How Efficient is Your Current Boiler?
With rising energy prices and colder winters, one of the biggest questions homeowners are asking is: how efficient is your current boiler? Your boiler is often the single largest consumer of energy in your home, accounting for more than half of your household’s energy use. If it’s not running efficiently, you could be losing hundreds of pounds each year without even realising it.
An inefficient boiler doesn’t just cost more money — it can also reduce comfort levels in your home, take longer to heat your water, and increase the risk of unexpected breakdowns. In some cases, older boilers may even produce higher carbon emissions, meaning you’re paying more while having a greater environmental impact.
At Brightside Heating, we believe knowledge is the first step toward savings. By understanding how your current boiler performs, you can make smarter decisions about whether to repair, upgrade, or replace it with a modern, high-efficiency model. Our goal is simple: to help you stay warm, cut energy bills, and make sure your heating system works reliably when you need it most.
Ways to Check Your Boiler’s Efficiency
There are a few key ways to find out your boiler’s efficiency:
- Check the ErP Rating: Since 2015, all new boilers have an energy label, similar to those on fridges and washing machines. This label gives the boiler an ErP (Energy-related Products) rating, a simple A-G grade. An A-rated boiler is highly efficient (90%+), while a G-rated boiler is very inefficient.
- SEDBUK Rating: For older boilers, you might find a SEDBUK (Seasonal Efficiency of a Domestic Boiler in the UK) rating on a sticker on the boiler itself or in the manual. This is a percentage figure that tells you how efficient the boiler is. If you can’t find it, you can look up your boiler model on the SEDBUK website.
- The Age of Your Boiler: As a general rule, the older your boiler, the less efficient it is likely to be. If your boiler is over 10 years old and isn’t a modern condensing model, it’s likely operating at a much lower efficiency.
How Efficient is a 15-Year-Old Boiler?
This is a common question, and the answer is usually not very efficient at all. A 15-year-old boiler is most likely a non-condensing model. These boilers typically have a SEDBUK efficiency rating of around 60-70%. This means that for every pound you spend on heating your home, 30p to 40p is being wasted, literally going up the flue as heat.
Compare this to a new A-rated condensing boiler, which is over 90% efficient. Replacing a 15-year-old boiler with a new, modern one could reduce your heating bills by hundreds of pounds per year. It’s not just a matter of performance; it’s a matter of financial sense in the long run.
How Efficient Are Boilers in the UK?
The average efficiency of boilers in the UK has been steadily increasing, but there are still millions of older, inefficient boilers in homes across the country. According to a report by the Energy Saving Trust, the average UK household could save a significant amount on its energy bills by upgrading an old, inefficient boiler to a new, modern one.
The push towards higher efficiency is driven by new regulations that have made it mandatory for all new gas and oil boilers to be condensing models since 2005. This is why if your boiler is older than that, it’s very likely to be a non-condensing, inefficient model.
If you’ve discovered your boiler is a low-efficiency model, it might be time to consider a new installation. While the upfront cost of a new boiler can seem high, the long-term savings on your energy bills, combined with fewer breakdowns and a longer warranty, often make it a wise investment. At Brightside Heating, we can help you assess your current boiler’s efficiency and provide a free, no-obligation quote for a new, highly efficient model. You can find more information on our Boiler Repairs and Installations page.