Converting your traditional boiler to a modern, efficient combi boiler is becoming a popular choice among homeowners looking to reduce energy bills and save space. But before making the switch, there are several important factors to consider, including the cost of installation, the benefits of a combi boiler, and whether it’s the right choice for your home. This guide will walk you through all the key aspects of transitioning from a conventional boiler to a combi boiler and what you can expect in terms of costs and considerations.
Why Switch to a Combi Boiler?
One of the main reasons for replacing an older boiler system with a combi boiler is energy efficiency. Unlike traditional boilers that rely on stored hot water, combi boilers heat water directly from the mains, reducing energy consumption and cutting costs on your utility bills. With rising energy prices, upgrading to a combi boiler can save you a significant amount of money over time.
Other key reasons to consider making the switch include:
- Space-saving design: Combi boilers are compact and eliminate the need for a separate hot water tank or header tank.
- Simplified installation: A combi boiler combines both heating and hot water into one unit, reducing the complexity of the system.
- Hot water on demand: You won’t have to wait for a water tank to heat up, as combi boilers provide instant hot water whenever you need it.
What is a Combi Boiler?
A combi boiler (short for combination boiler) is a modern heating system that provides both heating and hot water from a single, compact unit. Unlike traditional systems that rely on separate components like immersion heaters or hot water tanks, combi boilers use mains pressure water and heat it on demand. This makes them ideal for smaller homes or apartments where space is at a premium.
Combi boilers are highly efficient, with many models offering efficiency ratings of 90% or higher. This is a significant improvement compared to older boilers, which often waste a large amount of energy heating stored water that may not be used.
Read about: Types of Boilers Explained: Combi, System, and Heat-Only
Benefits of Combi Boilers
Switching to a combi boiler offers several advantages over traditional boiler systems:
- Energy Efficiency: Combi boilers are known for their high efficiency, helping homeowners save on energy costs. By heating water directly from the mains as needed, they avoid the energy waste associated with heating and storing water in a tank. According to the Energy Saving Trust, upgrading to a modern combi boiler could save you around £340 annually on energy bills while reducing carbon emissions by up to 1,500 kg each year.
- Compact Design: These boilers are perfect for smaller homes or properties where space is a concern. With no need for additional tanks or cylinders, combi boilers can fit into tight spaces like kitchen cupboards.
- Instant Hot Water: One of the biggest advantages of a combi boiler is the ability to provide hot water on demand. You’ll never have to worry about running out of hot water or waiting for a tank to refill and heat up.
- Simpler Installation: Since a combi boiler combines heating and hot water in one unit, the installation process is simpler compared to other systems. This not only reduces labor time but also lowers the overall cost of installation.
- Flexible Placement: Thanks to their compact size, combi boilers can be installed in a variety of locations within your home. This flexibility can be especially useful if space is limited.
Read about: top Combi Boilers & brands in UK
Considerations Before Making the Switch
While combi boilers offer many advantages, they may not be suitable for every home. Before making the switch, it’s important to consider a few factors:
- Hot Water Demand: If you live in a large home with multiple bathrooms or a high demand for hot water, a combi boiler may struggle to keep up. In such cases, you might need to consider a storage combi boiler or a system boiler, which comes with a built-in water tank for additional hot water storage.
- Water Pressure: Combi boilers rely on good mains pressure to supply hot water. If your home has low water pressure, the performance of a combi boiler may be compromised.
- Initial Costs: The upfront cost of converting from a conventional boiler to a combi boiler can be higher than a standard replacement. However, the long-term energy savings can offset the initial investment.
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The Process of Changing to a Combi Boiler
Converting from a traditional boiler system to a combi boiler involves several steps. Understanding the process can help you better prepare for the installation and any potential disruptions.
- Draining the Central Heating System: Before the old boiler is removed, the entire heating system (including radiators) will need to be drained.
- Removing the Old Boiler and Tanks: If your current system uses a hot water cylinder and header tank (typically located in the attic), these will need to be removed.
- Upgrading Pipework: Most conversions require upgrading the gas pipework to accommodate the new combi boiler, usually to a 22 mm pipe for proper gas flow.
- Installing the New Combi Boiler: The new combi boiler will be installed, often in a more flexible location since it doesn’t require additional tanks.
- Flushing the System: A chemical or power flush may be performed to clean out any sludge or debris in the existing heating system, ensuring optimal performance of the new boiler.
- Installing Smart Thermostats: Many modern boilers come equipped with smart thermostats like Nest or Hive, allowing you to control your heating system more efficiently.
- Safety Checks and Certification: Once the installation is complete, your Gas Safe engineer will perform safety checks, register the warranty, and provide building regulation certification.
Read more: Step-by-Step Guide to Boiler Installation | Expert Tips
How Long Does It Take?
On average, converting from a conventional boiler to a combi boiler takes about two days. This is longer than a like-for-like boiler replacement, which typically takes just one day. The additional time is due to the complexity of the conversion process, including the removal of old components and the installation of new pipework.
Costs of Converting to a Combi Boiler
Converting to a combi boiler is more expensive than a standard boiler replacement due to the additional labor and components involved. The cost for a typical conversion ranges from £2,500 to £4,500, depending on the complexity of the job, the size of the property, and the specific model of the combi boiler.
Example Costs for Combi Boiler Conversions:
| Boiler Model | Approximate Cost |
|---|---|
| Ideal Logic 24kW | From £2,790 |
| Viessmann Vitodens 050-W 29kW | From £3,039 |
| Ideal Logic 30kW | From £2,990 |
| Viessmann Vitodens 100-W 26kW | From £3,370 |
Back Boiler to Combi Conversion Costs
If you’re converting from an older back boiler system (typically located behind a fireplace) to a combi boiler, the costs can range from £3,000 to £5,000. Back boiler conversions tend to be more expensive due to the awkward location and additional labor required to remove the old system.
Final Thoughts: Is It Worth It?
Switching to a combi boiler can be a smart investment, especially if you’re looking to improve energy efficiency, save space, and reduce your heating bills. While the upfront costs can be higher than a standard boiler replacement, the long-term savings and convenience of a combi boiler make it an attractive option for many homeowners.
When considering a boiler conversion, always consult with a Gas Safe registered engineer to assess whether a combi boiler is the right choice for your home. And remember, the most reliable brands often come with extended warranties, giving you peace of mind for years to come.
Read about: How Long Does It Take to Fit a New Boiler?
For a fixed-price quote and next-day installation options, get in touch with our team today. We offer flexible payment plans, including 0% interest financing, and can provide a 12-year guarantee on select boiler models.
