The main types of heat pumps used in UK homes are air source heat pumps, ground source heat pumps, water source heat pumps, hybrid heat pumps and exhaust air heat pumps.
Each one does the same basic job. It collects free, natural warmth from the air, the ground or water outside your home and moves it indoors to heat your rooms and your hot water. The difference lies in where that heat comes from, how much the system costs to install and how cheaply it runs once it is in.
Here at Guscott Heating, we install heat pumps for homeowners and landlords right across Kent and the South East, from Maidstone and Canterbury to Tunbridge Wells and Dartford. We get asked the same questions on almost every survey. Which heat pump is right for my house? What will it cost to run? Will it actually keep us warm in January? This guide answers all of that so you can choose with confidence.
Different Types of Heat Pumps: At a Glance
For most houses in Kent, an air to water air source heat pump is the most practical and affordable choice. It needs no digging, fits outside like a large air conditioning unit and connects to your existing radiators and hot water cylinder.
Here is a quick side by side view before we look at each type in more detail.
| Heat pump type | Where the heat comes from | Best suited to | Typical efficiency (SCOP) | Typical lifespan |
| Air to water (air source) | Outdoor air | Most houses, bungalows and larger flats | 3 to 4 | 15 to 20 years |
| Air to air (air source) | Outdoor air | Flats, conservatories, garden offices, single rooms | 3 to 5 | 12 to 15 years |
| Ground source | Soil or rock below ground | Rural and detached homes with land | 3.5 to 4.5 | 20 to 25 years (ground loop 50+ years) |
| Water source | Lake, river or pond | Homes next to a suitable body of water | 4 to 5 | 20 to 25 years |
| Hybrid | Outdoor air plus a gas or oil boiler | Homes not ready to switch fully | Varies | 15 to 20 years |
| Exhaust air | Warm air leaving the home | New build, very airtight homes | 2.5 to 3.5 | 15 to 20 years |
SCOP stands for seasonal coefficient of performance. In simple terms, a SCOP of 3 means you get around 3 units of heat for every 1 unit of electricity you pay for, averaged across a whole year. Figures are typical ranges and real results depend on your home, your system design and how you use it.
Not sure which type suits your home? Guscott Heating provides air source heat pump installation across Kent and the wider South East of England. Our team will visit, measure your home’s heat loss properly and recommend the right system for your property and budget. Get in touch today for a free estimate tailored to your location.
1. Air Source Heat Pump
An air source heat pump is a unit that sits outside your home and draws heat from the outdoor air to warm your property. It is by far the most popular renewable heating system in the UK. Air source models make up the large majority of heat pumps installed under the government’s Boiler Upgrade Scheme, largely because they are cheaper to fit than ground source systems and work on almost any type of house.
The outdoor unit looks a bit like a large air conditioning box. It needs a clear patch of wall or ground, usually at the side or back of the house, with space for air to flow freely around it. Well known manufacturers include Mitsubishi Electric (Ecodan), Daikin (Altherma), Vaillant (aroTHERM plus), Samsung and Grant. There are two main kinds of air source heat pump.
Air to Water Heat Pumps
Air to water heat pumps take heat from the outside air and pass it into water. That warm water then runs through your radiators or underfloor heating and heats your hot water cylinder, just as a boiler would.
This is the system most Kent homeowners mean when they talk about getting a heat pump, and it is the type we install most often in towns such as Maidstone, Tonbridge and Faversham.
The key benefits are:
- Whole home heating and hot water from one system.
- Eligible for the £7,500 Boiler Upgrade Scheme grant in England and Wales when fitted by an MCS certified installer.
- No digging or groundwork, so installation usually takes just two to five days.
- Works with your existing pipework, although some radiators may need upgrading.
You will usually need a hot water cylinder, because heat pumps work best heating water slowly and storing it. If you currently have a combi boiler, we will plan where a cylinder can go as part of your survey.
Pros and Cons of Air to Water Heat Pumps
| Pros | Cons |
| Heats your whole home and your hot water from one system | Usually needs a hot water cylinder, so you need some indoor space |
| Qualifies for the £7,500 Boiler Upgrade Scheme grant | Some radiators may need upgrading to run at their best |
| No digging, and most installs take just two to five days | Slightly less efficient than ground source on the coldest days |
| Running costs can match or beat gas on a smart tariff | Needs a clear outdoor spot with good airflow for the unit |
| Suits most Kent homes, from new builds to older semis | Costs more upfront than a straight boiler swap |
Air to Air Heat Pumps
Air to air heat pumps take warmth from outside and blow it straight into your rooms as warm air through wall mounted indoor units. They are the same technology as modern air conditioning, so they can also cool your home on hot summer days, which is handy in the South East where summers are getting warmer.
The drawbacks are that air to air systems do not heat your hot water, so you would need a separate way to do that, such as an electric immersion heater. They also suit open plan spaces, flats and single rooms better than whole houses with lots of small rooms. Historically they have not qualified for the Boiler Upgrade Scheme, so check the latest grant rules with your installer before you commit.
Pros and Cons of Air to Air Heat Pumps
| Pros | Cons |
| Lower upfront cost than an air to water system | Does not heat your hot water |
| Can cool your home in summer as well as heat it | Has not traditionally qualified for the Boiler Upgrade Scheme |
| Very efficient at warming individual rooms | Less suited to homes with lots of small, separate rooms |
| Quick to fit, often around a day per room | Indoor wall units are visible and some people dislike warm air heating |
Monobloc and Split Systems
Air to water heat pumps come in two designs. A monobloc system keeps all the working parts in the outdoor unit and simply sends warm water into the house. It is simpler to install and is the most common choice for UK homes. A split system divides the parts between an outdoor unit and an indoor unit, linked by refrigerant pipes. Splits can suit homes where the outdoor unit has to sit further from the house, or where space outside is tight.
Many newer monobloc models use a natural refrigerant called R290, which is propane. It has a far lower impact on the climate than older refrigerants and lets the heat pump reach higher water temperatures, which is useful in older Kent properties.
2. Ground Source Heat Pump
A ground source heat pump is a system that collects heat stored in the soil or rock beneath your garden through a loop of buried pipes. A meter or two below the surface, the ground in the UK stays at roughly 10°C to 12°C all year round. That steady temperature is why ground source systems are slightly more efficient than air source ones, especially on the coldest winter mornings.
A mix of water and antifreeze flows through the buried pipes, picks up that natural warmth and carries it back to a heat pump unit inside your home, usually in a utility room, garage or outbuilding. There are two ways to lay the pipes.
Horizontal Ground Loops
Horizontal loops are laid in long trenches around 1 to 2 metres deep. They are the cheaper option, but you need a good amount of open land. As a rough guide, a typical family home may need a garden area two to three times the size of the floor space being heated. This can work well for farmhouses and rural properties in the Kent Weald, around villages near Cranbrook (TN17) or Tenterden (TN30).
Vertical Boreholes
Vertical boreholes are drilled straight down, often between 60 and 200 metres deep. They take up very little garden space but cost a lot more because of the specialist drilling. Ground conditions matter too. Parts of Kent sit on chalk, clay or sand, and a geological check is needed before any drilling starts.
When Ground Source Makes Sense in Kent
Ground source is worth considering if you have plenty of land, a large or high heat demand home, or you plan to stay put for many years. The ground loop itself can last 50 years or more. For most suburban homes in places like Gillingham, Chatham or Gravesend, though, the higher upfront cost and disruption of digging mean an air source heat pump usually makes far better financial sense.
Both qualify for the same £7,500 Boiler Upgrade Scheme grant, so the grant covers a much smaller share of a ground source system.
Pros and Cons of Ground Source Heat Pumps
| Pros | Cons |
| The most efficient common type, thanks to steady ground temperatures | The highest upfront cost of any heat pump type |
| Long lifespan, with ground loops lasting 50 years or more | Needs a large garden for trenches or specialist borehole drilling |
| No outdoor fan unit, so it is almost silent outside | Groundwork is disruptive and your garden needs time to recover |
| Qualifies for the £7,500 Boiler Upgrade Scheme grant | A geological check is needed before work can begin |
3. Water Source Heat Pump
A water source heat pump is a system that draws heat from a nearby lake, river, pond or stream using pipes or panels placed in the water. Water holds heat well and stays at a fairly even temperature through winter, so these systems can be very efficient.
They are only an option if you have a large enough body of water on or right next to your land, and you will usually need permission from the Environment Agency. In practice they are rare for individual homes and more common for larger estates and community heat networks.
A handful of riverside properties along the Medway or the Stour may be suitable, but for nearly everyone else, air source or ground source is the realistic choice.
Pros and Cons of Water Source Heat Pumps
| Pros | Cons |
| Very high efficiency, as water holds heat well | Only possible with a suitable lake, river or pond close by |
| Water temperatures stay fairly steady through winter | Usually needs permission from the Environment Agency |
| Quiet, with very little equipment on show | Specialist design means few installers offer it |
| Low running costs once installed | Pipes or panels in the water need occasional checks for debris |
4. Hybrid Heat Pump
A hybrid heat pump is a heating setup that pairs an air source heat pump with a gas, LPG or oil boiler, with smart controls deciding which one to use at any moment. The heat pump does most of the work through spring, autumn and milder winter days, and the boiler steps in during very cold spells or when you need a lot of hot water quickly.
Hybrids can suit homes that are not quite ready for a full heat pump, such as larger, draughty older properties. However, there are two big catches. Hybrid systems do not qualify for the Boiler Upgrade Scheme grant, because they still burn fossil fuel. You also keep paying a gas standing charge and servicing two appliances. For most Kent homes, a properly sized standalone air source heat pump is the better long term investment.
Pros and Cons of Hybrid Heat Pumps
| Pros | Cons |
| Lower upfront cost than a full heat pump system | Not eligible for the Boiler Upgrade Scheme grant |
| The boiler backs up the heat pump on the coldest days | You still burn fossil fuel and pay a gas standing charge |
| A gentle first step for larger or draughtier homes | Two appliances to service and maintain |
| Can cut your gas use considerably | Smaller carbon and bill savings than a standalone heat pump |
5. Exhaust Air Heat Pump
An exhaust air heat pump is a system that recovers warmth from the stale air leaving your kitchen and bathrooms and reuses it to heat your home and water. It doubles as a whole house ventilation system, pulling fresh air in as the stale air is extracted.
These systems need a very airtight, well insulated home to work properly, so they are mostly found in modern new builds and flats. They are rarely a good fit for the older terraces and semis common across Medway, Thanet and East Kent.
Pros and Cons of Exhaust Air Heat Pumps
| Pros | Cons |
| Provides heating, hot water and ventilation in one unit | Only works well in very airtight, well insulated homes |
| No outdoor unit needed | Limited heat output, so unsuitable for larger homes |
| Well suited to small new build homes and flats | Generally less efficient than an air source heat pump |
| Helps keep indoor air fresh and reduces condensation | Filters need regular cleaning or changing |
6. High Temperature Heat Pump
A high temperature heat pump is an air source heat pump designed to heat water to around 70°C to 80°C, close to what a traditional boiler produces. Standard heat pumps run most efficiently at lower water temperatures, around 35°C to 50°C. High temperature models make it easier to switch homes with older radiators and less insulation, including many Victorian and Edwardian houses in Canterbury, Tunbridge Wells and Sevenoaks.
The trade off is that running at higher temperatures uses more electricity, so efficiency drops. A good installer will still design the system to run as cool as your home allows for most of the year, only turning up the temperature when it is genuinely cold.
Pros and Cons of High Temperature Heat Pumps
| Pros | Cons |
| Often works with your existing radiators | Costs more to run when working at higher temperatures |
| Fewer home upgrades needed before switching | Can cost more to buy than a standard model |
| Heats hot water quickly to boiler like temperatures | Still works best alongside good insulation |
| Qualifies for the £7,500 Boiler Upgrade Scheme grant | Efficiency relies heavily on careful system design |
How Do Running Costs Compare Between the Types of Heat Pumps?
Running costs between the types of heat pumps compare mainly on efficiency: the higher the SCOP, the less electricity you buy and the lower your bills. Ground source systems are usually the cheapest to run, standard air to water heat pumps come a close second, and high temperature models cost a little more.
All of them are far cheaper to run than direct electric heating, and on the right tariff a well installed air source heat pump can match or beat a gas boiler.
What Efficiency Means for Your Bills
Efficiency is the single biggest factor in your heat pump running costs. Think of SCOP as miles per gallon for your heating. A heat pump with a SCOP of 4 needs 25% less electricity than one with a SCOP of 3 to produce the same warmth. That is why careful system design, correctly sized radiators and sensible controls matter so much.
The government funded Electrification of Heat project, which monitored around 750 heat pumps in real UK homes, found that heat pumps can work well in every type of property it tested, from Victorian terraces to 1960s flats.
Example Annual Running Costs
The table below shows rough yearly costs for a typical three bedroom Kent semi that needs about 10,000 kWh of heat a year for heating and hot water. It assumes electricity at around 26p per kWh, gas at around 6.5p per kWh and a heat pump tariff averaging about 15p per kWh. These are illustrative figures only. Energy prices change every quarter under the Ofgem price cap, so check today’s rates.
| Heating system | Assumed efficiency | Fuel needed per year | Approx. cost, standard tariff | Approx. cost, heat pump tariff |
| Ground source heat pump | SCOP 4.0 | 2,500 kWh electricity | £650 | £375 |
| Air to water heat pump | SCOP 3.2 | 3,125 kWh electricity | £810 | £470 |
| High temperature air source heat pump | SCOP 2.8 | 3,570 kWh electricity | £930 | £535 |
| Modern gas boiler | 88% | 11,360 kWh gas | £740 | Not applicable |
| Electric storage or panel heaters | 100% | 10,000 kWh electricity | £2,600 | Not applicable |
One more saving often gets missed. If you switch fully to a heat pump and have your gas supply capped, you no longer pay the daily gas standing charge, which is worth roughly £100 to £120 a year at current rates.
Smart Tariffs for Heat Pump Owners
Smart heat pump tariffs are one of the easiest ways to cut running costs. Suppliers such as Octopus Energy, British Gas, EDF and OVO offer tariffs with cheaper rates at certain times of day. Your heat pump can be set to warm the house and heat the hot water cylinder during those cheaper windows, so you pay less without feeling any colder. Adding solar panels and a battery can bring costs down further still.
Tips to Keep Running Costs Low
- Leave it running steadily. Heat pumps are most efficient when they keep your home at a gentle, even temperature rather than blasting heat on and off like a boiler.
- Use weather compensation. This setting adjusts the water temperature to the weather outside, so the system never works harder than it needs to.
- Top up insulation first. Loft insulation, cavity wall insulation and draught proofing reduce the heat your home needs, so a smaller, cheaper system can do the job.
- Pick an MCS certified installer. Good design is the difference between a SCOP of 2.5 and a SCOP of 4, which can mean hundreds of pounds a year.
How Much Do the Different Types of Heat Pumps Cost to Install?
The different types of heat pumps cost anywhere from around £1,500 for a single room air to air unit to £35,000 or more for a ground source system with boreholes. For a typical Kent family home, a fully installed air to water heat pump usually costs £8,000 to £15,000 before the grant, which often brings it down to somewhere between £500 and £7,500.
| Heat pump type | Typical installed cost before grant | Boiler Upgrade Scheme grant | Typical cost after grant |
| Air to water air source | £8,000 to £15,000 | £7,500 | £500 to £7,500 |
| Ground source (horizontal loop) | £18,000 to £28,000 | £7,500 | £10,500 to £20,500 |
| Ground source (vertical borehole) | £25,000 to £35,000+ | £7,500 | £17,500 to £27,500+ |
| Hybrid | £6,000 to £10,000 | Not eligible | £6,000 to £10,000 |
| Air to air (per room, multi room systems cost more) | £1,500 to £4,000 | Check current rules | £1,500 to £4,000 |
These are typical industry ranges and your price depends on the size of your home, how much heat it loses, whether you need a new hot water cylinder or radiators, and how easy access is. The only way to know your true figure is a proper home survey and heat loss calculation, which we include free with every Guscott Heating estimate.
What Grants Are Available for Heat Pumps in Kent?
The grants available for heat pumps in Kent include the £7,500 Boiler Upgrade Scheme grant, 0% VAT on installation and, for eligible lower income households, local council funding. Together they make a heat pump far more affordable than most people expect.
Boiler Upgrade Scheme
The Boiler Upgrade Scheme (BUS) is run by Ofgem and gives £7,500 off the cost of an air source or ground source heat pump in England and Wales. Your installer applies on your behalf and the grant comes straight off your bill. To qualify:
- You must own the property, and this includes landlords and second home owners.
- The heat pump must replace a fossil fuel system such as gas, oil or LPG, or direct electric heating.
- The installer must be MCS certified.
- Your property needs a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation, unless you have a valid exemption.
0% VAT on Heat Pumps
Heat pumps and their installation are currently charged at 0% VAT in Great Britain until at least March 2027. On a £12,000 installation, that is a saving of £2,000 or more compared with the standard 20% rate.
Local Council Support
The government’s Warm Homes: Local Grant is delivered through participating local councils and can fund heat pumps and insulation for eligible lower income households in England. Funding and eligibility vary by area, so check with your district council, whether that is Maidstone, Swale, Thanet, Dover or elsewhere in Kent. Grant schemes change, and we always confirm what is available at the time of your survey.
Which Type of Heat Pump Is Best for Your Kent Home?
The best type of heat pump for your Kent home depends on the size and age of your property, how much outdoor space you have and what you heat with now. For roughly nine out of ten homes we survey, a standard or high temperature air to water heat pump is the right answer. Here is how it usually breaks down.
Terraced Houses and Flats
Air to water monobloc units work well on most terraced houses, as long as there is room for the outdoor unit in a back garden, yard or side return. This is common across Rochester, Gillingham and Dartford. For flats without outdoor space at ground level, an air to air system or, in new builds, an exhaust air heat pump may be more practical.
Semi Detached and Detached Homes
Air to water air source heat pumps are the natural fit here. There is usually plenty of space outside, and these homes are exactly what the Boiler Upgrade Scheme was designed for. Typical examples include family homes in Kings Hill, Snodland, Hythe and Swanley.
Rural and Off Gas Properties
Rural homes often have the most to gain. Thousands of Kent households, particularly in villages across the Weald, the North Downs and Romney Marsh, still rely on heating oil or LPG, which can be expensive and swing wildly in price. An air source heat pump removes fuel deliveries and storage tanks altogether.
We regularly install in areas around Headcorn, Marden, Wye and New Romney.
Period and Older Homes
Older homes can absolutely run on a heat pump, but they need careful design. A high temperature air source model, combined with sensible insulation upgrades, is often the best route for Victorian and Edwardian homes in Canterbury, Tunbridge Wells, Sevenoaks and the surrounding villages. A detailed room by room heat loss survey is essential here.
New Build Homes
Modern homes are very well insulated, so they need far less heat. A small air to water unit is usually ideal, and very airtight new builds may suit exhaust air heat pumps too. Under the Future Homes Standard, new homes in England are expected to move away from gas boilers, with heat pumps becoming the norm.
Ready to Choose the Right Heat Pump for Your Kent Home?
Finding the right heat pump for your home starts with a free, no-obligation online estimate from Guscott Heating. Every property has different heating requirements, so choosing the right system depends on factors such as your home’s size, insulation and existing heating setup.
Request your free online heat pump estimate from Guscott Heating today and discover the options for a warmer, more energy-efficient home.
Our team can assess your property’s needs, explain the available options and help you understand the installation costs, including how the £7,500 Boiler Upgrade Scheme grant could reduce the amount you pay, subject to eligibility.
Guscott Heating provides expert air source heat pump installation across Kent and the wider South East of England, helping homeowners and landlords find energy-efficient heating solutions suited to their properties.
Whether you are replacing an existing gas or oil boiler or planning ahead for future rental property energy-efficiency requirements, our MCS-certified team is here to help you make an informed decision.
Frequently Asked Questions
Do I Need Planning Permission for a Heat Pump in Kent?
Most air source heat pumps in England do not need planning permission, because they count as permitted development. The unit must meet certain conditions, including the MCS noise standard, and rules introduced in 2025 removed the old requirement to keep units at least 1 metre from your boundary. Listed buildings and homes in conservation areas, such as parts of central Canterbury, Faversham and Sandwich, may need consent from your local council, so we check this during your survey.
Are Heat Pumps Noisy?
Modern air source heat pumps are quiet. Most produce around 40 to 55 decibels close to the unit, which is similar to a fridge humming or a quiet conversation. To qualify as permitted development, the noise level at your neighbour’s nearest window must be no more than 42 decibels, and we plan the position of your unit with this in mind.
How Often Does a Heat Pump Need Servicing?
A heat pump should be serviced once a year, just like a boiler. Most manufacturers require an annual service to keep the warranty valid, and it typically costs around £100 to £200. In between, all you need to do is keep leaves, snow and garden clutter away from the outdoor unit so air can flow freely.
Can I Keep My Gas Hob if I Get a Heat Pump?
You can keep a gas hob or gas fire after fitting a heat pump, and you will still be eligible for the Boiler Upgrade Scheme as long as the heat pump replaces your gas boiler. The only downside is that you will keep paying the daily gas standing charge, so some homeowners choose to switch to an induction hob at the same time and remove the gas supply completely.
What Happens to a Heat Pump in a Power Cut?
A heat pump stops working during a power cut, but so does a modern gas boiler, because both need electricity to run their pumps and controls. The good news is that a well insulated hot water cylinder keeps water hot for many hours, and your home holds onto its warmth for a while too. When the power returns, the heat pump restarts by itself.
