Thinking about getting an air source heat pump, but wondering about the real costs? It's not just about the installation costs, you also need to know about running costs, maintenance, and any other potential expenses.
Welcome to the Heat Pump Gang guide to the cost of air source heat pumps, where we provide all the information you need.
How Much Does An Air Source Heat Pump Cost?
We'll begin with the heat pump installation cost before moving on to other areas of interest.
Air source heat pump costs vary depending on the model you choose, as there are two basic air source models:
Explore: What Is An Air Source Heat Pump?
Air-To-Water Heat Pumps
Air-to-water heat pumps act like a heat sponge, absorbing warmth even from chilly outside air. They use a special fluid (refrigerant) that circulates through the system. This fluid can pick up heat even at low temperatures.
This is how these ingenious devices work:
- Transferring heat - Once the refrigerant absorbs heat from the outdoors, it's pumped to a compressor which acts like a booster, significantly raising the temperature. This hot refrigerant then passes through a heat exchanger, transferring the heat to a separate water circuit.
- Distributing warmth - This heated water then becomes the heart of your central heating system. It can be circulated through your existing radiators or underfloor heating, warming your home efficiently.
- Hot water - Many air-to-water heat pumps also have a built-in hot water storage tank. This means the same system that heats your home can also heat the water for your taps, showers, and baths, making it a true one-stop shop for climate control.
Air-To-Air Heat Pumps
These heat pumps offer a more focused approach to heating, particularly suited for specific situations.
If you have a smaller property or limited outdoor space for an additional unit, they can be a good option. They typically require just one outdoor unit.
Instead of using a water-based central heating system, air-to-air pumps work similarly to a reverse air conditioner. They extract heat from the outside air and transfer it directly into your home through a network of ducts. This blows warm air into designated rooms or zones.
Keep in mind...
- Duct dependency - Unlike air-to-water pumps that work with existing radiators, these systems might require the installation of ducts if your home doesn't already have them. This can be an additional cost to consider.
- Hot water source - Air-to-air units don't provide hot water. You'll need a separate system like an immersion heater or combi boiler to handle hot water needs.
- Climate considerations - While efficient, these pumps can be less effective in very cold weather as there's less heat to extract from the outside air.
- Insulation - A heat pump releases the heat at a lower rate than a gas boiler, and takes longer to do so. This means you need radiators with larger surface areas and/or adequate insulation to keep in the warmth your heat pump generates. This may add to the overall cost if you need to upgrade these aspects.
So, how much does each one cost? Let's take a look:
- Air-to-water heat pump - You can expect to pay somewhere between £8,750 and £14,050 for the unit and installation.
- Air-to-air heat pump - These are generally cheaper, with a range of £2,400 to £8,800 for the unit and installation (they only provide heating and cooling, but can't be connected to your central heating system to provide hot water).
These prices typically don't include any additional costs for upgrading your existing heating equipment to work with the heat pump, like installing underfloor heating for an air-to-water system or ducts for an air-to-air unit.
Other Factors Affecting Heat Pump Costs
So, we have a rough idea of the cost of air source heat pump installations, and we've hinted that there might be other factors to consider.
Now let's examine these in detail to see how they could impact the overall price you pay...
Unit Size
- Heat output (kW) - ASHP size is measured in kilowatts (kW) of heat output, which reflects its ability to warm your home. Larger properties with more rooms or higher heat requirements will need a larger (and pricier) heat pump unit.
- Rough cost impact - A typical 6kW air-to-water heat pump might cost around £3,000 to £4,000, while a larger 12kW unit could range from £4,500 to £6,000.
It's vitally important to select the right size heat pump for the space, as this affects energy efficiency and overall running costs.
Brand And Features
- Brand reputation - Established brands with proven track records might cost slightly more than lesser-known ones.
- Features - Features like inverter technology (for better efficiency), built-in hot water storage, or remote-control capabilities can add to the cost.
- Rough cost impact - The brand and specific features you choose can add or subtract a few hundred pounds from the base unit price.
Installation Complexity
- Pipework lengths - The length of pipework needed to connect the outdoor unit to your existing heating system can impact labour costs. Longer runs will require more work.
- Existing heating system - If your current system requires significant modifications to work with the ASHP (you may need to install underfloor heating for air-to-water pumps), expect additional costs.
- Ductwork (air-to-air only) - Installing a network of ducts for air distribution in an air-to-air system can be a significant cost factor, especially if your home lacks existing ductwork.
- Rough cost impact - Basic installations might only add a few hundred pounds, while complex setups involving extensive pipework or ductwork installation could add several thousand pounds.
Here's an example to illustrate the cost variations...
Imagine two similar three-bedroom homes:
- House A. This house has a well-maintained boiler system with existing radiators and a relatively short distance between the outdoor unit placement and the central heating connection point. They choose a basic 8kW air-to-water heat pump with a good reputation but no fancy features.
- House B. This house has an older, less efficient boiler system and requires underfloor heating to be installed to work with the ASHP. The chosen location for the outdoor unit necessitates longer pipework runs. They opt for a top-of-the-line 12kW air-to-water heat pump with inverter technology and smartphone control.
Estimated Costs:
- House A: Unit cost: £3,500 + Installation: £1,500 = £5,000 total (approx.)
- House B: Unit cost: £6,000 + Installation: £4,000 (including underfloor heating) = £10,000 total (approx.)
Remember, these are just 'ballpark' figures. As an MCS-certified installer, Heat Pump Gang will consider your specific property and needs to give you a more accurate picture of the total cost.
A Heat Pump Grant
There's no escaping the fact that these prices will put some homeowners off the idea of buying an air source heat pump system.
If this is how you feel, help may be at hand with the Boiler Upgrade Scheme (BUS), which provides £7,500 towards installation costs. And can be used against the cost of ground source heat pumps and (in some cases) biomass heaters as well as air source heat pumps!
However, the BUS grant is limited to residents in England and Wales. Property owners in Scotland can receive the same amount for heat pump installation through Warm Home Scotland.
Dig deeper: Air Source Heat Pump Grants
Are Air Source Heat Pumps Expensive To Run?
While air source heat pumps boast impressive efficiency, their running costs depend on several factors. Here's a detailed breakdown to help you compare them with gas boilers and electric heating systems:
Air Source Heat Pump Running Costs
- Efficiency Matters - Unlike a gas boiler that burns fuel to generate heat, ASHPs move existing heat from outside air. Their efficiency is measured by a Coefficient of Performance (CoP). A higher CoP signifies the pump can move more heat for each unit of electricity it uses. For example, a CoP of 3 indicates the pump delivers 3 units of heat for every 1 unit of electricity consumed.
- Electricity Prices - The cost of electricity directly impacts running costs. Off-peak electricity tariffs can significantly lower costs compared to standard rates.
- Climate Impact - ASHP efficiency can be affected by outside temperatures. In colder weather, the pump needs to work harder to extract heat, potentially increasing electricity usage.
Estimating ASHP Running Costs
It's not a simple calculation! Several factors at play make it challenging to give a one-size-fits-all answer.
However, let’s give it a go...
- Estimate your heat demand - This depends on your property size, insulation levels, and climate.
- Choose a realistic CoP - Consider your expected average outside temperatures and choose a CoP that reflects real-world performance (e.g., 2.5 to 3.0 for moderate climates).
- Multiply heat demand by electricity cost - Multiply your estimated heat demand (kWh) by your electricity unit price to get the base cost.
- Factor in CoP - Divide the base cost by the chosen CoP to see the potential reduction due to ASHP efficiency.
Here’s an example to illustrate what we mean:
- A house with a moderate heat demand of 12,000 kWh per year
- Electricity cost - £0.18 per kWh
- CoP 2.75
In this case, the base cost is 12,000 kWh multiplied by £0.18/kWh, which equals £2,160, giving a running cost of approximately £785 per year.
To put this in perspective, the average household
How Do They Compare With Gas Boilers And Electric Heating?
To understand the true value of investing in an air source heat pump, we need to compare the running costs with those of traditional heating systems.
So, let's take an honest look at the facts to offer a practical and helpful analysis...
Gas Boilers
- Fuel Cost Advantage - Currently, natural gas is generally a cheaper fuel source per unit compared to electricity in the UK. This can give the gas boiler a bit of a head start in terms of upfront running costs.
- Efficiency - However, the traditional gas boiler isn't a perfect option! They typically have an efficiency rating of around 90%, which means that for every 10 units of energy in the gas they burn, roughly 1 unit escapes as waste heat goes up the flue. In comparison, heat pumps boast efficiency levels of between 300 and 500%. Some newer models are pushing around 600%!
- Hidden Losses - While gas might be cheaper per unit, those efficiency losses can add up. With an ASHP, even with a CoP lower than 3, you're potentially moving more than 3 units of heat for each unit of electricity used, making it more efficient overall.
- Energy Prices - Another factor to consider is the volatility of gas prices, which can fluctuate significantly, impacting annual energy bills over time. ASHPs, while reliant on electricity prices, might offer more stability in running costs due to their high efficiency levels.
Electric Heating Systems
- Straight Conversion, Lower Efficiency - Traditional electric heating systems like storage heaters are generally less efficient than ASHPs. These systems work by converting all the electricity they use directly into heat, with no additional efficiency gains.
- Simple but Costly - While they might be simpler to install initially, their lack of efficiency can translate to higher running costs compared to ASHPs.
Other Considerations
- Maintenance Costs - A gas boiler requires regular servicing to maintain peak performance and will last about 15 years. You'll need to get your heat pump serviced (see below for costs) every one or two years to keep it perfectly tuned and energy efficient. With few moving parts, your heat pump shouldn’t need a lot of maintenance and will generally last between 20 to 30 years. You can help keep it in good condition by cleaning the filter and keeping the heat pump's fans free from debris.
- Government Grants - A significant factor tipping the scales in favour of ASHPs is the availability of government grants in the UK. These grants can help offset a large portion of the upfront installation cost, making ASHPs a more financially attractive option in the long run.
Heat Pump Service Costs
To get the most from your air source heat pump, it's vital to keep it tuned and running efficiently. Any drop-off in performance will cause the system to work overtime, pushing up your energy bills.
A full service should be carried out by a professional heat pump technician at least once every couple of years and will cost between £150 and £300.
The service should include the following:
- General inspection
- Lubrication of parts
- Thermostat check
- Refrigerant replacement (if required)
- Replacement of any small parts
- Check for leaks
- Pressure check
- Large component check
- Electrical safety check
High Electricity Bill With An Air Source Heat Pump?
This problem has been reported by some consumers who've made the switch from gas and oil boilers to air source heat pumps.
A typical heat pump operates better and more efficiently in the warmer months. However, it has to work harder in the winter because of the cooler air temperature, meaning that it uses more electricity. When it's really cold, the unit will go into defrost mode, and energy is used in trying to defrost the heat pump.
As the kWh price for electricity is higher than gas (at the moment!), your energy bills may rise during the cooler months.
The best way around this is to ensure that you choose a reputable, professional heat pump installer to fit and fine-tune the system and get your heat pump functioning efficiently. As the air temperature fluctuates, the system will adjust itself accordingly, although efficiency will always be impacted by severe cold weather to some extent.
You might also consider installing a ground source heat pump, as these rely on the more stable, constant temperatures below ground level.
Alternatively, a hybrid system could be the answer, as you have the option of switching from the heat pump to a gas boiler if or when necessary.
High Temperature Heat Pumps
Standard air source heat pumps typically operate in a range of 40-55°C (104-131°F). This works well in many cases, but some homes might require hotter water for radiators or underfloor heating designed for a traditional gas boiler.
High temperature heat pumps can reach temperatures of 60-80°C (140-176°F). This higher heat output allows them to function effectively with existing heating systems designed for hotter water, eliminating the need for expensive upgrades like installing new radiators.
Benefits Of High Temperature Heat Pumps
- Compatibility - They can work seamlessly with existing radiators and underfloor heating systems designed for higher temperatures, potentially saving you money on modifications.
- Faster Heating - These heat pumps can heat your home quicker compared to standard ASHPs, especially in colder climates.
- Reduced Reliance on Electric Heating Boosters -Some traditional ASHPs might use electric heating elements as a backup when they struggle to reach desired temperatures. High temperature models can potentially reduce the need for such backup systems.
Even so, they are generally more expensive to fit, and they are less efficient (around 250%) than other types of heat pumps. This potentially means higher costs for daily use, which relates to our problem in the previous section.
However, the technology is very new, and these heat pumps are rare in the UK at the moment. Hopefully, they will be perfected and improved in time.
As with all heat pumps, it's essential to discuss your options with a professional, like Heat Pump Gang.
Gain insights: Advantages And Disadvantages Of Air Source Heat Pumps
Are Air Source Heat Pumps Worth The Investment?
At Heat Pump Gang, we firmly believe that the answer is yes!
If you're serious about reducing your carbon footprint and ending your reliance on fossil fuels, it's well worth exploring the different heat pumps available.
Heat Pump Gang has a proud record of assisting homeowners in this process, offering professional advice on renewable energy technology and the installation of heat pumps of all kinds.
While the installation costs might seem high, the long-term benefits are immeasurable.
We believe that heat pumps are contributing to a brighter, more sustainable future for all, where energy doesn't cost the Earth.
