What Is An ERP Rating & Why Boiler Efficiency Is Important

You may have seen your electrical appliances having a sticker with the term ‘ERP’ on it. Have you ever wondered what does the term means? The energy rating is crucial when purchasing a new boiler. Why the efficiency rating or ERP rating so important for new boilers?

In this guide, we’ll walk you through everything you need to know about ERP rating and energy-efficient boilers. Let’s get started!

What Is Boiler Efficiency?

The manufacturers calculate boiler efficiency by assessing the fuel it converts into usable energy. It also takes into account the amount of fuel the boil wastes throughout the process. Depending on the energy-efficiency percentage, the boiler will receive an alphabetical rating.

What Is ERP?

The ERP stands for Energy Related Products Directive. ERP is the European legislation that dates back to 2009. The ERP applies to all electrical appliances and even modern boilers that consume energy to work.

This directive includes both commercial and domestic heating products such as water heaters and boilers. The ERP aims to encourage all manufacturers to take up the energy-efficient route. The manufacturers have an obligation to be kinder to the environment.


SEDBUK stands for ‘Seasonal Efficiency of a Domestic Boiler in the UK.’ It was the UK government that developed this energy-efficient practice. SEDBUK refers to the annual efficiency achieved by domestic appliances. To calculate the SEDBUK rating, testers consider the fuel type, UK climate change, ignition type, and boiler water content.

Why an Energy Efficient Boiler Is Essential

Here’s why it is essential to have an energy-efficient boiler:

  • You could save money on heating and energy bills with more boiler efficiency.
  • It can help you bring down gas emissions.
  • Boiler efficiency is also essential for stabilizing climate change.

How Efficient Is Your Boiler?

If you want to figure out your boiler’s efficiency, you can check out the little sticker on the unit. If the number on the sticker has worn out, you can even lookup the model number on the internet. Another way to identify the boiler efficiency is by looking up the brand name under the pipes. Once you find the brand name, you can refer to the PCDB database.

How to Improve Your Boiler Efficiency

Here are some excellent ways to make sure that your boilers are energy saving:

Annual Boiler Service

An annual boiler service will ensure that your new boiler operates as efficiently as possible. It can also help you prevent fuel wastage. Besides, you’ll be able to save up on heating bills. Most importantly, you’ll be taking an active step towards reducing the carbon footprint.

Bleed the Radiators

When the users bleed the boiler’s radiators, it releases the air that the boiler trapped inside. This whole process significantly improves the efficiency of your boiler system. It also means a warmer home and much cheaper energy bills.

If you don’t know to bleed the radiators, you can check out video tutorials or take the help of heating engineers.

Check Water Pressure

If the boiler is operating at low pressure, it might be more energy efficient. Besides, low pressure can also improve the steam quality. Many professionals recommend running your boiler at low water pressure for this reason.

Insulate Your Water Cylinder & Pipes

When you insulate your water cylinder and pipes, the boiler will stay much warmer. How will this improve the efficiency ratings for your boiler? Well, your boiler won’t have to use up extra fuel to heat itself. It could generate more heat when the water channels have insulation.

Use a Smart Thermostat

A smart thermostat will only turn on the boiler when the weather demands it. The thermostat will detect when the temperature is too cold and only then turn on the boiler. This process will help your boiler achieve more energy efficiency and save plenty on energy bills.

Replace your Boiler

If your boiler is above 25 years old or is broken, perhaps it’s time for a change. The best decision at this point is to invest in new boilers. These new boilers will follow ERP directives and help you save more money on heating bills.

Last Updated on April 11, 2021

Frequently Asked Questions

What Does ERP Compliance Mean?

ERP compliance indicates that the electrical products need to follow energy-efficient standards. It also means that all energy-related products must reduce harmful gas emissions.

How Efficient is a 20-year-old Boiler?

The energy efficiency of a 20-year old boiler is about 75%. However, there are multiple ways by which you can enhance it.

Which Boiler is More Efficient?

A boiler that has at least 92% ERP has the best efficiency. Besides, the boiler must have a low minimum output to be more efficient. If the electrical boiler has an ‘A’ rating, it is efficient and meets good standards.

David Thompson

Author: David Thompson

Dave has been involved in the UK building sector for over 3 decades and has developed a particular interest in energy efficiency in the home.

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