Are high-temperature heat pumps worth it in the UK? Which models are best? In this guide, we tackle these key questions to help you choose the right option for your home.
In line with the UK's ambitious carbon-neutral objectives, the government aims to install 600,000 domestic heat pumps across the nation by 2028.
However, the installation of standard low-temperature heat pumps often proves impractical for many homes without significant and costly upgrades.
Enter high-temperature heat pumps—a promising alternative recommended by the Committee on Climate Change for their pivotal role in the UK's transition to net zero.
These devices operate with efficiencies comparable to traditional gas boilers and represent a practical solution for many households facing retrofit challenges.
This guide explores the mechanics of high-temperature heat pumps, examining their operational costs and other essential considerations potential owners should know.
Whether you're exploring eco-friendly heating solutions or planning to upgrade your home's energy system, understanding the benefits and implications of high-temperature heat pumps is crucial.
Ready to make your home more energy-efficient and cut down on your heating bills? Get a heat pump quote today from our trusted partners at Heat Geek here.
What is a High-Temperature Heat Pump?
High-temperature heat pumps are essentially supercharged versions of your regular heat pumps.
Instead of capping out at the usual 45°C to 55°C, these powerhouses can crank the heat up to an impressive 60°C to 80°C.
This makes them a game-changer for older buildings where upgrades for efficiency aren't always practical.
What's their secret? They leverage cutting-edge refrigerants like R290 or R32 and utilise advanced compressor technologies to hit these higher temperatures.
Now, you might think, "Higher temperature, lower efficiency, right?" Nope!
These high-temperature heat pumps match the efficiency of the lower-temperature cousins, and even better—according to a recent government report, they're three times more efficient than traditional boilers.
Interested to learn how heat pumps compare to gas boilers? Check out our complete heat pump vs gas boiler guide.
How Efficient Are High-Temperature Heat Pumps?
“
When considering the efficiency of heat pumps, a critical metric to understand is the Coefficient of Performance (COP). This figure represents the average efficiency of a heat pump over 12 months.
PS You can watch our Heat Pump Case Study in the video below:
Modern heat pumps generally feature a COP ranging from 2 to 4, with the exact value depending on the specific type of heat pump installed.
Ground source heat pumps, for example, often achieve the highest COP because of their ability to maintain consistent temperatures from the heat stored underground.
This ratio means that for every unit of electricity used, the heat pump produces between 2 to 4 units of heat energy. It's an effective way to gauge how much bang you're getting for your buck in terms of energy use.
However, it’s important to note that a heat pump's efficiency isn't constant; it varies with the seasons. In winter, when higher temperatures are needed to heat homes, heat pumps tend to operate less efficiently.
Conversely, during the milder months of spring and autumn, efficiency increases as lower temperatures are required to keep homes comfortable.
Understanding these fluctuations can help you optimise your heat pump's performance and manage energy consumption more effectively throughout the year.
How Do High-Temperature Heat Pumps Work?
So how do high-temperature heat pumps work in comparison to their regular counterparts?
There are a few major ways employed that allow them to operate at higher temperatures, including the following strategies:
Enhanced Vapour Injection (EVI)
EVI, or Enhanced Vapor Injection, takes the heat pump game to the next level by adding an extra loop to the standard heat pump cycle.
This genius modification allows a small amount of condensed refrigerant to escape through an expansion valve directly into a counterflow heat exchanger.
The result? A superheated vapour is then injected back into the compressor, supercharging the heating capacity.
Sure, it uses a bit more electricity, but the payoff is huge: a significant boost in the machine's efficiency.
This clever tweak was pioneered by the sharp minds in the HVAC industry, who continuously innovate to push the boundaries of what heat pump technology can achieve.
With EVI, they've hit a home run, making it a powerhouse in both performance and efficiency.
Advanced Refrigerants
In the context of heat pumps, a refrigerant is a substance used to absorb and transfer heat from one place to another.
It's essentially the lifeblood of a heat pump system, playing a critical role in the heating and cooling cycles.
In low-temperature heat pumps, the efficiency of the heat pump decreases in direct correlation with the temperature of the refrigerants i.e. the higher the temperature, the less efficient it becomes.
However, high-temperature heat pumps use novel refrigerants that are better able to maintain their efficiency at higher temperatures.
Two Cascade Systems
A cascade system in a heat pump refers to an arrangement where two distinct refrigeration cycles (typically involving different refrigerants) are connected in series through a heat exchanger.
This setup is particularly useful for achieving very low or very high temperatures, which are beyond the capability of a single refrigeration cycle.
For example, the heat will move to the evaporator, which will then result in the second refrigerant evaporating. In turn, the second refrigerant then condenses at a still relatively low pressure, keeping the output high.
Pros and Cons of High-Temperature Heat Pumps
Here are the major advantages and disadvantages of high-temperature heat pumps:
Pros of High-Temperature Heat Pumps:
No New Radiators or Insulation Required: Installing these systems doesn't necessitate the installation of new radiators or upgrading your existing insulation.
High Efficiency Levels: These units maintain efficiency levels comparable to other heat pumps on the market.
Superior to Boilers in Efficiency: They surpass traditional boilers in terms of energy efficiency.
Eco-Friendly: They are more environmentally friendly compared to boilers, reducing your carbon footprint.
Cons of High Temperature Heat Pumps:
Higher Initial Cost: Typically, they are more expensive to purchase than standard heat pumps.
Operational Costs: While currently more costly to operate than gas boilers, this may change as energy prices fluctuate and technology advances.
Increased Weight: These systems are heavier than their standard counterparts, which may complicate installation and placement.
One of the refrigerant high-temperature heat pumps used is R290, essentially propane.
Propane is a heavy gas and highly explosive. R290 heat pumps need to be sited away from drains, grids or enclosed areas as if the unit leaks, the gas stays local and if someone flicked a cig but, it could cause an explosion. This can limit this application or suitability.
Propane is a gas which is captured during the refining process of heavy oils. So it’s not the cleanest although, it's better than burning gas day after day. And Propane features a drastically lower global warming potential than R-404A, R-22, and R-134A so in the world of heat pumps it’s a cleaner alternative.
R290 systems are required to operate at very high pressure, meaning the cost of the production and the end product are more expensive.
High-Temperature Heat Pump Costs
One significant drawback of high-temperature heat pumps is their initial cost, which is considerably higher than that of standard low-temperature heat pumps.
Prices vary based on the brand and size of the unit, but typically range from £12,000 to £44,000, compared to £2,400 to £14,000 for conventional heat pumps.
However, it's crucial to consider the long-term financial benefits: high-temperature heat pumps often have lower operating costs.
This aspect should be included in your overall financial calculations.
Additionally, an advantage of high-temperature heat pumps is that they usually don't require upgrades to your existing radiators or insulation—a requirement often associated with installing regular heat pumps.
This factor can also contribute to overall cost savings and convenience.
More heat pump guides:
Should You Install A High-Temperature Heat Pump?
A high-temperature heat pump is well-suited for most properties in the UK.
However, due to the higher cost associated with these systems, they are particularly favoured by homeowners who find it impractical to make the extensive upgrades necessary for operating a standard heat pump.
Ideal scenarios for high-temperature heat pumps include listed buildings, which often have strict renovation restrictions and off-grid homes where proper insulation may be challenging to implement.
It’s important to note that regardless of the heating system you choose, investing in proper home insulation is beneficial. Insulating your home effectively can lead to significant time and cost savings in the long run.
Which High-Temperature Heat Pumps Are Available?
The availability of high-temperature heat pumps is not as widespread in terms of the number of brands currently offering them.
In the UK at present, the following models are offered:
Brand | Heat Pump Model | Key Features | SCOP Rating | Price Range* |
Daikin | ETBH Altherma 3 H HT Indoor Unit 14kW to 18kW | High-Quality Casing, Three-Layer Insulation, And Bizone Settings | 3.58 to 4.81 | £4,000 to £6,300 |
Trianco | Activair High-Temperature Heat Pump 9kW to 22kW | Anti-Frost Protection, Wi-Fi Immersion Control, And Relatively Lightweight | -N/A | £4,080 to £6,240 |
Vaillant | Arotherm Plus | Can Operate In Extreme Frost And Temps Of Up To 75°C | Up to 5.03 | £3,400 to £6,500 |
Samsung | HT Quiet (HTQ) | Very Low Sound Levels, Hybrid Capacity | 3.53 to 4.68 | £3,900 to £5,600 |
Table updated May 2024.
Get A Quote From Us Today
Without boasting, get your new heat pump quote and buy from us, here’s why:
Gas Safe installation within 24 hours.
Thousands of happy customers – an average score of 4.9 on Trustpilot (that’s better than the market leader).
Price match guarantee – if you find a cheaper quote, we will match (must be like for like).
Multiple payment options - interest-free available.
10-year guarantee.
Fixed price guarantee – no hidden costs.
Save your quote until later.
Use this clickable form to get a fixed price on the screen instantly.
Heat Happy.
