Grant aerona heat pump review 2026: Pricing, Pros & Cons
Grant aerona heat pump review 2026: Pricing, Pros & Cons
Grant is a name many rural homeowners already trust, thanks to decades of oil boilers keeping farmhouses and village cottages warm. Today the company’s Aerona air source heat pumps are one of the most popular ways to replace those boilers. In this Grant Aerona heat pump review, we explain in plain English what the Aerona range costs, how efficient it is, which homes it suits best and how it compares with brands like Vaillant, Mitsubishi, Daikin and Octopus.
We are EE Renewables Ltd, and air source heat pump installation is all we do. We fit heat pumps across Greater London, Brighton, Oxford, Southampton, Bristol, Cardiff and the wider South of England and South Wales. Grant is based in Wiltshire, right in the middle of the area we cover, so this review is grounded in what we see in local homes rather than brochure promises.
Grant aerona heat pump review: At a Glance
Grant Aerona heat pumps are a dependable, mid priced option from a British manufacturer, and they are especially strong for homes moving away from oil or LPG heating. The table below covers everything you need to know about the Grant Aerona range at a glance.
| What you need to know | Grant Aerona heat pump |
|---|---|
| Manufacturer | Grant UK, based in Devizes, Wiltshire, founded in 1979 |
| Current range | Aerona R290 (newest models) and Aerona3 R32 monobloc heat pumps |
| Sizes | Roughly 6kW to 17kW |
| Refrigerant | R290 (natural propane, very low climate impact) on the newest range; R32 on Aerona3 |
| Maximum flow temperature | Up to around 70°C on the R290 range; lower on Aerona3 |
| Efficiency (SCOP) | Around 4.0 to 4.7 at 35°C flow; ErP rating A+++ at low temperature |
| Typical real world efficiency | Around 300% to 400% (3 to 4 units of heat per unit of electricity) |
| Unit price (supply only) | Roughly £3,500 to £7,000 depending on size |
| Typical installed cost before grant | Around £9,500 to £15,000 |
| Typical cost after £7,500 Boiler Upgrade Scheme grant | Around £2,000 to £7,500 |
| Typical annual running cost | Around £800 to £1,100 for an average 3 bed home |
| Warranty | Up to 7 years when fitted and registered by an approved Grant installer |
| Trustpilot rating (Grant UK) | Around 4 out of 5, from a fairly small number of reviews |
| Which? rating | No full Which? brand score yet for Grant heat pumps |
| Noise | Roughly 55 to 65 dB(A) sound power; low noise mode available |
| Maintenance | One professional service a year recommended |
| Controls | Grant controller with weather compensation; smart thermostat compatible |
| Best for | Rural and off gas homes, 3 to 5 bed houses, bungalows, oil boiler replacements |
| Less ideal for | Small flats and homes wanting a fully app led package |
In simple terms, Grant sits in the same price bracket as Ideal and Baxi, below premium brands such as Viessmann and Stiebel Eltron, and above budget names like Midea and Hisense.
Are Grant Aerona heat pumps worth it?
Grant Aerona heat pumps are worth it for most homeowners and landlords, particularly those replacing oil, LPG or old electric heating in larger or rural homes. They offer reliable performance, a good choice of sizes and strong UK support at a fair price, without the premium cost of some European brands.
The Aerona range uses a monobloc design, which means the refrigerant stays sealed inside the outdoor unit. The newest Aerona R290 models use natural propane refrigerant and reach higher water temperatures, which helps homes that want to keep more of their existing radiators.
EE Renewables Ltd only provides air source heat pump installation, and we cover Southern England, Greater London, South West England and South Wales, including London, Brighton, Oxford, Southampton, Bristol and Cardiff. If you would like to know whether a Grant Aerona suits your home, get in touch today for a heat pump quote tailored to your location.
Pros & Cons of Grant aerona heat pumps
| Pros | Cons |
|---|---|
| British manufacturer based in Wiltshire with long UK experience | Smaller brand than Mitsubishi, Daikin or Samsung |
| Strong choice for replacing oil and LPG boilers | Smart app features are basic compared with Octopus Cosy 6 or Aira |
| Wide size range up to around 17kW suits larger homes | Larger models are bulky outdoors |
| R290 models reach around 70°C, helping keep existing radiators | Higher flow temperatures reduce efficiency and raise bills |
| Up to 7 year warranty through approved installers | Full warranty depends on registration and yearly servicing |
| Grant also makes matching cylinders and underfloor systems | Fewer Trustpilot reviews to judge by |
| Competitive mid range pricing | Peak efficiency slightly behind Vaillant aroTHERM plus |
Is a Grant Aerona Heat Pump Right For Your Property?
Choose Grant Aerona if…
- You are replacing an oil, LPG or old storage heater system, common in rural Wiltshire, Dorset, Somerset, Devon and the Cotswolds.
- You live in a 3 to 5 bed house or bungalow that needs a medium or large heat pump.
- You want to keep as many existing radiators as possible.
- You prefer a British brand with technical support and parts based in the UK.
- You are a landlord looking for a dependable system to improve your property’s EPC.
- You want a matching cylinder and controls from the same manufacturer.
Do Not Choose Grant Aerona If…
- You live in a small flat with little outdoor space, where a compact unit from Samsung or LG might fit better.
- You want a fully bundled package with tariff, app and installation together, like Octopus or Aira offer.
- You want the very highest efficiency figures and are happy to pay more for brands like Vaillant or Viessmann.
- You are not willing to book a yearly service, as this can affect your warranty.
How efficient are Grant Aerona heat pumps?
Grant Aerona heat pumps are highly efficient, with seasonal efficiency (SCOP) figures of around 4.0 to 4.7 at a 35°C flow temperature. That means a Grant Aerona can produce roughly 4 units of heat for every 1 unit of electricity it uses. An oil boiler, by comparison, converts at best around 90% of its fuel into heat, and older oil boilers can be well below that.
SCOP and SPF explained simply
SCOP, or seasonal coefficient of performance, is the average efficiency measured in testing over a full heating season. SPF, or seasonal performance factor, is what the heat pump actually achieves once it is fitted in your home. Your MCS installer estimates your SPF during the design stage, and this is the number that really shapes your bills.
How flow temperature changes efficiency
The warmer the water a heat pump sends to your radiators, the harder it has to work. Here is a rough guide for the Grant Aerona R290:
| Flow temperature | Typical efficiency (approx.) | What it means for you |
|---|---|---|
| 35°C (underfloor heating, large radiators) | 400% to 470% | Lowest running costs |
| 45°C (some upgraded radiators) | 330% to 390% | A good balance for most homes |
| 55°C (mostly original radiators) | 280% to 320% | Higher bills, but still far cheaper than direct electric heating |
| 65°C to 70°C (very cold days or hot water boosts) | 200% to 250% | Best used only when needed |
Most of the Grant systems we see in Southern England are designed to run at around 45°C to 50°C, achieving real world efficiency of around 300% to 380%.
How Grant compares on efficiency
The Vaillant aroTHERM plus is often quoted with slightly higher SCOP figures, up to around 5.0. Grant’s R290 range is broadly level with the Mitsubishi Ecodan R290, Daikin Altherma 3 and Ideal Logic Air. The NIBE S2125 and Viessmann Vitocal 250 A are known for strong performance at higher flow temperatures, but they cost more. Gree and Haier units can post good lab figures, though real world results tend to vary more.
Does the Southern climate help efficiency?
Yes, the milder climate in Southern England and South Wales helps. Winter temperatures in places like Bristol, Exeter, Bournemouth and Cardiff often average around 5°C to 8°C, which is kinder to heat pumps than colder northern areas. A Grant Aerona fitted in the South will usually run more efficiently across the year than the same model further north.
How much does a Grant Aerona heat pump cost?
A Grant Aerona heat pump costs around £9,500 to £15,000 fully installed before grants, and around £2,000 to £7,500 after the £7,500 Boiler Upgrade Scheme (BUS) grant. The unit alone typically costs £3,500 to £7,000. The rest covers the hot water cylinder, pipework, radiator upgrades, controls, labour and MCS certification, and in oil homes, safely removing the old tank.
Grant Aerona pricing table
| Model (approx. output) | Typical home size | Unit price (supply only, approx.) | Installed cost before grant (approx.) | Installed cost after £7,500 BUS grant (approx.) |
|---|---|---|---|---|
| Aerona R290 6kW | Well insulated 2 to 3 bed home | £3,500 to £4,200 | £9,500 to £11,000 | £2,000 to £3,500 |
| Aerona R290 10kW | Average 3 to 4 bed house | £4,500 to £5,300 | £10,500 to £12,500 | £3,000 to £5,000 |
| Aerona R290 13kW | Larger 4 bed or older 3 bed home | £5,300 to £6,200 | £12,000 to £14,000 | £4,500 to £6,500 |
| Aerona R290 17kW | Large 4 to 5 bed or rural farmhouse | £6,000 to £7,000 | £13,000 to £15,000 | £5,500 to £7,500 |
What affects the final installation cost
- Radiator upgrades. Larger radiators typically add £300 to £600 each.
- Hot water cylinder. A new heat pump cylinder usually costs £1,200 to £2,500 fitted.
- Oil tank removal. Draining and removing an old oil tank can add £300 to £800.
- Pipework. Narrow or old pipes sometimes need upgrading.
- Location. Labour costs in London are usually higher than in places like Salisbury, Taunton or Swansea.
Grants and tax savings
The Boiler Upgrade Scheme gives homeowners and landlords in England and Wales £7,500 off an air source heat pump, paid directly to your MCS certified installer. Heat pump installations also currently benefit from 0% VAT in Great Britain until March 2027. For off gas homes, the savings over replacing an oil boiler like for like can be significant.
How Grant pricing compares with other brands
Grant is usually priced close to Ideal, Baxi and Worcester Bosch. Mitsubishi Ecodan and Daikin Altherma systems can be similar or a little higher, while Viessmann, NIBE and Stiebel Eltron often cost £1,000 to £3,000 more for the same size. Midea and Hisense can be cheaper to buy. Octopus Cosy 6 and Aira use bundle pricing that includes installation and controls, which makes direct comparison harder.
What are the running costs of a Grant Aerona heat pump?
The running costs of a Grant Aerona heat pump are typically around £800 to £1,100 a year for an average 3 bed home in Southern England on a standard electricity tariff. On a dedicated heat pump or time of use tariff, this can drop to around £550 to £750 a year.
A worked example for a typical 3 bed home
A typical 3 bed house uses about 12,000 kWh of heat a year for heating and hot water. Assuming electricity at around 26p per kWh (close to current Ofgem price cap levels, which change every quarter), here is what a Grant Aerona would cost to run:
| Real world efficiency (SPF) | Electricity used per year (approx.) | Yearly cost at 26p/kWh (approx.) | Yearly cost on a 17p/kWh heat pump tariff (approx.) |
|---|---|---|---|
| 3.0 (older radiators, higher flow temperature) | 4,000 kWh | £1,040 | £680 |
| 3.5 (typical well designed system) | 3,430 kWh | £890 | £580 |
| 4.0 (low flow temperature, good insulation) | 3,000 kWh | £780 | £510 |
How this compares with oil and LPG
The same home heated by an oil boiler would need roughly 1,300 to 1,400 litres of heating oil a year. At around 65p to 75p per litre, that is about £850 to £1,050, and oil prices can jump sharply, as they did in 2022. LPG is often more expensive still. A well designed Grant Aerona on a heat pump tariff can therefore cut heating bills by several hundred pounds a year for off gas homes, while also removing the cost of oil deliveries and tank maintenance.
Tips to lower your running costs
- Turn on weather compensation. It lowers the water temperature on milder days, which is most of the year in the South.
- Run it low and steady. Heat pumps work best keeping a constant temperature rather than switching on and off like a boiler.
- Choose a heat pump tariff. Suppliers like Octopus, OVO and EDF offer cheaper rates at certain times.
- Add solar panels. Rural homes often have the roof space to pair a Grant Aerona with solar PV.
Tech led systems such as the Octopus Cosy 6 and Aira lean heavily on their apps and tariffs to keep bills down. Grant relies on solid hardware and good installation, which in our experience delivers similar savings when the system is designed properly.
What warranty comes with a Grant Aerona heat pump?
The warranty that comes with a Grant Aerona heat pump is up to 7 years when the system is installed by a Grant approved installer and registered with Grant after commissioning. Standard cover is shorter if those conditions are not met, so always check the exact terms on your quote.
How to keep your Grant warranty valid
- Use an MCS certified installer who is approved or accredited by Grant.
- Register the heat pump with Grant within the time limit set in the warranty terms.
- Book a professional service every 12 months and keep the records.
- Use genuine Grant parts for any repairs.
How Grant’s warranty compares
| Brand | Typical maximum heat pump warranty (approx.) |
|---|---|
| Grant Aerona | Up to 7 years |
| Vaillant aroTHERM plus | Up to 10 years via approved installers |
| Mitsubishi Ecodan | Up to 7 years via accredited installers |
| Daikin Altherma | Up to 7 years via Stand By Me registration |
| Ideal Logic Air | Up to 7 years |
| Worcester Bosch | Up to 7 to 10 years depending on installer scheme |
| Aira | 15 year package cover including installation |
Grant’s warranty matches most big name brands, though Vaillant and Aira currently offer longer headline cover. Your MCS installer should also give you a separate workmanship warranty on top. At EE Renewables, both are clearly explained on every quote.
Which property types are Grant Aerona heat pumps best suited for?
Grant Aerona heat pumps are best suited for medium to large houses, bungalows and rural off gas properties, especially those replacing oil or LPG boilers. The range of sizes up to around 17kW means even bigger farmhouses and detached homes can usually be heated with a single unit.
| Property type | How well a Grant Aerona suits it | Things to consider |
|---|---|---|
| Rural off gas home (oil or LPG) | Excellent | Grant’s core strength; oil tank removal frees up garden space |
| 3 to 4 bed semi or detached house | Excellent | Usually the 10kW or 13kW model |
| Bungalow | Excellent | Plenty of room outside and simple pipe runs |
| Large 4 to 5 bed detached or farmhouse | Very good | The 13kW or 17kW model; insulation upgrades help |
| Rental property (landlords) | Very good | Helps lift EPC ratings ahead of proposed rental rules |
| Victorian or period terrace | Good | Solid walls lose more heat; check radiator sizes carefully |
| Modern new build | Good | A 6kW model often suits; very small homes may want a more compact unit |
| Flats and listed buildings | Limited | Space, planning and noise rules can make any outdoor unit tricky |
Why Grant is popular for oil boiler replacement
Around 1 in 7 homes in Great Britain are not connected to the gas grid, and many of them sit in rural parts of the South West, Wiltshire, Dorset, Hampshire and South Wales. Grant has been supplying oil boilers to these homes for decades, so its installers and engineers know these properties well. The step from a Grant oil boiler to a Grant Aerona feels natural to many owners, though Mitsubishi, Daikin, Vaillant and NIBE also make excellent oil replacement systems.
A note for landlords
The government has proposed that privately rented homes in England and Wales should reach EPC band C by 2030. Off gas rental homes heated by oil or electric storage heaters often have low EPC ratings, so a heat pump plus insulation is one of the most effective upgrades. Landlords can claim the £7,500 BUS grant too, as long as the property meets the scheme rules.
How noisy are Grant Aerona heat pumps?
Grant Aerona heat pumps are reasonably quiet, with sound power levels of roughly 55 to 65 dB(A) depending on the model and how hard the unit is working. A few metres away, most people compare the sound to a fridge or a gentle fan hum.
What the noise figures actually mean
The datasheet figure is sound power, which is the noise at the unit itself. What you and your neighbours hear is sound pressure, and that drops quickly with distance. Under the MCS planning standard, noise at the nearest neighbour’s window must stay at or below 42 dB(A) for permitted development. That is roughly the level of a quiet library.
Low noise mode and placement
The Aerona range includes a low noise or night mode that limits fan and compressor speed during set hours. Placement matters just as much. In rural homes there is often plenty of space to put the unit well away from bedrooms and neighbours. In tighter towns such as Brighton, Bath or Oxford, careful siting away from walls that bounce sound is important.
How Grant compares on noise
The Vaillant aroTHERM plus and Samsung EHS Mono R290 are often seen as among the quietest heat pumps available. Daikin Altherma 3 and Hitachi Yutaki units are also known for low noise. Grant’s larger models sit in the middle of the pack, similar to Panasonic Aquarea and LG Therma V units of a similar size, and generally quieter than older Dimplex and York designs.
What maintenance and servicing do Grant Aerona heat pumps need?
Grant Aerona heat pumps need one professional service a year, plus a few easy checks you can do yourself. Compared with an oil boiler, there is no fuel to order, no tank to inspect and no burner or flue to clean. An annual service typically costs around £120 to £200 in Southern England.
What a yearly service includes
- Inspecting the outdoor unit’s fan, coil and electrical connections
- Checking system pressure and topping up if needed
- Cleaning the strainer and magnetic filters
- Checking frost protection and antifreeze settings where used
- Reviewing flow temperatures, weather compensation and schedules
- Testing the hot water cylinder and its safety valves
- Recording the service to keep your warranty valid
Simple checks you can do at home
- Keep leaves, snow and garden plants at least 30cm clear of the outdoor unit.
- Check the pressure gauge every few months.
- Make sure nothing blocks airflow at the front of the unit.
- Look out for error codes on the controller.
How long does a Grant Aerona last?
A well maintained air source heat pump usually lasts 15 to 20 years, and sometimes longer, compared with around 10 to 15 years for many boilers. Grant’s UK based technical team and parts supply are a real plus, much like Worcester Bosch, Baxi and Ideal. Some lesser known imported brands, such as certain Gree or Haier models, can mean longer waits for spare parts.
What do Grant Aerona heat pump ratings and reviews say?
Grant Aerona heat pump ratings and reviews are generally positive, with Grant UK scoring around 4 out of 5 on Trustpilot at the time of writing, from a fairly small number of reviews. Which? has not published a full brand score for Grant heat pumps yet, so installer feedback and owner experiences matter more for now.
Trustpilot
Grant UK has far fewer Trustpilot reviews than big consumer facing brands, and many relate to oil boilers rather than heat pumps. The feedback that does mention the Aerona range tends to follow a few themes:
- Positive: helpful technical support, steady performance and good results when replacing oil heating.
- Negative: occasional waits for engineer visits and issues that come down to poor system design rather than the heat pump itself.
By comparison, Octopus Energy and Aira have large numbers of Trustpilot reviews because they sell directly to homeowners. Manufacturers such as Vaillant, Mitsubishi and Worcester Bosch usually score in a similar range to Grant.
Which?
Which? surveys heat pump owners and publishes satisfaction and reliability scores for brands with enough responses. Bigger brands like Mitsubishi, Vaillant, Daikin and Samsung have appeared in these results because of their large installed base. Grant has a smaller share of the market, so it has not yet gathered enough owner responses for a full score. Which? also points out that installation quality has a huge effect on how satisfied owners are, whatever the brand.
What these ratings mean for you
Ratings are a helpful starting point, but the biggest factor in your experience is how well the heat pump is designed and fitted. Pick an MCS certified installer with strong local reviews and ask to see examples of their past Grant installations.
What does installing a Grant Aerona heat pump involve?
Installing a Grant Aerona heat pump usually takes 2 to 5 days once the design is agreed, and most homes do not need planning permission. Everything starts with a home survey and room by room heat loss calculation, which tells your installer exactly which Aerona model your home needs.
The installation process step by step
- Home survey. An MCS certified installer checks each room, your insulation, windows, radiators and where the outdoor unit could go.
- System design and quote. You get a clear quote with the recommended model, cylinder, any radiator upgrades and the expected efficiency.
- BUS grant application. Your installer applies for the £7,500 Boiler Upgrade Scheme grant for you.
- Removing the old system. Your old boiler is taken out, and for oil homes the tank is drained and removed.
- Installation. The outdoor unit, cylinder, pipework and any new radiators are fitted.
- Commissioning and handover. The system is filled, tested and set up, then you receive your MCS certificate, warranty registration and a walk through of the controls.
Planning permission in Southern England and South Wales
In England, most air source heat pumps are permitted development. The old rule requiring units to sit at least 1 metre from a boundary was removed in 2025, which helps homes with small gardens in London, Bristol and Brighton. The unit must still meet MCS noise limits, and listed buildings, flats and some conservation areas may need permission. Wales has its own permitted development rules, so homes in Cardiff, Swansea and the Vale of Glamorgan should have this checked during the survey.
Why the installer matters as much as the brand
An undersized or poorly set up heat pump will disappoint, whether it is a Grant, Mitsubishi, NIBE or Panasonic. A careful heat loss survey, correct sizing and sensible flow temperatures are what keep your home warm and your bills low.
What controls and smart features do Grant Aerona heat pumps have?
Grant Aerona heat pumps come with a dedicated controller that offers weather compensation, heating and hot water schedules, and a low noise mode, and they can work alongside compatible smart thermostats. The controls are practical and reliable, though less app focused than some newer, tech led rivals.
Key control features
- Weather compensation. An outdoor sensor adjusts water temperature to the weather, one of the simplest ways to cut bills.
- Heating and hot water schedules. Useful for busy households and rental properties.
- Low noise mode. Reduces sound at night or set times.
- Smart thermostat compatibility. Pair with compatible room thermostats for remote control from your phone.
- Legionella protection. The cylinder is periodically heated to a higher temperature to keep stored water safe.
How Grant’s controls compare
The Octopus Cosy 6 and Aira are built around their apps, with live efficiency data and smart tariff integration. Mitsubishi’s MELCloud and Daikin’s Onecta apps are also more developed. Grant’s approach suits homeowners and landlords who want to set things up once and leave them alone. If you like detailed energy data, ask your installer about adding a heat meter or energy monitor.
Ready to get a free air source heat pump quote from EE Renewables?
Getting a free air source heat pump quote from EE Renewables is quick, easy and comes with no obligation. Our MCS certified team will survey your home, calculate exactly what size heat pump you need and show you the true cost, including the £7,500 Boiler Upgrade Scheme grant.
Request your free heat pump quote today and find out how much you could save with a heat pump tailored to your home and location.
EE Renewables Ltd only provides air source heat pump installation, so it is all we focus on. We help homeowners and landlords across Southern England, Greater London, South West England and South Wales, including London, Brighton, Oxford, Southampton, Bristol and Cardiff. Whether a Grant Aerona is the perfect match for your home or another brand would suit you better, we will give you honest, independent advice.
Frequently Asked Questions
What is the difference between the Grant Aerona3 and Aerona R290?
The difference between the Grant Aerona3 and Aerona R290 is mainly the refrigerant and the maximum water temperature. The Aerona3 uses R32 refrigerant, while the newer Aerona R290 uses natural propane, which has a much lower climate impact and allows higher flow temperatures of around 70°C. Most new installations now use the R290 models.
Do Grant Aerona heat pumps work in freezing weather?
Yes, Grant Aerona heat pumps work in freezing weather and are designed to keep heating homes in outdoor temperatures well below zero, down to around minus 20°C. The unit runs short defrost cycles to clear ice from the outdoor coil, which is completely normal. In Southern England, temperatures rarely fall below minus 5°C.
Is the R290 refrigerant in a Grant Aerona safe?
Yes, the R290 refrigerant in a Grant Aerona is safe when installed correctly. Only a small amount of propane is sealed inside the outdoor unit and none of it enters your home. Installers follow set clearance zones around the unit, so its position near doors, windows and drains is checked during the survey.
Can I keep my oil boiler as a backup with a Grant Aerona?
You can keep an oil boiler alongside a heat pump in a hybrid setup, but you would lose eligibility for the £7,500 Boiler Upgrade Scheme grant. The BUS grant requires the heat pump to fully replace your fossil fuel heating. A correctly sized Grant Aerona is designed to heat your home on its own, even on the coldest days.
Does a Grant Aerona heat pump add value to my home?
A Grant Aerona heat pump can add value to your home by improving its EPC rating and reducing running costs for future buyers. Research from property and energy groups suggests homes with better EPC ratings can sell for several percent more. Off gas homes moving away from oil often see the biggest EPC improvements.
