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Combi Boiler Installation Guide and Prices 2024
- A new combi boiler installation ensures energy efficiency, cost savings, space-saving design, and on-demand hot water. Also, high efficiency, modern combi boilers produce fewer carbon emissions, reducing your household's carbon footprint.
- Replacing an existing combi boiler can take 1 to 2 days, and converting from a regular boiler to a combi boiler usually takes around 2 days.
- The average cost for installing a new combi boiler is around £2,500. Replacing an old combi boiler with a new one can cost between £500 and £1,500. Converting from a different type of boiler can cost from £1,500 to £4,500.
Combi boilers dominate the UK market for a reason. Their high efficiency (92% and above) translates to lower energy bills and a gentler environmental impact. And a new combi boiler installation could save you up to £430 annually!
This article explores the factors affecting combi boiler installation costs, including boiler type and home size. And for a precise new boiler cost tailored to your home, consider getting quotes from qualified engineers. However, finding a trustworthy expert can stretch for days if done alone.
Thankfully, GreenMatch can connect you with up to 3 vetted professionals for a hassle-free comparison and installation process. Our service is completely free and it only takes 30 seconds to get started.
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Combi boiler installation: How does it work?
A combi boiler installation could take anywhere from 6 hours up to 3 days. More complicated installations will take the longest.
These might involve having a combi boiler fitted in a new location in the home or switching from a system or regular boiler type. The process can also be complicated if the boiler is located in a difficult-to-access area, such as a loft or a small cupboard.
Combi boiler installation diagram
How do you install a new combi boiler? Below, we’ve outlined everything involved in a simple combi boiler installation.
- Old boiler removal: The old boiler is disconnected from the gas supply and removed alongside any fixtures holding the boiler in place. An existing hot water cylinder or cold water tank may also need to be removed.
- System flush: Chemicals are left in the heating system to break down any debris which can then be flushed out. Your installer might also recommend a power flush depending on the amount of debris build-up.
- Laying new pipework: The combi boiler must be installed with gas pipework that is at least 22mm in diameter to withstand high volumes of gas on demand. Therefore, 15mm pipes will need to be upgraded.
- Fitting the new boiler: Installing in a new location will require additional parts and labour costs. Fitting your new boiler is straightforward as long as the installer can easily access the area.
- Additional upgrades: There are several options to help maintain your new boiler. These include a magnetic filter to prevent debris build-up, a new boiler flue, and heating controls.
- Registering your new boiler: Your new boiler will need to be registered with the manufacturer to ensure your warranty is valid.
How long does it take to fit a boiler?
Fitting a new boiler (connecting the boiler to the existing pipework and system) takes anywhere between 6 hours and 3 days. However, the total time frame can vary depending on several factors.
A straightforward like-for-like combi boiler replacement in the same location typically takes 4-6 hours. This involves replacing the existing boiler without extensive adjustments.
However, if you are installing a new type of boiler, the timeframe may extend up to 3 days or more. This is because removing the old boiler and adjustments to pipework are necessary. Also, additional tasks may include adding or removing the external cold water tank or hot water cylinder.
It's crucial to note that relocating the boiler can significantly impact both time and cost. If, for instance, the installation site is difficult to access, the process might exceed the 3-day timeframe.
Installation cost of a combi boiler
Fitting a combi boiler typically costs between £1,500 and £2,500. More complex installations usually involve switching to a new boiler type or moving the boiler to a new location in the home.
For these types of replacements, the pipework will need to be adjusted, and additional units will need to be removed. Therefore, they could cost £4,000 and beyond.
Combi to combi boiler replacement costs
This type of like-for-like swap will likely cost an average of £1,100–£3,500, comparatively less than other boiler replacements.
The combi boiler replacement process is relatively straightforward and typically takes about 1-2 days, as it does not involve significant changes to the existing infrastructure.
| Combi-combi boiler replacement | Average price range |
|---|---|
| New combi boiler | £500-£2,000 |
| Installation costs | £600-£1,500 |
System to combi installation costs
Replacing a system boiler with a combi takes additional time and labour to adjust the pipework and remove the hot water cylinder.
On average, this will cost around £1,500–£5,600 and requires 2-3 days of work.
| System-combi boiler replacement | Average price range |
|---|---|
| New combi boiler | £500-£3,000 |
| Installation costs | £1,000-£2,600 |
Conventional to combi installation costs
A conventional-to-combi boiler replacement takes the most time since the hot water cylinder and additional cold water tank must also be removed. Together, these costs will reach around £4,500 to have a combi boiler fitted.
Given the higher price range for this type of boiler replacement, it might serve you well to instead consider a new conventional boiler to keep installation costs down.
| Conventional-combi boiler replacement | Average price range |
|---|---|
| New combi boiler | £600-£3,500 |
| Installation costs | £1,000-£3,500 |
These numbers are just estimates and can differ from your home's final combi boiler installation price. Consult an experienced local boiler engineer to get the most tailored advice.
You can search for installers and collect the information yourself, but how time-consuming and stressful would that be? Would you know if the installer you spent hours looking for was certified and had all the necessary expertise?
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Why should you install a combi boiler?
Combi boiler installation can offer numerous benefits, including high efficiency, space savings, and instant hot water. Let's break down some of the most crucial benefits.
Benefits and advantages of a combi boiler
Combi boilers have become a popular choice for many homeowners due to their numerous benefits:
- High efficiency: Combi boilers have an efficiency rating of 90-94%, making them more energy-efficient than conventional boilers. This can lead to significant savings on energy bills.
- Compact size: These boilers don't require separate hot water cylinders or cold water storage tanks, making them ideal for smaller homes or properties with limited space. They can often be installed in kitchen cupboards or other small spaces.
- Instant hot water: Combi boilers provide hot water on demand directly from the mains, eliminating the need for a hot water storage tank. This means you get instant hot water whenever you need it.
- Easy installation: Combi boiler installation is generally easier and quicker, with fewer components required compared to conventional systems.
- Cost-effective: Due to their efficiency and the reduced need for additional components, combi boilers can be more cost-effective both in terms of installation and ongoing maintenance.
- Space-saving: The absence of bulky water tanks frees up space in your home, which can be used for other purposes.
Things to consider when installing a combi boiler
Before installing a new boiler of this type, there are several factors to consider to ensure it meets your needs:
- Mains water pressure: Combi boilers rely on good mains water pressure to function effectively. If your home has low mains pressure, this could affect the performance of the boiler.
- Property size and hot water demand: Combi boilers are generally more suitable for smaller homes with lower hot water demand. Larger homes with multiple bathrooms may require a system that can handle higher demand.
- Installation location: Consider where the boiler will be installed. It should be placed in a location that allows for adequate ventilation and easy access for maintenance.
- Boiler size and output: Ensure the boiler's output is sufficient to meet your household's heating and hot water needs. A heating engineer can help determine the appropriate size and output for your home.
- Safety and compliance: Installation must be carried out by a Gas Safe registered engineer to comply with building and safety regulations.
When should you get a new combi boiler installed?
There are several indicators that it might be time to replace your existing boiler:
- Age: Boilers typically last between 10 and 15 years. If your boiler is approaching this age, it may be time to consider a replacement.
- Frequent breakdowns: If your boiler requires frequent repairs or has recurring issues, it may be more cost-effective to replace it rather than continue with repairs.
- Rising energy bills: Older boilers are often less efficient. If you notice a significant increase in your energy bills without a corresponding increase in usage, it could be a sign that your boiler is no longer operating efficiently.
- Inconsistent heating: If your radiators take a long time to heat up or you experience inconsistent hot water supply, it may indicate that your boiler is struggling to meet your home's demands.
- Unusual noises or smells: Strange noises or smells coming from your boiler can indicate serious issues that may require replacement.
Make sure your boiler gets regular maintenance and timely replacements so that your heating system remains efficient and reliable.
Find a combi boiler installer
Every home has unique specifications that help decide the final new combi boiler and installation costs. Therefore, consulting a professional combi boiler installer is the best way to learn the true costs, how long the job will take, and any additional components to consider.
Comparing quotes from multiple installers is a cost-effective way to find the best combi boiler deals and the cheapest rates. However, such research can take days or weeks if done alone.
GreenMatch can eliminate this extra effort by directly connecting you with up to 3 heating engineers from our network of trusted installers. All of our installers are Gas Safe or OFTEC registered. Simply click the button below to be taken to our 30-second form.
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