The best air source heat pumps available in the UK right now are the:
- Vaillant aroTHERM Plus
- Viessmann Vitocal
- Daikin Altherma 3H HT
- Mitsubishi Ecodan
- Samsung EHS Mono HT Quiet
- Panasonic Aquarea
- LG Therma V
- Aira Heat Pump
- Octopus Energy Cosy 6 and 9
- Grant Aerona³ R32
- MasterTherm UK BoxAir Inverter
Each excel in different areas from efficiency and noise levels to value for money, smart tariff integration and cold-weather performance.
Choosing the right heating system for your home is one of the biggest decisions you will make as a property owner.
Whether you are in Maidstone, Canterbury, Folkestone, Tunbridge Wells or anywhere else across Kent or the South East, this guide breaks down everything you need to know about the top models available, how to choose the right one, and how to take advantage of the generous government grants currently on offer.
11 Best Air Source Heat Pumps: Quick Overview
Here is a quick overview of the 11 best air source heat pumps at a glance, followed by individual in-depth reviews to help you make the most informed decision for your property.
| Heat Pump Model | Best For | Power Output | SCOP | Approx. Installed Cost (before grant) |
| Vaillant aroTHERM Plus | Best overall | 3.5 kW to 12 kW | Up to 5.03 | £10,000 to £15,000 |
| Viessmann Vitocal | Most efficient | 4.2 kW to 16 kW | Up to 5.0 | £10,000 to £18,000 |
| Daikin Altherma 3H HT | Best for older homes / cooler climates | 14 kW to 18 kW | A+++ rated | £12,000 to £20,000 |
| Mitsubishi Ecodan | Best budget-friendly option | 5 kW to 14 kW | A+++ rated | £8,000 to £14,000 |
| Samsung EHS Mono HT Quiet | Quietest model | 5 kW to 16 kW | A+++ rated | £9,000 to £15,000 |
| Panasonic Aquarea | Best smart technology | 3 kW to 16 kW | Up to 5.12 | £9,000 to £15,000 |
| LG Therma V | Best value for money | 5 kW to 16 kW | Up to 5.0 | £8,000 to £14,000 |
| Aira Heat Pump | Best warranty and comfort guarantee | 6 kW to 12 kW | Up to 4.7 | £14,229 to £18,500 |
| Octopus Energy Cosy 6 & 9 | Best for smart tariff integration | 5.2 kW to 8.7 kW | Up to 3.9 | £11,959 to £12,000 |
| Grant Aerona³ R32 | Best for larger UK homes and cold-climate reliability | 6 kW to 17 kW | Up to 5.4 | £9,000 to £16,000 |
| MasterTherm UK BoxAir Inverter | Best for flexible multi-zone heating | 2 kW to 30 kW | Up to 4.92 | £10,000 to £17,000 |
Installed costs shown before the £7,500 Boiler Upgrade Scheme grant, which can significantly reduce your upfront investment.
The 11 Best Air Source Heat Pumps: Reviewed By Our Engineers
Below are the 11 best ASHPs reviewed by our engineers at Guscott Heating. Their years of hands-on experience installing and maintaining these exact models across homes throughout Kent and the South East means every review here is grounded in real fitting work, not just manufacturer brochures, giving you a genuinely reliable basis for comparing your options.
1. Vaillant aroTHERM Plus – Best Overall Air Source Heat Pump
The Vaillant aroTHERM Plus is widely regarded as the best overall air source heat pump for UK homes, combining outstanding efficiency, eco-friendly refrigerant, and whisper-quiet operation that makes it a standout choice for residential properties.
| Category | Summary |
| Efficiency | SCOP up to 5.03, R290 refrigerant with GWP of just 3 |
| Performance and Reliability | Trusted European brand, sensoCOMFORT smart control, reliable in UK winters |
| Noise Levels | As low as 28 dB(A) in silent mode; 54 to 60 dB(A) sound power standard |
| Costs | £9,000 to £15,000 installed before grant; £1,500 to £7,500 after grant |
| Best Suited For | 3-bed semi-detached and detached homes, new builds, underfloor heating, radiator retrofits |
| Ratings | Consistently strong reviews for reliability and installer support |
Efficiency
The aroTHERM Plus achieves a peak SCOP of up to 5.03, meaning it produces over five units of heat energy for every single unit of electricity it consumes. It uses R290 (propane) refrigerant, which has a Global Warming Potential (GWP) of just 3, making it one of the most environmentally responsible heat pumps on the market.
Key Features
Available in outputs ranging from 3.5 kW to 12 kW, the aroTHERM Plus suits a wide range of property sizes from small terraced homes to larger four-bedroom detached properties. It delivers flow temperatures up to 75°C, which means it can work effectively with existing standard radiators, not just underfloor heating. It operates in a near-silent mode as low as 28 dB(A), which is quieter than a library.
Performance and Reliability
Vaillant is one of the most trusted heating brands in Europe, and the aroTHERM Plus reflects that reputation. It is compatible with the sensoCOMFORT smart controller, giving homeowners full remote control via a smartphone app. The system performs reliably in typical UK winter temperatures and benefits from Vaillant’s established service and support network.
Costs
Supply-only prices for the outdoor unit range from approximately £3,990 for the 3.5 kW model up to £6,770 for the 12 kW model (trade prices). Fully installed costs typically range from £9,000 to £15,000 before the £7,500 Boiler Upgrade Scheme grant, bringing the net cost down to between £1,500 and £7,500 depending on property size.
After the £7,500 grant is applied, most Kent homeowners can expect to pay between £1,500 and £7,500 for a fully installed system.
Best Suited For
The aroTHERM Plus is particularly well suited to three-bedroom semi-detached and detached homes, new build properties, and those with underfloor heating. Its high flow temperature also makes it a strong retrofit option for older Kent properties still using conventional radiator systems.
Ratings
Vaillant holds a strong reputation on consumer review platforms, with consistently positive feedback around product reliability and installer support in the UK market.
| Pros | Cons |
| Peak SCOP of up to 5.03, among the highest efficiency figures in this guide | Premium pricing compared to budget options like Mitsubishi Ecodan or LG Therma V |
| Uses R290 refrigerant with a very low Global Warming Potential of just 3 | Higher-output models mean higher installed costs before the grant is applied |
| Near-silent operation as low as 28 dB(A) in silent mode | As with most heat pumps, achieving peak SCOP depends on correct sizing and a well-insulated property |
| Flow temperatures up to 75°C, so it works with existing radiators, not just underfloor heating | |
| Wide output range from 3.5 kW to 12 kW suits most Kent property types | |
| Backed by Vaillant’s strong European reputation and established UK service network | |
| Compatible with the sensoCOMFORT app for full remote control |
Read our in-depth review of Vaillant heat pumps.
2. Viessmann Vitocal – Most Efficient Air Source Heat Pump
The Viessmann Vitocal is recognised as one of the most efficient air source heat pumps available in the UK, earning A+++ energy ratings and delivering SCOP values up to 5.0 in real-world conditions.
| Category | Summary |
| Efficiency | SCOP up to 5.0; independently measured SPF 46% above MCS minimum |
| Performance and Reliability | Precision German engineering, reliable to -10°C, gold-plated heat exchanger |
| Noise Levels | Around 46 to 50 dB(A) outdoor sound power, down to 30 dB(A) in low-noise mode (sourced externally) |
| Costs | £10,000 to £18,000 installed before grant; £2,500 to £10,500 after grant |
| Best Suited For | Well-insulated detached homes, efficiency-focused homeowners |
| Ratings | Top pick among independent reviewers including GreenMatch and TopGreenDeals |
Efficiency
In a year-long study conducted between August 2024 and August 2025, seven UK installations of the Vitocal 150-A achieved an average measured seasonal performance factor (SPF) of 4.1, which is 46% higher than the MCS installer threshold of 2.8 required to access the Boiler Upgrade Scheme. The Vitocal 250-A achieves SCOP ratings up to 5.0, reflecting best-in-class German engineering.
Key Features
The Vitocal range features a corrosion-resistant gold-plated heat exchanger designed for long-lasting durability. Available in outputs from 4.2 kW to 16 kW, it covers everything from compact flats to large family homes. The system integrates smoothly with Viessmann’s smart home controls, allowing homeowners to manage energy use remotely.
Performance and Reliability
Viessmann has a reputation for precision-engineered heating products, and the Vitocal lives up to that. It operates effectively even in temperatures as low as -10°C, which is more than adequate for Kent’s relatively mild winters. Its build quality and reliability make it a strong long-term investment.
Costs
Fully installed Vitocal systems typically cost between £10,000 and £18,000 before the £7,500 BUS grant. The net cost after the grant brings it into a competitive range for what is a premium product. After the grant is applied, homeowners can expect to pay between £2,500 and £10,500.
Best Suited For
The Vitocal is an excellent fit for well-insulated detached homes, energy-conscious homeowners looking for maximum efficiency, and properties where long-term running cost savings are the priority.
Ratings
The Viessmann Vitocal is frequently cited as a top pick by independent reviewers including GreenMatch and TopGreenDeals, reflecting its consistently strong performance data across UK installations.
| Pros | Cons |
| SCOP values up to 5.0, reflecting genuinely strong real-world efficiency | One of the more expensive options in this guide, with installed costs reaching up to £18,000 before grant |
| Independently measured performance 46% higher than the MCS minimum threshold in a year-long UK study | Premium pricing may not suit budget-conscious landlords or smaller properties |
| Corrosion-resistant gold-plated heat exchanger built for long-term durability | As a German-engineered premium product, parts and specialist servicing may cost more long term |
| Wide output range from 4.2 kW to 16 kW covers flats through to large family homes | |
| Reliable operation down to -10°C, comfortably within Kent’s climate range | |
| Frequently rated a top pick by independent UK reviewers |
Read our in-depth review of Viessmann heat pumps.
3. Daikin Altherma 3H HT – Best for Older Homes and Cooler Climates
The Daikin Altherma 3H HT is the best air source heat pump for older properties and cooler climates, capable of delivering high flow temperatures and operating reliably in outdoor temperatures as low as -28°C.
| Category | Summary |
| Efficiency | A+++ rated, COP up to 5.43, R32 refrigerant |
| Performance and Reliability | Operates down to -28°C, ideal for older radiator retrofits |
| Noise Levels | 38 dB(A) at 3m standard mode, 35 dB(A) in low sound mode (sourced externally) |
| Costs | £12,000 to £20,000 installed before grant; £4,500 to £12,500 after grant |
| Best Suited For | Period properties, Victorian terraces, large detached homes, former oil-heated rural properties |
| Ratings | Rated a top cold-climate performer by the FMB and EcoWatch |
Efficiency
The Altherma 3H HT carries an A+++ seasonal efficiency rating for heating and uses R32 refrigerant, which strikes a balance between efficiency and lower environmental impact compared to older refrigerants. Its COP performance in controlled conditions reaches up to 5.43, putting it among the top performers for raw heat output per unit of electricity.
Key Features
The standout feature of the Altherma 3H HT is its ability to produce flow temperatures up to 70°C, which is ideal for homes with large older radiators that would typically need water at higher temperatures to heat a room effectively. It is available in 14 kW to 18 kW outputs, making it one of the more powerful models in the domestic market. Daikin’s intuitive app also offers user-friendly remote control and scheduling.
Performance and Reliability
Daikin is a globally established brand with a strong track record in heat pump technology. The ability to operate at -28°C provides a considerable performance buffer well beyond anything a Kent winter is likely to throw at it. This model is specifically designed for homes upgrading from a conventional gas or oil boiler without needing to replace radiators.
Costs
Fully installed costs range from approximately £12,000 to £20,000 before the BUS grant. The higher price reflects the unit’s power output and suitability for larger and older properties. After the £7,500 grant is applied, expect to pay between £4,500 and £12,500.
Best Suited For
Period properties, Victorian terraces, large detached homes with existing radiator systems, and properties in rural Kent where oil heating has historically been used.
Ratings
The Daikin Altherma 3 is independently reviewed as one of the best heat pumps for cold climates by the Federation of Master Builders (FMB).
| Pros | Cons |
| Operates reliably down to an exceptional -28°C, far beyond anything Kent winters produce | Highest price bracket in this guide, with installed costs reaching up to £20,000 before grant |
| High flow temperatures up to 70°C make it one of the best options for homes with older, larger radiators | Standard sound mode produces 38 dB(A) at 3 metres, noticeably louder at close range than the quietest models on this list, though a low sound mode reduces this to 35 dB(A) |
| A+++ seasonal efficiency rating with COP performance up to 5.43 | Higher output range makes it unsuitable for smaller properties that do not need 14 kW or more |
| Powerful output range of 14 kW to 18 kW suits larger and older properties | |
| Independently recognised as a top cold-climate performer by the FMB and EcoWatch | |
| No need to replace existing radiators in most retrofit situations |
Read our in-depth review of Daikin heat pumps.
4. Mitsubishi Ecodan – Best Budget-Friendly Air Source Heat Pump
The Mitsubishi Ecodan is one of the best budget-friendly air source heat pumps available in the UK, offering a long lifespan, reliable performance, and a wide range of output sizes to suit most residential properties.
| Category | Summary |
| Efficiency | A+++ rated, strong real-world efficiency across a broad temperature range |
| Performance and Reliability | Widely installed UK-wide, 20-year expected lifespan, large parts and installer network |
| Noise Levels | Ultra Quiet variant as low as 45 dB(A) at 1m; Quiet Mark certified since 2012 (sourced externally) |
| Costs | £8,000 to £14,000 installed before grant; £500 to £6,500 after grant |
| Best Suited For | Small to medium homes, buy-to-let landlords, new builds |
| Ratings | 4.3-star “Excellent” on Trustpilot |
Efficiency
The Ecodan carries an A+++ energy efficiency rating and is designed to work efficiently alongside underfloor heating and low-temperature radiator systems. It is known for solid real-world efficiency across a broad temperature range.
Key Features
Available in outputs from 5 kW to 14 kW, the Ecodan suits everything from small two-bedroom properties to larger family homes. One consideration to be aware of is that the hot water cylinder is sold separately, so this needs to be factored into your overall budget. The system is designed for low maintenance and can last around 20 years with proper care, making it a sound long-term investment.
Performance and Reliability
Mitsubishi Electric has a long-standing reputation for robust, reliable products. The Ecodan is one of the most widely installed heat pumps across the UK, which means there is a large pool of experienced installers and readily available parts. It is not the most powerful option on the market, but for the vast majority of Kent homes, its performance is more than adequate.
Costs
The Ecodan is among the more affordable options, with fully installed costs typically ranging from £8,000 to £14,000 before grant, making it one of the most accessible entry points into heat pump ownership after applying the £7,500 BUS grant. After the grant, the net cost typically falls between £500 and £6,500.
Best Suited For
Smaller to medium-sized homes, buy-to-let landlords looking for a cost-effective and low-maintenance solution, and new-build properties. It is a practical, no-fuss choice for landlords across Kent looking to improve the energy performance certificate (EPC) rating of a rental property.
Ratings
As of late 2025, Mitsubishi Electric UK holds a 4.3-star “Excellent” rating on Trustpilot, reflecting a strong track record of customer satisfaction.
| Pros | Cons |
| One of the most affordable fully installed options, from £8,000 before grant | Hot water cylinder is sold separately, adding to the overall project cost |
| A+++ energy efficiency rating with solid real-world performance | Not the most powerful unit on the market, so may not suit very large or poorly insulated properties |
| Long expected lifespan of around 20 years with proper maintenance | Standard (non-Ultra Quiet) models are less competitive on noise than the specific low-noise variants |
| Widely installed across the UK, meaning strong parts availability and a large pool of experienced installers | |
| Quiet Mark certified since 2012, with the Ultra Quiet variant reaching just 45 dB(A) sound pressure at one metre, among the quietest figures of any brand in this guide (sourced externally) | |
| Strong 4.3-star Trustpilot rating reflecting consistent customer satisfaction |
Read our in-depth review of Mitsubishi heat pumps.
5. Samsung EHS Mono HT Quiet – Quietest Air Source Heat Pump
The Samsung EHS Mono HT Quiet is the best air source heat pump for noise-sensitive installations, operating at sound levels as low as 35 dB(A) and earning a prestigious Quiet Mark certification.
| Category | Summary |
| Efficiency | A+++ rated, reliable output down to -25°C |
| Performance and Reliability | Consumer electronics precision, double-layered sound insulation |
| Noise Levels | As low as 35 dB(A), Quiet Mark certified |
| Costs | £9,000 to £15,000 installed before grant; £1,500 to £7,500 after grant |
| Best Suited For | Urban and suburban terraced or semi-detached homes in built-up Kent towns |
| Ratings | Positively rated for innovation and build quality |
Efficiency
The EHS Mono HT Quiet holds an A+++ energy efficiency rating and is capable of delivering consistent heating performance even in temperatures as low as -25°C. Its enlarged heat exchanger improves heat transfer and helps maintain output during the coldest spells.
Key Features
One of its most impressive attributes is the ability to produce hot water up to 70°C, which means it works effectively with older radiator systems in homes that have historically relied on gas central heating. It is available in 5 kW, 8 kW, 12 kW, and 16 kW outputs, with a compact and lightweight design that allows for flexible mounting positions. Samsung offers a standard 2-year manufacturer guarantee, extendable to 7 years when installed by an approved Samsung installer.
Performance and Reliability
Samsung brings consumer electronics precision to its heat pump range, and the EHS Mono HT Quiet reflects that attention to detail. Its double-layered sound insulation system makes it an ideal choice for densely populated residential areas or properties where neighbours are in close proximity, which is relevant for many towns and villages across Kent.
Costs
Fully installed costs range from approximately £9,000 to £15,000 before the BUS grant. The 7-year extended warranty with an approved installer adds strong peace of mind value to the overall package. After the £7,500 grant, expect to pay between £1,500 and £7,500.
Best Suited For
Urban and suburban properties, terraced and semi-detached homes in built-up areas of Kent such as Canterbury, Maidstone, and Tunbridge Wells, and any homeowner where minimising operational noise is a priority.
Ratings
Samsung is rated positively across independent heat pump review platforms, particularly for innovation and build quality.
| Pros | Cons |
| Exceptionally quiet, with sound levels as low as 35 dB(A) and Quiet Mark certification | Standard manufacturer warranty is only 2 years unless extended through an approved installer |
| A+++ energy efficiency rating with reliable output down to -25°C | Mid-range pricing means it is not the cheapest option, despite not offering the highest efficiency figures on this list |
| Flow temperatures up to 70°C suit homes with existing radiators | Brand has a shorter dedicated heat pump track record in the UK compared to specialists like Vaillant or Mitsubishi |
| Available across four output sizes (5 kW, 8 kW, 12 kW, 16 kW) for flexible sizing | |
| Warranty extendable to 7 years when installed by an approved Samsung installer | |
| Double-layered sound insulation ideal for terraced streets and built-up parts of Kent |
Read our in-depth review of Samsung heat pumps.
6. Panasonic Aquarea – Best Smart Technology
The Panasonic Aquarea is the best air source heat pump for smart home integration, featuring advanced T-CAP technology and SCOP ratings up to 5.12, one of the highest in its class.
| Category | Summary |
| Efficiency | SCOP up to 5.12, real-world winter COP 4.0 to 4.5 |
| Performance and Reliability | T-CAP technology maintains output to -20°C, 15 to 20-year lifespan |
| Noise Levels | Around 48 dB |
| Costs | £9,000 to £15,000 installed before grant; £1,500 to £7,500 after grant |
| Best Suited For | Environmentally conscious homeowners, solar PV owners, new builds |
| Ratings | Strong independent reviews for efficiency and smart functionality |
Efficiency
With SCOP ratings reaching 5.12 at a 35°C flow temperature, the Aquarea produces over five units of heat for every unit of electricity consumed, earning a firm A+++ energy label. In real-world UK conditions, particularly in milder southern England climates like Kent, users can expect COPs of between 4.0 and 4.5 during winter. This level of efficiency can reduce carbon emissions by up to 80% compared to a gas boiler.
Key Features
The Aquarea range covers outputs from 3 kW to 16 kW, making it versatile enough for small apartments up to large detached homes. Its T-CAP technology maintains full heating capacity and efficiency even at -20°C, removing any concerns about cold-weather performance in Kent winters.
The Smart Cloud app allows remote monitoring and control, and the system integrates with solar PV panels, making it an ideal companion for homeowners already invested in renewable energy.
Performance and Reliability
Panasonic has built a strong reputation for durable, long-lasting products across its technology portfolio. The Aquarea range is designed for a lifespan of 15 to 20 years, and positive user feedback consistently highlights its ease of use and reliability. It operates at a quiet 48 dB, suitable for most residential settings.
Costs
Fully installed Aquarea systems typically cost between £9,000 and £15,000 before the BUS grant. After the £7,500 grant is applied, the net cost typically falls between £1,500 and £7,500.
Best Suited For
Environmentally conscious homeowners, those with solar panels looking to maximise renewable energy use, new build properties, and well-insulated Kent homes looking for the best combination of efficiency and smart technology.
Ratings
Panasonic receives strong independent reviews for efficiency and smart functionality, with a growing base of satisfied UK users.
| Pros | Cons |
| SCOP up to 5.12, one of the highest efficiency figures of any heat pump in this guide | Real-world UK winter COP of 4.0 to 4.5 is strong but noticeably below the peak lab-tested SCOP figure |
| T-CAP technology maintains full heating capacity down to -20°C | Sound level of 48 dB is respectable but not class-leading compared to Samsung or Daikin’s low sound mode |
| Can reduce carbon emissions by up to 80% compared to a gas boiler | Best performance is tied to having a well-insulated property, which may require additional investment first |
| Integrates well with solar PV systems, ideal for renewable-focused homeowners | |
| Long expected lifespan of 15 to 20 years | |
| Smart Cloud app for full remote monitoring and control |
Read our in-depth review of Panasonic heat pumps.
7. LG Therma V – Best Value for Money
The LG Therma V is the best air source heat pump for value, combining competitive pricing, impressive energy efficiency, and a generous 7-year warranty that makes it an attractive package for homeowners and landlords alike.
| Category | Summary |
| Efficiency | Up to 4x more efficient than fossil fuel boilers, up to 60% lower running costs |
| Performance and Reliability | Reliable to -20°C to -25°C, emergency heating function |
| Noise Levels | As low as 35 dB(A) at 5m on the 9 kW Monobloc S; up to 63 dB(A) sound power on larger units (sourced externally) |
| Costs | £8,000 to £14,000 installed before grant; £500 to £6,500 after grant |
| Best Suited For | Landlords, buy-to-let properties, 2 to 4-bed homes seeking value |
| Ratings | Positive coverage from GreenMatch and the FMB |
Efficiency
LG claims the Therma V is up to four times more energy efficient than traditional fossil fuel boilers, and for every 1 kWh of electricity the heat pump uses, it generates between 2 and 4 kWh of heat energy from the air. It can produce up to five times as much heat as it consumes in optimal conditions and may reduce annual energy costs by up to 60%.
Key Features
The LG Therma V range operates effectively at temperatures as low as -20°C to -25°C. It features an intelligent seasonal heat adjustment function, and the updated LG ThinQ app makes monitoring and controlling the system simple.
An emergency heating operation function keeps your home warm even if the unit develops a fault, which is a genuinely reassuring feature for homeowners and landlords managing rental properties.
Performance and Reliability
The 9 kW LG THERMA V R32 Monobloc S is widely considered the best fit for typical two to three-bedroom homes across the UK. The 16 kW model is priced at around £6,400 supply-only, making it one of the more competitively priced larger units on the market.
Costs
LG’s 5 kW and 7 kW supply-only units are typically available for under £4,500, with the 16 kW model at around £6,400. Fully installed costs typically fall between £8,000 and £14,000 before the BUS grant. After the £7,500 grant, most Kent homeowners can expect to pay between £500 and £6,500. Read our guide on air source heat pump costs to learn more.
Best Suited For
Landlords, buy-to-let properties, owner-occupied homes seeking maximum value, and two to four-bedroom properties across Kent looking for a reliable and cost-conscious heat pump solution.
Ratings
LG has a strong presence in the UK renewable heating market, with the Therma V range receiving positive coverage from independent sources including GreenMatch and the FMB.
| Pros | Cons |
| Strong value for money, with installed costs from £8,000 before grant | Larger 16 kW models are noticeably louder, with sound power levels rising towards 60 to 63 dB(A) depending on configuration (sourced externally) |
| Can reduce annual energy costs by up to 60% compared to a conventional boiler | Efficiency figures, while good, generally sit below premium options like Vaillant, Viessmann or Panasonic at peak performance |
| Reliable operation down to -20°C to -25°C | Some of the most competitive pricing applies mainly to smaller 5 kW and 7 kW units |
| Generous 7-year warranty as standard | |
| Emergency heating function keeps the home warm even if a fault develops, valuable for landlords | |
| Sound pressure as low as 35 dB(A) at 5 metres on the Monobloc S 9 kW model, among the quieter units in this guide (sourced externally) |
Read our in-depth review of LG heat pumps.
8. Aira Heat Pump – Best Warranty and Comfort Guarantee
The Aira Heat Pump is fast becoming one of the most talked-about options for homeowners across Kent, and it has earned that reputation with an industry-leading warranty and a promise that few other brands are willing to make: a genuinely warm home, guaranteed.
| Category | Summary |
| Efficiency | SCOP up to 4.7, R290 refrigerant, reliable to -25°C |
| Performance and Reliability | Full in-house design, install and monitoring; 15-year warranty and Comfort Guarantee |
| Noise Levels | Between 47 and 51 decibels |
| Costs | £14,229 to £18,500 installed before grant; £6,729 to £11,000 after grant |
| Best Suited For | Homeowners prioritising warranty and comfort guarantees, larger family homes |
| Ratings | Around 4.4 out of 5 “Excellent” on Trustpilot |
Efficiency
Every model in the Aira range carries a SCOP of up to 4.7 at 35°C, which means that for every unit of electricity the system uses, it produces roughly 4.7 units of heat.
It runs on R290 refrigerant, the same naturally occurring, low-impact refrigerant used in several premium heat pumps, and it keeps working reliably down to outdoor temperatures of minus 25°C, which is far colder than Kent typically experiences even in a hard winter.
Key Features
Aira heat pumps come in 6 kW, 8 kW and 12 kW outputs, covering everything from a small terraced home to a large detached property over 200 square metres. Sound levels sit between roughly 47 and 51 decibels depending on the model, which is quieter than typical background chatter in a living room.
The system is fully controlled through the Aira app, and the company designs, supplies, installs and monitors the whole system itself rather than working through third-party fitters.
Performance and Reliability
Aira is a relatively new name in the UK, having launched here in 2023 backed by significant Scandinavian investment, but it has moved quickly to build trust. It holds a “Great” to “Excellent” rating on Trustpilot from well over a thousand verified customer reviews.
What genuinely sets Aira apart is its 15-year warranty covering parts, labour and performance, roughly double what most competitors offer, alongside a 15-year Comfort Guarantee promising your home will stay between 18°C and 22°C, with Aira committing to fix the system at its own cost if that promise is not met.
Costs
Fully installed Aira systems typically range from around £14,229 for the 6 kW unit up to £18,500 for the 12 kW model, before the £7,500 Boiler Upgrade Scheme grant. After the grant is applied, homeowners in Kent can expect to pay from roughly £6,729 up to £11,000, depending on property size.
Best Suited For
Homeowners who want maximum peace of mind and are happy to pay a little more upfront for a longer warranty and a performance guarantee. It is a strong option for larger family homes across Kent, particularly in areas like Sevenoaks and Tunbridge Wells, where homeowners are often looking for a long-term, low-hassle heating solution.
Ratings
Aira holds an “Excellent” score on Trustpilot, generally around 4.4 out of 5, with the majority of reviewers highlighting the warranty and customer support experience.
| Pros | Cons |
| Industry-leading 15-year warranty covering parts, labour and performance | Among the most expensive options in this guide, with installed costs reaching up to £18,500 before grant |
| Unique 15-year Comfort Guarantee promising a home temperature between 18°C and 22°C | Relatively new to the UK market, having only launched in 2023 |
| Single company designs, supplies, installs and monitors the whole system, removing third-party handoffs | SCOP of up to 4.7 is solid but below the very highest performers such as Grant Aerona³ R32 or Panasonic Aquarea |
| Strong Trustpilot rating of around 4.4 out of 5 from over a thousand reviews | |
| Reliable performance down to -25°C | |
| Quiet operation between 47 and 51 decibels |
Read our in-depth review of Aira heat pumps.
9. Octopus Energy Cosy 6 & 9 – Best for Smart Tariff Integration
The Octopus Energy Cosy 6 and Cosy 9 are two sizes within the same heat pump range, designed and sold directly by one of the UK’s largest energy suppliers, and they stand out for one simple reason: nobody makes it easier to pair your heat pump with genuinely cheap electricity.
| Category | Summary |
| Efficiency | SCOP 3.4 (Cosy 6) to 3.6 (Cosy 9), R290 refrigerant |
| Performance and Reliability | Single-provider install via Octopus teams and MCS partners; pairs with Cosy Octopus tariff |
| Noise Levels | Between 56 and 58 decibels |
| Costs | £11,959 to £12,000 installed before grant; around £4,459 after grant |
| Best Suited For | Cost-conscious homeowners and landlords open to switching energy supplier |
| Ratings | Strong reputation for value for money and installation simplicity |
Efficiency
The Cosy 6 and Cosy 9 are designed around a 50°C flow temperature, achieving a published SCOP of 3.4 for the Cosy 6 and 3.6 for the Cosy 9 in that configuration, rising towards 3.9 for the larger Cosy 12 model in the same range.
Both models use R290 refrigerant. While these SCOP figures sit a little below some of the premium competitors on this list, Octopus designs every installation to comfortably clear the 2.8 SCOP threshold required for Boiler Upgrade Scheme eligibility, with real-world performance typically landing well above that minimum.
Key Features
The Cosy 6 delivers a heating capacity of around 5.2 to 5.6 kW, while the Cosy 9 delivers roughly 8.1 to 8.7 kW, depending on flow temperature and outdoor conditions, making the pair suitable for anything from a small terraced home to a mid-sized four-bedroom house.
Both units can reach flow temperatures of up to 70°C, meaning they can often work with existing radiators rather than requiring a full underfloor heating system. Sound power sits between roughly 56 and 58 decibels. Every Cosy installation comes with an 8-year product warranty as standard.
Performance and Reliability
Octopus Energy designs, supplies and installs the Cosy range using its own in-house teams and MCS-certified partner installers, which gives homeowners a single point of contact for the whole project. The real advantage of the Cosy heat pump is not the hardware alone, it is the integration with the Cosy Octopus electricity tariff, which offers three daily windows of cheaper electricity specifically timed for heat pump use.
You do not need to be an existing Octopus Energy customer to have a Cosy heat pump installed, but you do need to switch to Octopus as your electricity supplier to unlock the Cosy Octopus tariff.
Costs
Octopus states that its typical installed price nationally, after the Boiler Upgrade Scheme grant, is around £4,459, among the most competitive figures in this guide. Before the grant, fully installed costs for the Cosy 6 or Cosy 9 typically fall between £11,959 and £12,000, though this varies with property size and the complexity of the installation.
Best Suited For
Cost-conscious homeowners and landlords across Kent who want a straightforward, all-in-one installation experience and are open to switching energy supplier to access lower running costs. It is a particularly good fit for smaller and medium-sized homes in towns like Ashford, Faversham and Dartford, where budget and simplicity are often the deciding factors.
Ratings
Octopus Energy has built a strong reputation for customer service across its broader energy business, and independent reviewers frequently highlight the Cosy range’s value for money and ease of installation as key strengths.
| Pros | Cons |
| Among the most competitively priced options after the grant, with a typical net cost of around £4,459 | SCOP figures of 3.4 to 3.9 are the lowest of any heat pump in this guide, though still comfortably above the BUS eligibility threshold |
| Single point of contact from design through to installation via Octopus Energy’s own teams | Full tariff savings require switching electricity supplier to Octopus Energy |
| Pairs with the Cosy Octopus tariff for genuinely cheaper electricity during set daily windows | Sound power of 56 to 58 decibels is on the higher end compared to the quietest models on this list |
| 8-year product warranty as standard | |
| Flow temperatures up to 70°C allow compatibility with existing radiators | |
| No need to be an existing Octopus Energy customer to have the system installed |
Read our in-depth review of the Octopus Cosy 6 heat pump.
10. Grant Aerona³ R32 – Best for Larger UK Homes and Cold-Climate Reliability
The Grant Aerona³ R32 has quietly become one of the most respected air source heat pumps among UK installers, thanks to genuinely impressive efficiency figures and an output range that stretches comfortably into larger, more demanding properties.
| Category | Summary |
| Efficiency | SCOP up to 5.4, A+++ rated, R32 refrigerant |
| Performance and Reliability | 40+ years of manufacturing heritage, monobloc design, reliable -20°C to +43°C |
| Noise Levels | Around 53 decibels at 1 metre, Quiet Mark approved |
| Costs | £9,000 to £16,000 installed before grant; £1,500 to £8,500 after grant |
| Best Suited For | Larger family and period homes across Kent, high-output needs |
| Ratings | Well regarded among UK installers for efficiency and build quality |
Efficiency
The Aerona³ R32 range delivers some of the highest SCOP figures of any heat pump in this guide, reaching up to 5.4 at a 35°C flow temperature on the larger models, with even the smaller 6 kW unit achieving a SCOP of around 4.6.
It carries an A+++ energy rating and uses R32 refrigerant, a widely trusted option that offers a meaningful environmental improvement over older refrigerant types while remaining compatible with a huge range of UK heating system designs.
Key Features
The range spans from 6 kW right up to 17 kW, giving it one of the broadest output windows of any heat pump on this list, and making it a genuine option for large detached family homes as well as smaller properties. It operates reliably down to minus 20°C and continues functioning up to plus 43°C, giving it comfortable headroom for anything Kent’s climate might produce.
Grant is a long-established Irish heating manufacturer with decades of experience in UK oil boiler and renewable heating markets, and the Aerona³ carries Quiet Mark approval alongside MCS certification.
Performance and Reliability
Grant has built its reputation over more than 40 years supplying heating equipment into the UK and Ireland, and the Aerona³ R32 benefits from that manufacturing pedigree. It is a monobloc design, meaning all the working parts are housed in the single outdoor unit, which tends to simplify installation and ongoing servicing. Sound pressure levels sit at around 53 decibels at one metre, comparable to a quiet office environment.
Costs
Fully installed costs for the Aerona³ R32 range typically fall between £9,000 for the smaller 6 kW unit and £16,000 for the larger 17 kW model, before the £7,500 Boiler Upgrade Scheme grant is applied. This makes it a genuinely competitive option for the amount of heating capacity it delivers. After the grant, expect to pay between £1,500 and £8,500.
Best Suited For
Larger family homes across Kent, particularly detached and period properties in areas such as Cranbrook, Tenterden and rural parts of the Weald where a higher-output system is often needed. Its strong cold-weather performance and wide output range also make it a sensible choice for anyone wanting one system capable of scaling as their heating needs change.
Ratings
Grant is consistently well regarded among UK heating installers for build quality and after-sales support, and the Aerona³ R32 is frequently cited in independent buying guides as one of the strongest performers on efficiency figures alone.
| Pros | Cons |
| SCOP up to 5.4, the highest efficiency figure of any heat pump featured in this guide | Larger 17 kW models push installed costs up to £16,000 before grant |
| Widest output range on this list, from 6 kW to 17 kW, suiting almost any property size | Less widely recognised by UK homeowners compared to household names like Mitsubishi or Vaillant, despite strong installer reputation |
| Reliable operation down to -20°C with a high upper limit of +43°C | As with any high-output system, oversizing for a smaller property would reduce overall efficiency |
| Over 40 years of manufacturing experience in the UK and Ireland | |
| Quiet Mark approved with sound pressure of around 53 decibels at one metre | |
| Monobloc design simplifies installation and servicing |
11. MasterTherm UK BoxAir Inverter – Best for Flexible Multi-Zone Heating
The MasterTherm BoxAir Inverter is less of a household name than some of the other brands in this guide, but for homes with more complex heating needs, such as multiple heating zones or larger properties with varied room usage, it is a genuinely capable and often overlooked option.
| Category | Summary |
| Efficiency | SCOP up to 4.92, A+++ rated, newer models use R290 |
| Performance and Reliability | Manufacturing since 1989, up to 6 heating zones from one system, 7-year warranty |
| Noise Levels | As low as 41 decibels at 5 metres on select models |
| Costs | £10,000 to £17,000+ installed before grant; £2,500 to £9,500+ after grant |
| Best Suited For | Larger homes, period properties with extensions or annexes, multi-zone heating needs |
| Ratings | Well regarded within the UK renewable heating installer community |
Efficiency
The BoxAir Inverter range achieves SCOP ratings of up to 4.92 at a 35°C flow temperature on its A+++ rated models, with the larger commercial-grade units in the range reaching similarly strong figures even at outputs approaching 30 kW.
Newer models in the range use R290 refrigerant, reflecting the same shift towards lower-impact refrigerants seen across the rest of the market, while offering flow temperatures up to 75°C.
Key Features
What makes the BoxAir Inverter stand out is its sheer flexibility, with outputs spanning from as little as 2 kW right up to 30 kW across the full range, and the ability to control up to six separate heating circuits from a single system. This makes it particularly well suited to larger homes with distinct zones, such as a converted barn, an annexe, or a period property with several separate living areas.
Sound levels are impressively low, with some models operating at around 41 decibels at 5 metres, among the quieter units covered in this guide. The system includes a built-in immersion heater and circulation pump as standard, simplifying installation in many cases.
Performance and Reliability
MasterTherm has been manufacturing heat pumps since 1989, giving it one of the longer track records of any brand in this guide, and its UK operation has been supplying and supporting installations for well over a decade.
All MasterTherm heat pumps come with a 7-year warranty as standard, which is comfortably ahead of the industry baseline of 2 to 5 years offered by several competitors. Its multi-zone control capability is particularly valued by installers working on larger or more architecturally complex properties.
Costs
Fully installed BoxAir Inverter systems typically range from around £10,000 for smaller domestic outputs up to £17,000 or more for the larger, higher-output models, before the £7,500 Boiler Upgrade Scheme grant is applied. After the grant, expect to pay between £2,500 and £9,500 or more, depending on the size and complexity of the system.
Best Suited For
Larger homes, period properties with multiple wings or extensions, and any property in Kent that needs several independently controlled heating zones rather than a single uniform system. It is also worth considering for rural properties across areas like the Kent Downs, where oil heating has historically been common and a flexible, high-capacity replacement is often needed.
Ratings
MasterTherm is well regarded within the UK renewable heating installer community for build quality and multi-zone flexibility, with over three decades of manufacturing experience underpinning its UK product range.
| Pros | Cons |
| Exceptional flexibility, with outputs spanning from 2 kW to 30 kW across the full range | Less well known among UK homeowners compared to mainstream brands, which may mean fewer local installers |
| Can control up to six separate heating circuits from a single system, ideal for zoned or extended properties | Multi-zone capability is most valuable for larger or more complex properties, so smaller homes may not benefit from its full feature set |
| Among the quietest units in this guide, with some models operating at just 41 decibels at 5 metres | Costs for larger, higher-output models can reach £17,000 or more before grant |
| Manufacturing heritage dating back to 1989, one of the longest track records in this guide | |
| 7-year warranty as standard, ahead of the 2 to 5 year industry baseline | |
| Built-in immersion heater and circulation pump simplify installation |
How We Chose the Best Air Source Heat Pumps
We chose the best air source heat pumps based on a structured, multi-criteria evaluation process developed through years of hands-on installation experience and continuous learning in the renewable heating industry.
At Guscott Heating, our team works with air source heat pump systems every day across properties throughout Kent and the wider South East, which means our recommendations are grounded in real installation knowledge, not just manufacturer specifications.
Here is exactly how we assessed each model:
Energy Efficiency and SCOP Ratings
We assessed each unit’s Seasonal Coefficient of Performance (SCOP), which reflects how efficiently a heat pump performs across a full heating season in UK conditions, not just in ideal lab testing. A higher SCOP means lower running costs for the homeowner. We prioritised models with A+++ energy ratings and real-world SCOP values above 4.0.
Suitability for UK Properties
Kent has a varied housing stock, from Victorian terraced homes and period farmhouses to modern new builds and semi-detached family homes. We evaluated each heat pump’s flow temperature capability, output range, and compatibility with both underfloor heating and standard radiator systems to ensure our recommendations work for a broad range of real property types.
Reliability and Build Quality
We considered each brand’s track record in the UK market, warranty terms, availability of local UK heat pump service engineers, and user feedback through platforms such as Trustpilot and Which? Long-term reliability matters far more than short-term savings, and we only recommend brands we trust to perform year after year.
Running Costs and Installation Costs
We factored in both the upfront cost of supply and installation, and the longer-term running costs based on efficiency ratings and typical Kent energy usage profiles. We also assessed which models qualify for the government’s Boiler Upgrade Scheme grant of £7,500, as this significantly affects the true cost to the homeowner.
Environmental Credentials
As a renewable energy installation company, environmental performance matters to us. We gave preference to models using lower-GWP refrigerants such as R290 and R32, and those delivering measurable reductions in carbon emissions for the properties they serve.
Noise Levels
For many homeowners and landlords in suburban and urban parts of Kent, the operational noise of an external heat pump unit is a real concern. We reviewed decibel ratings and real-world noise feedback for each model to ensure our recommendations are practical for typical residential settings.
Our team at Guscott Heating is MCS-certified, which is the quality mark required for heat pump installations to be eligible for the Boiler Upgrade Scheme grant. This means every installation we carry out meets the national standard for quality and safety, and your grant application is in safe hands.
How to Choose the Best Air Source Heat Pump for Your Property?
Choosing the best air source heat pump for your property comes down to matching the right model to your home’s size, insulation levels, existing heating system, and budget. Below is a practical buying guide to help you work through the key decisions.
Understand Your Home’s Heat Demand
Every property has a heat loss calculation that determines how many kilowatts of heating capacity it needs. A rough rule of thumb is that a well-insulated two-bedroom home may need a 5 kW to 7 kW system, while a larger four to five-bedroom home could require a 10 kW to 14 kW unit. A professional heat loss survey from a qualified installer like Guscott Heating will give you a precise figure based on your specific property.
Check Your Insulation First
Air source heat pumps work most efficiently in well-insulated homes. If your home has poor insulation, the heat pump will have to work harder, reducing its efficiency and increasing your running costs. Before installing a heat pump, it is worth addressing loft insulation, cavity wall insulation, and double glazing if any are lacking.
Your EPC report will highlight any outstanding insulation recommendations, which must be resolved before you can access the Boiler Upgrade Scheme grant anyway.
Read our in-depth guide on knowing if your home is suitable for a heat pump.
Radiators or Underfloor Heating
Most modern heat pumps work best when delivering water at lower temperatures, typically between 35°C and 55°C, which is ideal for underfloor heating. However, high-temperature models like the Daikin Altherma 3H HT and the Samsung EHS Mono HT Quiet can deliver water up to 70°C, making them compatible with standard radiators.
If your home has older, smaller radiators, you may need to either upgrade to larger radiators or opt for a high-temperature heat pump.
Consider the Noise Factor
Heat pumps have an outdoor unit that makes some noise during operation. Most modern units operate between 40 and 60 dB, roughly comparable to a quiet conversation or ambient background noise.
If your property is in a terraced street or close to your neighbour’s windows or outdoor space, choosing a quieter model such as the Samsung EHS Mono HT Quiet or the Vaillant aroTHERM Plus in silent mode is worth the consideration.
Factor in the Boiler Upgrade Scheme
The UK government’s Boiler Upgrade Scheme currently offers a grant of £7,500 for eligible air source heat pump installations. This grant is applied directly by your installer, so you never see the money yourself.
To qualify, the property must have a valid EPC with no outstanding insulation recommendations, and the installation must be carried out by an MCS-certified installer. Guscott Heating is MCS-certified, meaning every customer we serve in Kent can access this grant.
Think About Refrigerant Type
Newer heat pumps increasingly use R290 (propane) refrigerant, which has an extremely low Global Warming Potential compared to older refrigerants. R32 is also widely used and represents a significant improvement over older R410A. For homeowners in Kent who want to maximise the green credentials of their heating system, choosing a model using R290 or R32 is the right call.
Should You Choose a Manufacturer Warranty or an Installer-Backed Guarantee?
Warranty lengths vary considerably across the market, and it is worth understanding the difference before you commit. Standard manufacturer warranties on most heat pumps range from around 2 to 7 years, while some newer brands such as Aira now offer up to 15 years of combined parts, labour and performance cover.
A longer warranty generally means greater peace of mind and lower long-term risk, though it is not the only factor worth weighing. Always ask your installer to confirm exactly what is covered, for how long, and whether ongoing servicing is required to keep the warranty valid.
Should You Switch Energy Supplier for a Better Heat Pump Tariff?
Some heat pump brands, including the Octopus Energy Cosy range, are tied to specific smart electricity tariffs that offer cheaper rates during set windows of the day, designed to align with when a heat pump runs most efficiently. You do not need to switch supplier to have most heat pumps installed, but doing so can meaningfully reduce your running costs if the tariff suits your household’s habits.
It is worth comparing your current electricity tariff against any heat pump specific tariffs on offer before making your final decision, as the running cost difference over several years can be significant.
Landlords: The Opportunity in Kent
If you are a landlord in Kent, air source heat pumps represent a genuine opportunity to improve your property’s EPC rating, reduce tenant energy bills, and future-proof against tightening Minimum Energy Efficiency Standards (MEES) regulations.
The Boiler Upgrade Scheme is open to landlords who own the property, and the long-term reduction in maintenance compared to gas boilers makes heat pumps a particularly attractive proposition for rental properties.
Get a Professional Heat Loss Survey
The single most important step before choosing an air source heat pump is to get a professional heat loss survey carried out by a qualified installer. This ensures the unit is correctly sized for your property. An oversized or undersized heat pump will be less efficient, cost more to run, and may lead to comfort issues.
Get A Free Air Source Heat Pump Quote From Guscott Heating
Guscott Heating specialises in expert air source heat pump installations for homeowners and landlords across Kent. From Maidstone to Margate, Canterbury to Cranbrook, our team is on hand to guide you through every step. Get your free ashp quote today.
Frequently Asked Questions
Can an air source heat pump heat my home in winter?
Yes, modern air source heat pumps are designed to operate effectively in temperatures as low as -20°C to -28°C depending on the model, well below the typical temperatures experienced in Kent during winter.
Advanced inverter technology allows the heat pump to ramp up its output as outdoor temperatures drop, maintaining consistent indoor comfort throughout the colder months.
How long does an air source heat pump last?
With proper annual servicing and maintenance, most air source heat pumps have a lifespan of between 15 and 20 years. This is comparable to or longer than a typical gas boiler, and because heat pumps have fewer moving parts, they tend to require less frequent repairs over their lifetime.
Do I need planning permission to install an air source heat pump in Kent?
In most cases, air source heat pump installations in England fall under permitted development rights, which means planning permission is not required. However, there are exceptions for listed buildings, properties in conservation areas, and certain flats or apartments. Guscott Heating can advise you on your specific property and circumstances as part of the free quote process.
Will an air source heat pump work with my existing hot water cylinder?
Some heat pumps, such as the Vaillant aroTHERM Plus, are designed to work with compatible cylinder packages, while others like the Mitsubishi Ecodan require a separate cylinder purchase. In many retrofit installations, your existing cylinder may need to be replaced with a larger unvented cylinder to work effectively with the heat pump. Your installer will assess this as part of the system design.
How much could I save on my energy bills with an air source heat pump?
Actual savings depend on the efficiency of the heat pump, your property’s insulation, and the current energy tariffs in your area. As a general guide, LG states that its Therma V range can reduce annual energy costs by up to 60% compared to a conventional boiler.
With running costs starting from approximately £950 per year for a well-insulated home and with the £7,500 BUS grant reducing the upfront cost, an air source heat pump can pay for itself over time while delivering a genuinely warmer, more comfortable home.
Is the Octopus Energy Cosy heat pump only available to Octopus Energy customers?
No, you do not need to be an existing Octopus Energy customer to have a Cosy 6 or Cosy 9 heat pump installed, and anyone can request a quote regardless of their current energy supplier. However, to access the Cosy Octopus electricity tariff, which offers cheaper rates during set windows of the day and is specifically designed to work alongside a heat pump, you will need to switch your electricity supply to Octopus Energy.
What warranty comes with an air source heat pump, and does it vary between brands?
Warranty lengths vary significantly across the market. Most established brands offer somewhere between 2 and 7 years of standard cover, while MasterTherm offers a 7-year warranty as standard across its range. Newer entrants such as Aira have gone considerably further, offering a 15-year warranty on parts, labour and performance, alongside a separate 15-year Comfort Guarantee.
It is always worth checking exactly what is included before choosing a model, as cover can vary between parts only, parts and labour, or a fuller performance guarantee.
Can one heat pump system heat different zones of my house separately?
Yes, some heat pump models are specifically designed to manage multiple heating zones from a single outdoor unit. The MasterTherm BoxAir Inverter, for example, can control up to six separate heating circuits, making it a strong option for larger properties, homes with extensions or annexes, or period properties across Kent with distinct living areas that require independent temperature control.
Is a higher SCOP always the better choice when comparing heat pumps?
Not necessarily. SCOP is a useful measure of how efficiently a heat pump performs across a full UK heating season, but it should be considered alongside your property’s insulation, radiator or underfloor heating setup, noise requirements, warranty length and budget. A heat pump with a slightly lower SCOP but a longer warranty, quieter operation, or better suitability for your existing radiators may well be the more sensible choice for your specific home.
