How Much Does It Cost to Have a Combi Boiler Installed?
How Much Does It Cost to Have a Combi Boiler Installed?
Now, here’s a question we hear all the time…
How much does it cost to have a combi boiler installed?
In this blog, we’ll cover:
✅ What’s involved in installing a new Combi boiler
✅ What happens when you’re converting to a Combi boiler
✅ The best location for installation
✅ The costs of both types of jobs and what you can expect to pay
✅ The benefits of a Combi boiler
✅ And, of course, the downsides you should be aware of
Let’s dive in!
The Evolution of the Combi Boiler
Many years ago, the Combi boiler simply didn’t exist. However, as with all technology, our needs evolved, and so did the solutions available to us. The idea of a single unit that could handle everything—both heating and hot water—became incredibly appealing.
In the past, homes used separate appliances like geysers, Ascot heaters, and large floor-standing conventional boilers. The technology to provide hot water and heating existed, but in separate units. Eventually, someone saw the potential to combine these functions into one compact system. And just like that, the Combi boiler was born!
As the name suggests, a combination boiler merges two functions into a single unit: heating and hot water. This innovation has transformed the way we heat our homes, making the process more efficient and space-saving.
The Two Types of Advice in Our Industry
When seeking advice about boilers, you’ll come across two types of people:
Tellers – These are the ones who provide you with straightforward information, no strings attached.
Sellers – These folks are more focused on making a sale than giving you the full picture.
When you get quotes for a new boiler installation, you’ll receive a mix of opinions, facts, potential obstacles, and, most importantly, information on the level of disruption the work will cause in your home—both short-term and long-term.
As with any new technology, there’s always a learning curve. But let’s not get ahead of ourselves! We’ll break everything down for you in the right order.
So, let’s start with the installation process.
What’s Involved in Installing a New Combi Boiler?
If you currently have a hot water cylinder and want to remove it, you might be considering this upgrade to free up space—perhaps for a loft conversion or extra storage. Let’s face it, we all love more storage!
Another big reason people opt for a Combi boiler is the appeal of instant hot water on demand. With our modern, fast-paced lifestyles and unpredictable schedules, having a system that works efficiently whenever we need it is a game changer.
Choosing the Right Location
At this stage, the most crucial thing to consider is the placement of your new boiler. Since your Combi boiler will be producing all your hot water, it’s important to think about how far the hot water needs to travel to reach your taps.
For example, if you live in a three-story townhouse and place the boiler in the loft, but your kitchen is on the ground floor, that’s a long way for hot water to travel. This could result in frustratingly long wait times and wasted water.
However, if your Combi boiler is installed in the right location—after thorough checks and planning—it can be a fantastic addition to your home.
Additionally, modern higher-output Combi boilers can now provide unvented pressures and strong water flow, as long as only one appliance is in use at a time. Helping you understand Just How Much Does It Cost to Have a Combi Boiler Installed?
Things to Consider Before Switching to a Combi Boiler
A Combi boiler relies heavily on good mains water pressure. Without a strong water supply, the boiler won’t function efficiently. This is why we highly recommend having a professional check your home’s water pressure before switching to a Combi system.
How Much Does a Combi Boiler Installation Cost?
If you’re converting from a traditional tank-fed system to a Combi boiler, you can expect to pay anywhere from £3,000 to £5,000. However, as with anything, there are plenty of variables that could affect this cost, such as:
Flue positioning
Gas supply upgrades
Boiler output size
Brand of boiler
Power flushing and pipework adjustments
For the most accurate quote, we strongly advise booking a visit from a qualified heating professional. They can assess your home and provide a detailed, itemised estimate, ensuring you understand what to expect during installation.
Replacing a Combi Boiler
If you already have a Combi boiler and need to replace it, the process is much simpler. In most cases, you just need to swap it out for a similar model.
Finding the Right Replacement
To find a suitable replacement, first, determine your current boiler’s output. You can usually find this information on the boiler itself—it’s displayed on the specification label.
For example, if you have an Alpha 28C, this means your boiler’s output is likely 28kW. Most Combi boilers have a heating output of around 24kW, which is sufficient for many UK homes. However, the hot water output (reflected in the boiler name) is what varies between models.
If you’re happy with your current shower pressure and hot water performance, you can opt for a boiler with a similar output. But if you’re looking to improve your shower experience or speed up how quickly your bath fills, we’d recommend having a professional test your flow rates and water pressure. This will help determine whether a higher-output Combi boiler is right for you.
How Much Does a Combi Boiler Replacement Cost?
The cost of replacing a Combi boiler typically starts at around £2,000, but depending on your specific needs, it can go up to £4,500.
The Pros and Cons of a Combi Boiler
What’s Great About a Combi Boiler?
✅ Hot water on demand (not instant, but very fast!)
✅ High-pressure water flow for great showers
✅ Space-saving—removing tanks frees up room for storage or home improvements
✅ Energy-efficient—less heat loss compared to traditional systems
What’s Not So Great?
⚠️ Water waste—if the boiler is installed too far from taps, you may waste water waiting for it to heat up
⚠️ Limited multi-tap operation—water flow decreases if multiple taps are used at the same time
⚠️ Larger gas supply needed—switching from a heat-only system may require upgrading your gas supply, adding to installation complexity
⚠️ Disruption during installation—removing old tanks and rerouting pipework can be invasive, depending on your home’s layout
What Would Plumble Recommend?
Here at Plumble, we’re big fans of Worcester Bosch boilers. They offer a wide range of options, from low-output models to powerful high-output boilers.
With their award-winning reliability and excellent customer service, we believe most homeowners can find a Worcester Bosch boiler to fit their budget.
Check out their boilers here!
We hope you found this blog helpful! If you have any questions, thoughts, or requests for future topics, let us know in the comments—we’d love to hear from you!
Thanks for reading, and have a great day! 😊
