The Complete Guide to Boiler Efficiency: How to Cut Energy Bills and Stay Warm
Your Boiler
Your boiler is one of the hardest-working systems in your home, providing warmth and hot water every day. But over time, even a reliable boiler can lose efficiency — leading to higher energy bills, uneven heating, and unnecessary wear.
In this guide, the experts at P A Henery Ltd explain what boiler efficiency really means, what affects it, and how regular servicing can keep your system performing at its best.
What Is Boiler Efficiency?
Boiler efficiency measures how effectively your boiler converts fuel into usable heat. A modern A-rated condensing boiler can achieve over 90% efficiency, meaning very little energy is wasted. Older, non-condensing models can drop as low as 60–70% — so you lose a large portion of your heating cost straight up the flue.
What Affects Your Boiler’s Efficiency?
- Age of the boiler: older systems naturally lose performance as components wear.
- Maintenance history: a neglected boiler can quickly develop blockages or faulty parts.
- Water quality: sludge or limescale restricts flow and reduces heat transfer.
- Thermostat & controls: outdated settings waste energy and fuel.
- Installation quality: poor installation can undermine even a brand-new system.
Simple Ways to Improve Boiler Efficiency
1. Book an annual boiler service
A professional service ensures your boiler is cleaned, tested, and adjusted for maximum performance.
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2. Bleed your radiators regularly
Removing trapped air improves circulation and helps your system heat up evenly.
3. Install a smart thermostat
Smart controls reduce wasted energy and learn your heating habits for more efficient operation.
4. Powerflush your system
If your radiators have cold spots or your boiler is noisy, a powerflush removes sludge and debris, restoring efficiency.
5. Upgrade to a modern condensing boiler
If your boiler is over 10–15 years old, replacing it can dramatically reduce your bills and carbon footprint.
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How Regular Servicing Saves You Money
Think of servicing like a health check for your boiler. During a service, an engineer will inspect critical components, clean filters and burners, and check gas pressure and emissions. This not only keeps your system safe — it helps catch small issues before they become expensive breakdowns.
Did you know?
An efficient, well-maintained boiler can save you up to 15% on your annual heating costs.
When to Replace Your Boiler
- It’s over 15 years old
- You experience frequent faults or uneven heating
- Spare parts are difficult or expensive to source
- It has an efficiency rating below 80%
Upgrading to a new, A-rated boiler is an investment that pays for itself through energy savings and reliability.
Key Takeaways
- Annual servicing keeps your boiler safe, efficient, and long-lasting.
- Powerflushing and clean heating water dramatically improve performance.
- Smart thermostats and modern controls reduce wasted energy.
- Replacing an old boiler can save energy and improve comfort.
Need Expert Help?
The qualified engineers at P A Henery Ltd provide professional boiler servicing, powerflushing, and heating maintenance across South Croydon and surrounding areas.
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Our team will be happy to book in your next inspection.