Notice

Raising product standards for space heating: policy proposals

Updated 18 December 2024

This notice was withdrawn on 18 December 2024

On 17 December 2024, we launched a consultation on the detailed proposals.

See Raising product standards for space heating.

Introduction

Improving heating appliance efficiency can deliver significant consumer bills savings – by reducing energy consumption – also leading to reduced carbon emissions and increasing energy security by reducing dependence on volatile fossil fuel energy markets.

The government has developed a range of proposals, on which we will soon be consulting, which will drive significant improvements in the efficiency of new heating appliances and deliver substantial bill savings for households purchasing gas boilers and heat pumps.

The new energy efficiency proposals for gas boilers are expected to deliver average bill savings of over £30 per year from 2028. In advance of this, the first tranche of proposals are expected to see gas boiler households benefit in a £19 yearly saving. These savings quickly offset the increased capital costs of approximately £50, delivering a total net saving of £400 over the 15-year life of the boiler (undiscounted), leading to a net saving of £26 annually (after applying a 3.5% discount rate).

Heat pumps running costs can be similar or higher than gas boilers, despite being 3 times more efficient, because they use electricity rather than gas. To assist with heat pump running costs, the consultation will set out new heat pump efficiency proposals which expect to deliver a bill saving for households of around £22 per year from 2029. These savings are expected to quickly offset the estimated increased capital costs of £56 – delivering a net saving for households of around £20 per year over an 18-year typical lifespan of a heat pump.

There are some heating appliances already available which meet our proposed requirements, meaning consumers can reap the benefits from these efficient products now. And some manufacturers may choose to streamline their product lines early, helping more consumers to benefit from bill savings before 2026.

The United Kingdom (UK) is committed to net zero greenhouse gas emissions by 2050. This will require significant transformation to decarbonise heating, which accounted for 22% of the UK’s carbon emissions in 2022. Our analysis estimates that our proposals will also contribute to the equivalent carbon savings of 2.0 million tonnes (MtCO2e) for Carbon Budget 5 (which covers 2028 to 2032), and up to 3.8MtCO2e for Carbon Budget 6 (which covers 2033 to 2037). 

To realise these benefits, we are proposing to update ecodesign and energy labelling regulations for space and combination heaters. Ecodesign legislation has historically been an effective way of reducing energy consumption by driving higher performance of energy-related products. It has achieved this by preventing less efficient products from being placed on the market through new minimum efficiency standards, driving innovation by setting benchmarks for the highest standards of products and introducing a compliance regime delivered through market surveillance authorities. Accompanying energy labelling legislation has also improved the clarity and consistency of consumer information, supporting effective choice and competition.

These proposals aim to:

• enable electrification of heat
• reduce fossil fuel demand
• ensure effectiveness of product standards
• improve energy labels

A consultation setting out detailed proposals will be published alongside a draft statutory instrument and options assessment next month. These proposals go beyond the present requirements of ecodesign legislation (2013/813) and energy labelling legislation (2013/811) to further upgrade the efficiency of space heating products. These proposals build on the research and evidence gathered through the Improving Boiler Standards and Efficiency consultation^{[footnote 1]}, Boiler Plus Standards review^{[footnote 2]}, and Energy-related products: call for evidence^{[footnote 3]}

The Office for Product Safety and Standards (OPSS), within the Department for Business and Trade (DBT), is the appointed Market Surveillance Authority for ecodesign and energy labelling regulations in Great Britain and will provide oversight for implemented proposals. 

The proposed updates to ecodesign and energy labelling, that will be set out in the consultation, would apply to GB. To facilitate dual access to both the UK Internal Market and the EU Single Market, Northern Ireland continues to apply EU ecodesign and energy labelling regulations in accordance with the Windsor Framework. As the UK government is looking to introduce higher requirements in GB than the current standards applicable in Northern Ireland, goods compliant with these higher requirements will also be able to be placed on the market in Northern Ireland. At the same time, Northern Ireland businesses will continue to have unfettered access to the GB market. Accordingly, the proposals set out here will not inhibit trade between Great Britain and Northern Ireland.

We are aware that since 2018 the European Commission has been reviewing and planning to update the EU’s ecodesign and energy labelling legislation for hydronic space heaters. We will continue to give due consideration to this work as it develops.

Enabling electrification of heat

Heat pumps have a critical role to play in decarbonising how we heat our homes. The government is committed to supporting the growth of the heat pump market.

It is also crucial that the heat pumps installed into homes deliver for consumers and keeps bills as low as possible. This requires pushing the market to ensure they are as efficient as possible. This has the added benefit of ensuring electricity demand is low. Due to developments in heat pump technology, it is clear that heat pumps are capable of achieving much higher efficiencies than the ecodesign legislation currently requires. To enable the electrification of heat, we will consult on proposals to:

• update the primary energy factor for electricity to 1.9 (from 2.5)
• amend and introduce definitions of low-, medium- and high-temperature heat pumps and increase and introduce minimum efficiency requirements for each temperature
• create a new definition for a hybrid heat pump and introduce minimum efficiency requirements for hybrid heat pumps

Updating the primary energy factor for electricity, used to calculate seasonal space heating energy efficiency for space heaters

Ecodesign and energy labelling regulations use seasonal space heating energy efficiency, which is calculated by adjusting the seasonal coefficient of performance (SCOP) to account for primary energy. The conversion coefficient (CC) acts as a primary energy factor for electricity. Currently CC = 2.5, but is not reflective of electricity production in GB in 2024, given the decarbonisation of the electricity grid over the last decade. Updating the primary energy factor for electricity will help ensure the carbon benefits of using efficient electric space heating technologies, such as heat pumps, are properly recognised.

Updating heat pump definitions

To improve consistency and comparability we propose to update the definitions of low-temperature heat pump, low-temperature application and medium-temperature application, and introduce complementary definitions for medium-temperature and high-temperature heat pumps.

• ‘low-temperature heat pump’ means a heat pump space heater, or heat pump combination heater, that is declared capable of being used in a low-temperature application.
• ‘medium-temperature heat pump’ means a heat pump space heater, or heat pump combination heater, that is declared capable of being used in a medium-temperature application
• ‘high-temperature heat pump’ means a heat pump space heater, or heat pump combination heater, that is declared capable of being used in a high-temperature application
• ‘low-temperature application’ means an application where the heat pump heater delivers heating at an indoor heat exchanger outlet temperature of 35°C at reference design temperature, and at the water outlet temperature specified per part load condition
• ‘medium-temperature application’ means an application where the heat pump heater delivers heating at an indoor heat exchanger outlet temperature of 55°C at reference design temperature, and at the water outlet temperature specified per part load condition
• ‘high-temperature application’ means an application where the heat pump heater delivers heating at an indoor heat exchanger outlet temperature of 65°C at design temperature, and at the water outlet temperature specified per part load condition

Updating heat pump minimum efficiency requirements

Products cluster near the current minimum requirements as it is cheaper to produce less efficient products. Market forces will drive products to the cheaper end, at a long-term cost to the consumer society from energy consumption. Therefore, government must intervene to increase the minimum efficiency requirements to ensure consumers are not paying higher bills due to purchasing less efficient products than the market is capable of producing.

We are proposing these efficiency levels as we know that manufacturers can produce more efficient products; in most cases a manufacturer will be producing multiple products with different efficiencies at the same production site. These proposals have been selected to remove the least efficient ~40% of the market in the first tranche of changes. This approach has been shown to maximise energy savings, while also not leaving gaps in either the product types available on the market, or leaving manufacturers unable to switch to a viable product. In most cases manufacturers are already producing compliant products, it is a matter of reprioritising production. We anticipate that the lead-in time for implementation should allow manufacturers time to adjust their production.

We propose updating the following minimum seasonal space heating energy efficiencies

• for low-temperature heat pumps (tested at 35°C) – from current requirement of 125% (based on CC=2.5) to 170% in mid-2027 and 175% in mid-2029 (based on CC=1.9), equivalent to heat pumps with SCOPs of 3.29 and 3.38, respectively
• for medium-temperature heat pumps (tested at 55°C) – from current requirement of 110% (based on CC=2.5) to 168% in mid-2027 and 175% in mid-2029 (based on CC=1.9) equivalent to heat pumps with SCOPs of 3.25 and 3.38, respectively
• for high-temperature heat pumps (tested at 65°C) – 143% in mid-2027 and 153% in mid-2029 (based on CC=1.9), equivalent to heat pumps with SCOPs of 2.77 and 2.96, respectively

Where a heat pump can operate at more than one temperature application, we propose that the heat pump will be required to be tested at all relevant temperatures and meet the corresponding Minimum Energy Performance Standard (MEPS) at each temperature. The heat pump heater and temperature application definitions are worded to require this.

Hybrid heat pump requirements

Defining hybrid heat pumps, such that they are required to have similar characteristics and capabilities, can improve clarity, consistency and comparability between products for consumers. Current ecodesign (2013/813) and energy labelling (2013/811) legislation does not include a definition of hybrid heating systems. Without one, we will not be able to set minimum efficiency requirements and there is a risk of miscommunication and green-washing, as a range of products could be described as a ‘hybrid heat pump’.

We have identified a number of key elements to a definition:

• Any legislative definition needs to be easy to understand and apply so that manufacturers can easily determine whether their product, or group of products, would fall in- or out-of-scope of this definition
• An array of hybrid heat pumps is currently available. So as not to hinder innovation, or create loopholes in our minimum requirements, we need a definition which can encompass this wide variety of products
• We intend to include in the definition any elements of a hybrid heat pump which are essential to the effectiveness of the system, such as a single master control to operate and optimise how the component heat sources operate together. This definition would, therefore, set the bar as to what a hybrid heat pump needs to contain or be capable of.
• New types of hybrid heat pumps, not currently widely available, may enter the market and/or have a significant role to play in heat decarbonisation in the future. We need to ensure our definition is broad and flexible enough to encompass new innovations.

We, therefore, propose that a hybrid heat pump system means a system of space heating, or space and water heating, that contains an electric heat pump, another heater which is not an electric heat pump, and a master control which determines, based on operating conditions, the heat output of each of the heaters.

Setting a MEPS for hybrid heat pumps through ecodesign (2013/813) is an important step in creating a solid foundation for a market for hybrid heat pumps and preventing low efficiency products from being placed on the market in the future. As there is still a relatively small existing market for hybrid heat pumps, we are also mindful that any new MEPS need to avoid stifling this emerging market by setting too high standards too early. We, therefore, propose introducing minimum efficiency requirements for hybrid heat pumps at medium-temperature application (55°C) of 125% (based on CC=1.9) from mid-2027.

Reducing fossil fuel demand

Despite the range of government policies aimed at growing the clean heat market, it is estimated that there will still be over 10 million new boiler installations over the next decade. We want to ensure that consumers purchasing these new fossil fuel boilers can benefit from raised in-home performance.

Despite being a mature technology there is more that can be done to ensure that condensing boilers operate as efficiently as possible while ensuring consumer comfort and control. The government aims to ensure households that still use fossil fuel system get energy bills as low as possible. The more efficient the operation of the fossil fuel system the lower consumer bills and the less carbon will be emitted.

Boiler Plus

In 2018, changes were made to Approved Document L of the English Building Regulations intended to improve the in-situ efficiency of boilers. The aim was to improve consumer comfort and ensure they benefit from increasingly energy efficient heating systems. These changes became known as the ‘Boiler Plus Standards’. The standards applied to boiler replacements and installations in existing dwellings.

According to these standards, when replacing any type of oil and gas boiler, installers should fit boiler interlock and a time and temperature control. There are additional standards for installations of gas boilers: an efficiency requirement for gas boilers of 92%, and, for combination gas boilers, a standard for 1 of 4 additional energy efficiency measures:

• Flue Gas Heat Recovery Systems (FGHRS)
• Weather Compensators
• Load Compensators
• Smart controls with automation and optimisation functions

With the exception of FGHRS, these measures are types of heating control that are intended to reduce gas consumption either by reducing the boiler’s operating time/periods or helping the boiler operate using lower flow temperatures.

The Boiler Plus Review (2021) was intended to check the levels of compliance with and impacts of the Boiler Plus standards.

The review found the standards had been successful in removing the lowest tested efficiency boilers from the market. There had also been a significant increase in the additional energy measures being installed with gas combination boilers in particular smart controls. The review did, however, also highlight several barriers to the delivery of the policy objectives and suggested ways in which policy could develop further. For example, there were concerns of potential non-compliance due to the lack of monitoring around the installation of additional energy measures with gas combination boilers. A consumer engagement gap was also raised due to limited awareness of temperature control functions and of the Boiler Plus standards. As the functions of temperature controls vary, so do the benefits to consumers. These benefits can be further impacted due to the operational protocols that are in place within both the boiler and the control, as these can affect the control’s ability to communicate with and adjust the boiler output.

Building on the findings of the Boiler Plus Review and previous consultations, to reduce fossil fuel demand, we will consult on proposals to:

• require all gas combination boilers (≤45kW) to be able to modulate their maximum output down to 15% without on/off cycling by mid-2028
• require all larger domestic-scale combination boilers (32≤45kW) to be able to modulate their maximum output down to 10% without on/off cycling by mid-2028
• require all combination boilers to be supplied with a 60°C low flow temperature factory default setting by mid-2026
• raise GB requirements so that temperature control Classes I-III are no longer sufficient by mid-2026
• require all temperature controls and gas combination, system and regular boilers to use open protocols by mid-2026
• require boilers and temperature controls, when placed on the market, to be accompanied by information about which open protocols they can use
• introduce temperature control Classes I-VIII definitions into the regulations
• require all temperature controls and oil combination boilers to use open protocols by mid-2028

Boiler modulation to tackle oversizing

Combination boilers are the most common boiler type sold on the UK market, making up around 80% of all gas boiler sales and large portion of oil boilers. These boilers tend to be attractive to consumers as they can meet hot water demand instantly and do not require a hot water tank, saving on space.

Correct boiler sizing is a significant factor in ensuring that household energy demands are met for space heating and domestic hot water. However, the anticipated hot water demand can heavily influence the sizing of the boiler and can result in a boiler that is significantly oversized when compared to the space heating demand of the home.

The average property in the England has a space heating demand of 6kW, whereas the most commonly installed gas combination boilers have a maximum space heating output over 24kW. As a result, system/heat only boilers, which are often far smaller in a heat output and yet can provide sufficient hot water with this smaller output, are often recommended for dwellings with a larger hot water demand.

Space heating demand is also calculated by considering winter temperatures, so the system can meet peak demand. But this means the system is oversized for requirements in milder temperatures in the shoulder seasons.

If a boiler is oversized, then boiler cycling is more likely to occur. Cycling is where a boiler repeatedly turns itself on and off to regulate its output to maintain the set temperature. This can cause wear and tear, reducing the lifespan of the boiler and its efficiency.

Updated Buildings Regulations in 2021 state that heating systems should not be “significantly oversized” and “when a gas combination boiler is used, the boiler type selected should be selected to modulate down to the typical heating load of the dwelling”.

Wide boiler modulation can help address the impacts of boiler oversizing. A modulation boiler can turn down its output to meet heat demand rather than needing to turn the system on and off continuously. For example, if a 30kW boiler only requires 10kW of heat, then it can modulate its output down to only use the 10kW that is required. By turning down its output, the boiler is only using the energy that is necessary to meet heating demand and is doing so without on-off cycling.

Therefore, the government is proposing that from mid-2028 all new gas combination boilers (≤45kW) placed on the GB market should be able to modulate down to at least 15% of their maximum output without on/off cycling.

Larger boilers, due to their higher levels of absolute output, may be able to modulate to lower proportions of their total output than their smaller counterparts. It is for this reason, that the government is considering an extension to the above modulation requirement for all gas combination boilers placed on the GB market, such that by 2028 all larger gas combination boilers, 45kW≥32kW, must be able to modulate their maximum output down to 10% without on/off cycling.

Oil boilers can also utilise modulation functions instead of on/off cycling. Whilst modulating oil boilers are not prevalent in the current market, newer models are being placed on the market that are capable of modulation. This now means more off-gas grid consumers can now benefit from more efficient heating systems. Given the early stages of market maturity, we are proposing that all combination oil boilers (≤45kW) be capable of modulating their heat output down to 30% of their maximum output without on/off cycling by 2028.

Gas boiler flow temperatures: Default low flow temperature factory settings

By operating at lower flow temperatures, heating systems can run more efficiently, for example, by allowing boilers to run in condensing mode. This enables the boiler to recover latent heat that would otherwise be lost thereby using less fuel to meet heat demand. Lowering the boiler’s flow temperature will improve its efficiency and ensure that it is performing to the high standard as advertised. In fact, lowering a combination boiler’s flow temperature could save a consumer over £60 a year.

Previous updates to Part L within the Building Regulations have set standards for new or replacement wet central heating systems to be designed to operate at a maximum flow temperature of 55 degrees Celsius (°C) where possible. The current standards in Approved Document L1 are for when full heating systems are replaced. We acknowledge that a flow temperature of 55 degrees Celsius (°C) would not be suitable for all households, where it is only the boiler being replaced. The government is therefore, proposing that all combination boilers should be supplied with a default low-temperature factory setting at 60 degrees Celsius (°C) by 2026. We note that for those over 65 or with pre-existing health conditions, a slightly higher flow temperature of 65°C may be more suitable to ensure homes warm more quickly.

Control classes

Superior temperature controls adjust the heating system’s flow temperature in response to the heat demand. Therefore, the capability of these controls can affect their ability to deliver most real-world cost and carbon savings. Temperature controls are used across all heating technologies such as gas and oil boilers as well as heat pumps. They are categorised into 8 different classes (Class I-VIII) depending on the various functions used:

• Class I – A room thermostat that controls the on/off operation of a heater
• Class II – A heater flow temperature control for use with modulating heaters
• Class III – A heater flow temperature control, for use with on/off output heaters, using weather compensation
• Class IV – An electronic TPI room thermostat, for use with on/off output heaters
• Class V – A load compensator, modulating the temperature and/or boiler output, maximising condensing mode
• Class VI – A heater flow temperature control including a weather compensator and room temperature sensor, for use with modulating heaters
• Class VII – A heater flow temperature control including a weather compensator and room sensor, for use with on/off output heaters
• Class VIII – Multi-sensor room temperature control, for use with modulating heaters

Each temperature control class is split up into different energy efficiency percentage uplifts that contribute to the overall space heating rating and efficiency of the heating system.

Control Class	Efficiency percentage uplift
Class I	1%
Class II	2%
Class III	1.5%
Class IV	2%
Class V	3%
Class VI	4%
Class VII	3.5%
Class VIII	5%

The government proposes to raise GB product requirements so that temperature control Classes I-III will no longer be sufficient from mid-2026 i.e. they will not be able to be placed on the market for use with boilers or any other heating system or appliance type. This will ensure that all heating system controls provide the highest possible energy efficiency benefit.

Control Classes I-III are the most basic form of boiler controls and are understood to offer the lowest benefit. Class I controls use standard on/off functionality which turn the boiler on when the temperature drops below the set temperature and turn it off when the room is at temperature. Class II and Class III controls are weather compensator controls, however, only utilise an external sensor as compared to controls in higher classes, which use a combination of external and room sensors to determine heat demand. Class II and III controls are not commonly used within the UK so removing these classes is not expected to have a significant impact.

Communication protocols

System efficiency is, in part, dependent on effective communication between the heating appliance and its controls. The strength of this communication can impact the heating system’s ability to efficiently modulate its output and lower the flow temperature, which is the key factor in determining overall system efficiency.

‘Closed protocols’ mean that only the manufacturer’s branded controls will fully function with their boilers. In contrast, ‘open protocols’ allow controls and boilers to communicate with one another, even if they are produced by different manufacturers. Open protocols enable controls to effectively adjust the boiler’s output and flow temperature. As a result of closed protocols, boilers resort to cycling their output. In practice this means the boiler will regularly turn on and off to maintain the set temperature in a property as opposed to lowering the output temperature.

‘Open protocols’ are a communication protocol which enables all relevant heating system components, including those made by different manufacturers, to be capable of communicating. This must include enabling heating controls to modulate/adjust the flow temperature of a space heater to maintain the temperature heating system rather than solely maintaining a set point temperature by switching the space heater on and off.

Within the current market, some heating systems use open protocols whereas others only use closed protocols. The most widely used open protocol, OpenTherm, is already in use by a significant portion of the boiler market and more widely so in other countries such as the Netherlands.

We understand that this can optimise the performance of both the heating system and controls, as well as adapting to a growing market of third-party control manufacturers who are independent of heating manufacturers. Allowing effective operation of heating systems by third party controls, by requiring use of open protocols, would result in greater competition, innovation and consumer choice.

The government therefore proposes to mandate that all heating controls use open protocols by mid-2026. We propose requiring oil boilers to use open protocols too but only from 2028, given the current lower levels of use of open protocols within the market for oil boilers.

We also propose to require all heating systems and temperature controls to be placed on the market with materials which explain which open protocol(s) their appliances are compatible with.

Ensuring effectiveness

Ecodesign legislation (2013/813) includes provisions designed to ensure the regulations are as effective as possible, to maximise compliance and to encourage innovation within the heating industry. Our proposals seek to ensure compliance while minimising costs faced by businesses and, ultimately, consumers.

To maximise the effectiveness of ecodesign (2013/813), we will consult on proposals:

• to update performance benchmarks for space and combination heaters, to encourage technological developments in high-performing products
• to allow boiler manufacturers to be able to self-certify their products and review compliance, through OPSS, with the boilers proposals that have been deemed acceptable for self-certification 18 months after the regulations are introduced
• to narrow product verification tolerances (from 8% to 4% for fossil fuel and electric boilers)
• to implement new standards to reduce circumvention to ensure products perform as tested

Benchmarks

There is currently a single benchmark for seasonal space heating energy efficiency of 145% (based on CC=2.5) set for all products, but this does not reflect the highest performing products currently available. Additionally, this benchmark would need to be updated to reflect our proposal to update the primary energy factor for electricity (CC) to 1.9 (as stated above). Therefore, we propose to update performance benchmarks for different types of space and combination heaters, to encourage development of high-performing products.

Type of appliance	Proposed benchmarks (Seasonal space heating energy efficiency ηs)
Oil boiler (liquid-fired boiler)	93%
Gas boiler	95%
Hybrid heat pump	165%
Ground source heat pump	229%
High-temperature heat pump	165%
Medium-temperature heat pump	234%
Low-temperature heat pump	260%

Verification tolerances

Verification tolerances are the permitted gap between the performance claimed by the manufacturer of a specific device and what can be achieved when the relevant authority tests this product. Verification tolerances were introduced to cover uncertainty that result from laboratory measurements and rounding.

At present, an 8% efficiency tolerance applies for all space heaters (including fossil fuel boilers and low carbon technologies, such as heat pumps). However, different appliances have different efficiencies – heat pumps have far greater efficiencies and far higher MEPS than boilers, and therefore a verification tolerance of 8 percentage points is a far smaller proportion of a heat pump’s efficiency than it is of a fossil fuel boiler. Additionally, fossil fuel boilers are responsible for far greater carbon emissions, therefore it is vital to ensure that these boilers are performing at, or as close as testing accuracy allows to, their advertised efficiency. Therefore, we propose limiting the verification tolerance for the seasonal space heating energy efficiency of fossil fuel and electric boilers to 4%, whilst maintaining the 8% tolerance for cogeneration heaters, heat pumps and hybrid heat pumps.

Reducing circumvention

Circumvention is the application, by manufacturers, of devices, software or other approaches which mean products can detect they are being tested and alter their performance to ensure they meet standards. The use of circumvention devices means that more carbon and other greenhouse gases could be emitted than estimated and that consumer bills could be more expensive due to greater fuel usage. Such ‘defeat devices’ have been used in other sectors, such as the automotive industry.

Given the risks posed by circumvention, we propose aligning with EU’s actions in this area which are applied to other energy-related products, such as tumble dryers, in order to prevent products from being designed to detect that they are being tested. It will prevent products from performing differently under tested condition and therefore, creating a wider discrepancy between tested and real-world performance.

Improving energy labels

It is essential that users and installers are provided with accurate information about the energy use of products on the market, to enable them to make informed decisions about what to buy.

The energy labels provided by manufacturers are a key mechanism for ensuring this. Labelling has been successful in achieving cost-effective improvements in energy efficiency and empowering consumers to purchase more efficient products.

Energy labels should present important information clearly, for use by the installer and consumer. Evidence gathered by the Department for Environment, Food and Rural Affairs (Defra) found that the usefulness of the label can be increased by improving its design, including using symbols and text to enhance familiarity and credibility.^{[footnote 4]}

The current energy labels for space heaters and combination heaters were introduced in 2013. They were updated in 2021 to replace the EU flag with the Union flag, however the other components were not reviewed at that time. Energy labels for some other energy-related products have already been reviewed and updated to ensure they include modern components such as QR codes, which enable the user to quickly access information relating to the product online.

Energy efficiency classes are intended to allow users (installers and consumers) to quickly and easily compare the energy efficiencies of different technologies and fuel types, for example fossil fuel boilers and heat pumps. Illustrating energy classes using scales and traffic light colours has been found to better enable comparison between products. The current regulation establishes a green to red scale of 10 space heating energy efficiency classes, from A+++ to G, for hydronic heating appliances (wet heating systems) with a capacity up to 70kW.

Regulation 2017/1369 establishes a requirement that the energy efficiency class scale must be rescaled if 30% of the units of models belonging to a product group sold within the market of Great Britain fall into the top energy efficiency classes (A to A+++), or 50% fall into the energy efficiency class B and above, and further technological development can be expected. The higher energy efficiency classes (A to A+++) have become overpopulated. Fossil-fuel technologies, such as gas boilers, can achieve space heating energy efficiency class A, while heat pumps are in classes A+ to A+++. The Energy-related products Policy framework^{[footnote 5]} noted that an energy efficiency scale with class A as the highest class could reduce confusion for consumers.

We will consult on proposals to:

• rescale the space heating energy efficiency classes to a 7-band A to G scale
• display the range of energy efficiency classes on visual advertising making it clear which energy efficiency scale to which this refers
• refresh the label design
• streamline the number of labels

Rescaling space heating energy efficiency classes

In accordance with regulation 2017/1369, the proposed new threshold for class A is set so that this class is vacant at the point of implementation, to encourage innovation in greater efficiency of future products.

We further propose to align the other class thresholds with current or new MEPS for different technologies, including: minimum efficiency for gas boilers (92%), our proposed minimum efficiency for hybrid heat pumps (125%), and our proposed minimum efficiency for medium-temperature heat pumps from 2029 (175%). We also propose setting one of the thresholds at 100% to clearly distinguish between non-renewable / non-cogeneration heaters and renewable and/or cogeneration heaters.

At low-temperature, we recommend that the scale should be comparable, calculated by multiplying the seasonal space heating energy efficiency thresholds proposed for medium-temperature application by 1.25.

We, therefore, propose rescaling seasonal space heating energy efficiency classes as follows:

Seasonal space heating energy efficiency class	Seasonal space heating energy efficiency ηs in %	Seasonal space heating energy efficiency ηs in %, for low-temperature application
A	ηs > 260	ηs > 325
B	200 ≤ ηs < 260	250 ≤ ηs < 325
C	175 ≤ ηs < 200	219 ≤ ηs < 250
D	125 ≤ ηs < 175	156 ≤ ηs < 219
E	100 ≤ ηs < 125	125 ≤ ηs < 156
F	92 ≤ ηs < 100	115 ≤ ηs < 125
G	ηs < 92	ηs < 115

Energy efficiency class and class range

In accordance with regulation 2017/1369, where it is not feasible to display the full energy label, customers should be provided at least with the space heating energy efficiency class, and, for combination heaters, the water heating energy efficiency class. The customer shall also be provided with the range of the energy efficiency classes so it is clear where a particular product sits in relation to the overall energy efficiency scale.

We will consult on proposals as to how this information should be displayed for different space heating products.

Full designs will be included in our consultation.

Updating label design

We will consult on proposals to refresh the label design to ensure that they clearly present useful information, including the calculated space heating efficiency of the appliance (at 1 or 2 flow temperatures, as appropriate) expressed as a percentage, symbols to indicate the fuel(s) that the appliance uses and a QR code to enable the user to find further information relating to the appliance.

Currently packages of space heating products require an additional label. To avoid unnecessary duplication, we will consult on proposals to incorporate the components in the package and cogeneration labels into the specific product labels.

Full designs will be included in our consultation.

1. Department for Business, Energy and Industrial Strategy (BEIS) (2022), ‘Improving boiler standards and efficiency’. ↩

2. BEIS (2021), ‘Boiler Plus: initial policy review’. ↩

3. BEIS (2020), ‘Energy-related products: call for evidence’. ↩

4. Department for Environment, Food and Rural Affairs (Defra) (2023), ‘The role of ecolabelling in the path to net zero: Evidence review and Theory of Change’, page 19. ↩

5. BEIS (2020), ‘Energy-related products policy framework’. ↩