump technology with natural refrigerant, reducing your carbon footprint.
- High energy efficiency class.
- Very quiet operation – can even be used in densely built-up terraced housing estates.
aroTHERM plus air-to-water 12kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 58 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM plus air-to-water 10kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 58 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM plus air-to-water 7kW
| Dimensions (W x H x D mm) | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 53 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM plus air-to-water 5kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 51 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM plus air-to-water 3.5kW
| Dimensions (W x H x D mm) | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 51 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
The aroTHERM split air source heat pump range
Enhances the freely available heat from the outside air to heat the home, which can help to reduce resident’s fuel bills and carbon footprint. It comes in two modules: an indoor wall-mounted unit and an outdoor unit.
Up to seven years parts and labour warranties, when installed by a Vaillant partner.
Available in five different sizes of heat output.
aroTHERM Split 12kW
| Dimensions outdoor unit (H x W x D mm) | 1480 x 1100 x 450 |
| Dimensions indoor unit (H x W x D mm) | 770 x 440 x 350 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 56 |
| Maximum hot water flow temperature °C | 62 |
| Global warming potential according to Regulation (EU) No. 517/2014 | 2,088 |
aroTHERM Split 10kW
| Dimensions outdoor unit (H x W x D mm) | 1480 x 1100 x 450 |
| Dimensions indoor unit (H x W x D mm) | 770 x 440 x 350 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 56 |
| Maximum hot water flow temperature °C | 62 |
| Global warming potential according to Regulation (EU) No. 517/2014 | 2,088 |
aroTHERM Split 7kW
| Dimensions outdoor unit (H x W x D mm) | 965 x 1100 x 450 |
| Dimensions indoor unit (H x W x D mm) | 770 x 440 x 350 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 55 |
| Maximum hot water flow temperature °C | 62 |
| Global warming potential according to Regulation (EU) No. 517/2014 | 2,088 |
aroTHERM Split 5kW
| Dimensions outdoor unit (H x W x D mm) | 765 x 1100 x 450 |
| Dimensions indoor unit (H x W x D mm) | 770 x 440 x 350 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 54 |
| Maximum hot water flow temperature °C | 62 |
| Global warming potential according to Regulation (EU) No. 517/2014 | 2,088 |
aroTHERM Split 3.5kW
| Dimensions outdoor unit (H x W x D mm) | 765 x 1100 x 450 |
| Dimensions indoor unit (H x W x D mm) | 770 x 440 x 350 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 53 |
| Maximum hot water flow temperature °C | 62 |
| Global warming potential according to Regulation (EU) No. 517/2014 | 2,088 |
The aroTHERM air-to-water heat pump range
The pump harnesses natural resources, so it can help to save money on home fuel bills and reduce carbon emissions. Homeowners can benefit from a range of warranties of up to 7 years parts and labour when installed by a renewable partner. There are four sizes of heat output available, so it’s a good solution for replacing the current heating system in most kinds of property.
The aroTHERM range 15kW
| Dimensions (H x W x D mm) | 1375 x 1103 x 463 |
| ErP at 35°C | A++ |
| ErP at 55°C | A+ |
| Sound power level dB(A) | 66 |
| Maximum hot water flow temperature °C | 63 |
The aroTHERM range 11kW
| Dimensions (H x W x D mm) | 975 x 1103 x 463 |
| ErP at 35°C | A+ |
| ErP at 55°C | A+ |
| Sound power level dB(A) | 66 |
| Maximum hot water flow temperature °C | 63 |
The aroTHERM range 8kW
| Dimensions (H x W x D mm) | 975 x 1103 x 463 |
| ErP at 35°C | A++ |
| ErP at 55°C | A++ |
| Sound power level dB(A) | 60 |
| Maximum hot water flow temperature °C | 63 |
The aroTHERM range 5kW
| Dimensions (H x W x D mm) | 834 x 970 x 408 |
| ErP at 35°C | A++ |
| ErP at 55°C | A+ |
| Sound power level dB(A) | 58 |
| Maximum hot water flow temperature °C | 60 |
The aroTHERM Plus hybrid heat pump system
Hybrid heating solution which combines aroTHERM air-to-water heat pump with a traditional boiler. Unique triVAI technology to ensure the most efficient energy source is always used. Great first step into a renewable and sustainable heating system for your home and can be combined with a hot water cylinder.
aroTHERM Plus hybrid 12kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 58 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM Plus hybrid 10kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 58 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM Plus hybrid 7kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 53 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM Plus hybrid 5kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 51 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
aroTHERM Plus hybrid 3.5kW
| Dimensions (W x H x D) mm | 1,100 x 765 x 449 |
| Sound power, EN 12102, EN 14511 LWA, A7/W35 dB(A) | 51 |
| Energy efficiency class 35°C band | A+++ |
| Energy efficiency class 55°C band | A++ |
| Global warming potential | 3 |
flexoTHERM air source heat pump
The heat pump harnesses natural energy from the air, which means it can help to save money on fuel bills and reduce the home’s carbon footprint. Homeowners can benefit from a range of warranties of up to 7 years parts and labour when installed by a Vaillant renewable partner.
There are a range of heat outputs available, so it’s a good solution for homes that have a 400V power supply.
flexoTHERM 5kW 400V
| Product dimensions (H x D x W) mm | 1185 x 600 x 595 |
| aroCOLLECT dimensions (H x D x W) mm | 1256 x 785 x 1192 |
| Weight, with packaging kg | 155 |
| Weight, without packaging kg | 145 |
| Sound power level A7/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 40.3 |
| Energy-related Products at 35°C* band | A+++ |
| Energy-related Products at 55°C* band | A+++ |
flexoTHERM 8kW 400V
| Product dimensions (H x D x W) mm | 1185 x 600 x 595 |
| aroCOLLECT dimensions (H x D x W) mm | 1256 x 785 x 1192 |
| Weight, with packaging kg | 170 |
| Weight, without packaging kg | 160 |
| Sound power level A7/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 45.8 |
| Energy-related Products at 35°C* band | A+++ |
| Energy-related Products at 55°C* band | A+++ |
flexoTHERM 11kW 400V
| Product dimensions (H x D x W) mm | 1185 x 600 x 595 |
| aroCOLLECT dimensions (H x D x W) mm | 1256 x 785 x 1192 |
| Weight, with packaging kg | 178 |
| Weight, without packaging kg | 168 |
| Sound power level A7/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 44.4 |
| Energy-related Products at 35°C* band | A+++ |
| Energy-related Products at 55°C* band | A+++ |
flexoTHERM 15kW 400V
| Product dimensions (H x D x W) mm | 1185 x 600 x 595 |
| aroCOLLECT dimensions (H x D x W) mm | 1256 x 785 x 1192 |
| Weight, with packaging kg | 185 |
| Weight, without packaging kg | 176 |
| Sound power level A7/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 48.7 |
| Energy-related Products at 35°C* band | A+++ |
| Energy-related Products at 55°C* band | A+++ |
flexoTHERM 19kW 400V
| Product dimensions (H x D x W) mm | 1185 x 600 x 595 |
| aroCOLLECT dimensions (H x D x W) mm | 1256 x 785 x 1192 |
| Weight, with packaging kg | 197 |
| Weight, without packaging kg | 187 |
| Sound power level A7/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 48.1 |
| Energy-related Products at 35°C* band | A+++ |
| Energy-related Products at 55°C* band | A+++ |
flexoTHERM water source heat pump
The heat pump harnesses natural energy from a water source, which can help to save money on home fuel bills and reduce the building’s carbon footprint. Homeowners can benefit from a range of warranties of up to 7 years parts and labour when installed by a Vaillant renewable partner. There are a range of heat outputs available, so it’s a good solution for homes that have a local water source, such as a lake, river or stream.
flexoTHERM water 5kW 230V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 43.3 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 8kW 230V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 46.9 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 11kW 230V
| Dimensions (H x W x D) mm | 183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 50.0 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 5kW 400V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 41.2 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 8kW 400V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 47.9 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 11kW 400V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 45.0 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 15kW 400V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 49.9 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
flexoTHERM water 19kW 400V
| Dimensions (H x W x D) mm | 1183 x 595 x 600 |
| fluoCOLLECT dimensions (H x D x W) mm | 720 x 291 x 733 |
| Sound power level B0/W35 EN 12102/EN 14511 LWI in heating mode dB(A) | 50.6 |
| Energy-related Products at 35˚C* band | A+++ |
| Energy-related Products at 55˚C* band | A+++ |
The flexoTHERM multi-source heat pump
A smart and flexible multi-source heating system that uses renewable heat sources from the ground, water or air. The heat pump can be configured to work with either air, ground, or water sources.
The heat pump comes in different sizes of heat output to suit every property, with 5, 8, 11, 15 and 19kW models available. It’s simple to install, and features intelligent weather compensating controls and Wi-Fi connectivity for remote operation.
flexoTHERM multi-source 5kW 230V
| Product dimensions (H x D x W) mm | 1183 x 595 x 600 |
| Sound power level B0/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 43.8 |
| Energy-related Product 35°C* band | A+++ |
| Energy-related Product 55°C* band | A+++ |
flexoTHERM multi-source 8kW 400V
| Product dimensions (H x D x W) mm | 1183 x 595 x 600 |
| Sound power level B0/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 42.4 |
| Energy-related Product 35°C* band | A+++ |
| Energy-related Product 55°C* band | A+++ |
flexoTHERM multi-source 11kW 400V
| Product dimensions (H x D x W) mm | 1183 x 595 x 600 |
| Sound power level B0/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 45.2 |
| Energy-related Product 35°C* band | A+++ |
| Energy-related Product 55°C* band | A+++ |
flexoTHERM multi-source 15kW 400V
| Product dimensions (H x D x W) mm | 1183 x 595 x 600 |
| Sound power level B0/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 45.2 |
| Energy-related Product 35°C* band | A+++ |
| Energy-related Product 55°C* band | A+++ |
*A+++ is achievable when paired with Vaillant’s VRC 700/ VRC 700f system control.
flexoTHERM multi-source 19kW 400V
| Product dimensions (H x D x W) mm | 1183 x 595 x 600 |
| Sound power level B0/W35 | |
| EN 12102/EN 14511 LWI in heating mode dB(A) | 48.4 |
| Energy-related Product 35°C* band | A+++ |
| Energy-related Product 55°C* band | A+++ |
Vaillant Company Overview:
Founded in Germany in 1874, the group of companies now spans Europe with manufacturing sites globally, including Vaillant UK in Derbyshire, where the company’s aroTHERM heat pumps are produced. Unusually for a modern technology company, it remains family-owned. Worldwide it has over 17,000 employees on 10 sites, bringing in €3.7 billion in revenue each year, making it the second-largest heating technology manufacturer in Europe.
Vaillant Heat Pump Pros and Cons
| Pros | Cons |
| Good range of products | Can involve complex installation |
| Reliable heat pumps | Higher costs than some systems especially for ground source heat pumps |
| More flexible than competitor offerings | Can require upgrade to radiators and pipework |
| ‘Quiet Mark’ accreditation | Some units require space for an outdoor unit and indoor hot water cylinder |
| Adapted specifically for British climate | Limitations of COP information provided by companion app |
Vaillant Heat Pump FAQs
Q: How does a Vaillant heat pump work?
A: By using ambient energy embedded in the surroundings, Vaillant heat pumps can extract this pollution-free source of energy and then use it to heat water (for example) and pipe it around your home to your radiators or underfloor heating. The heat pump does require some electricity to power the heat pump, but generally this is 75% more efficient than other forms of heating, potentially saving a lot on bills.
Q: Can you connect a Vaillant heat pump to existing radiators?
A: Heat pumps can often be attached to existing radiators, so it is possible that some Vaillant heat pumps can be retrofitted into an existing home-heating system without much disruption. Much will depend on the size of the existing radiators as heat pumps operate at lower flow temperatures than traditional gas boilers, so require large or ‘oversized’ radiators to function effectively and make a significant difference to energy bills.
Q: How long do heat pumps typically last?
A: Modern heat pump units typically last for around 20-25 years before they need replacing and Vaillant heat pump are no exception to this. They have few parts that can wear out, compared to traditional gas boilers, so are considered more reliable: traditional gas boiler life expectancy tends to be around 10-12 years.
Q: Is there funding available to reduce the cost of installing a Vaillant heat pump?
A: Currently there are grants available for heat pump installation under the Boiler Upgrade Scheme and this is aimed at low income energy inefficient homes to help them reduce energy bills. You do not have to be receiving benefits to receive funding, so find out if you are eligible by enquiring with Heat Pumps UK today.
Vaillant Heat Pump Summary
Vaillant heat pumps are among the most flexible types available to residential customers and have a great track record of reliability and high efficiency heat pump performance. They can usually be set up to provide both heat and domestic hot water for the home. This makes them a good product to install as a replacement for traditional heating systems such as an old gas boiler.
There are downsides, depending on the exact model and purpose: ground and water-source heat pumps do have more extensive and complex installations than air-source heat pumps so that is reflected in their costs, although these types do also have advantages to balance that out.
While Vaillant heat pump prices can be more expensive compared to some of their competitors, they are a market-leading company and their heat pumps can be recommended as a central heating system for most situations. With funding of up to £7,500 potentially available to eligible households from government-backed schemes such as the Boiler Upgrade Scheme, a new heat pump could be a more affordable prospect for many people.
