Understanding Boiler Efficiency Ratings: What Installers Need to Know

With heightened energy costs and tightening environmental regulations in the UK, it’s important for installers to have a thorough understanding how boiler efficiency ratings work as it will help ensure optimal performance for their customers and proper regulation compliance across their business.

This guide will equip installers with all the necessary information they need around boiler efficiency ratings, to make informed decisions and deliver a superior service.

What are UK boiler efficiency ratings?

Boiler efficiency ratings define how effectively a boiler converts its fuel source, such as oil or gas, into heat. In the UK specifically, there are typically two types of efficiency ratings: the Energy-related Products (ErP) Directive and the former Seasonal Efficiency of Domestic Boilers in the UK (SEDBUK).

ErP (Energy-related Products) Directive

In 2009, the ErP directive replaced the Ecodesign Directive of the European Union, which was a framework that set mandatory ecological requirements for energy-using and energy-related products sold within the EU, including boilers.

Boilers under the ErP directive are rated and labelled on a scale which ranges from G (lowest) to A+++ (highest rating, only achievable with smart thermostats), which can help installers quickly identify the most efficient models in a brands product lineup.

SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK)

Much like the ErP, The SEDBUK rating scheme was developed by boiler manufacturers in conjunction with the UK government to create a fair comparison of the energy efficiency of boilers. Much like the ErP, it rated boilers on a scale from G to A, but it was replaced by the more comprehensive ErP in September 2015.

During its time, SEDBUK was specific to the UK rather than covering the entire EU.

What Are the Key Factors Affecting Boiler Efficiency?

Boiler efficiency can be affected by several factors, including boiler design, fuel types and proper installation.

Boiler Design

As the boiler’s efficiency rating is determined by how well it can convert fuel into heat, the design of the boiler is a major factor. For instance, condensing boilers are remarkably efficient due to the way they capture and reuse heat from flu gases, which would otherwise be wasted.

Fuel Types

The type of fuel used in a boiler can also affect its efficiency rating. While some properties will still need traditional fuel types such as oil, they are slowly being phased out in new-build properties across the UK and abroad, making way for more efficient fuel types like natural gas that do not require the same infrastructure that oil does and do not emit the same level of carbon.

Correct Installation

Ensuring the boiler is installed properly is crucial to overall boiler health and efficiency. Whether it’s including proper venting, insulation or connecting the boiler to devices such as smart thermostats, the efficiency of a boiler starts at its installation.

Before installation, the correct size boiler must be chosen to maximise efficiency. A boiler that is too small or not powerful enough will struggle to adequately heat the property, while an oversized one could lead to excessive energy use and higher bills.

Why High Efficiency Boilers Matter in the UK

High efficiency boilers have an important part to play in the UK, bringing benefits to property owners and installers alike.

Lower Bills and Less Callouts

Installing high efficiency boilers in your customers homes means lower energy bills for them, and lower customer dissatisfaction as the boiler will be running at a healthy rate without having to work harder due to sub-optimal fuel efficiency.

Environmental Consciousness

With environmentally focused initiatives such as the UK government’s commitment to achieving net-zero emissions by 2050 becoming more and more commonplace, offering high-efficiency boilers to your customers can help you to become an important part of the solution.

By reducing fuel consumption, or even by simply optimising the way that fuel is used, these boilers help lower carbon emissions and contribute to a cleaner and safer future.

Regulatory Requirements

UK building regulations ensure that boilers are safe and energy efficient. Approved Document J, which applies when changing an existing hot-water central-heating boiler to another form of heating system, states that each boiler must have a minimum efficiency of 86% for gas and 85% for oil.

When it comes to condensing boilers, they must have a ErP rating of A or B unless an assessment by a Gas Safe Register installer suggests that it is not viable to install one, then a boiler rated C or D can be installed as long as they have the minimum fuel efficiencies previously mentioned.

Future-Focused High-Efficiency Boilers

Understanding boiler efficiency ratings is of the utmost importance for installers. By staying informed about the latest regulations and technological advancements, installers can ensure they provide the best possible service to their customers.

Recommending high-efficiency boilers not only saves energy and reduces costs for property owners but can also help installers play a crucial part in building a more sustainable future for us all.

Are you interested in staying up to date with advancements in boiler technology? Keep an eye out on our blog, or get in touch for more information on how we’re improving boiler fuel efficiencies across the UK.