James Elston
Published November 5, 2024
All modern boilers are condensing boilers, and therefore, all combi boilers are condensing boilers. However, not all condensing boilers are combi boilers.
This may sound confusing, but in this article, we will explore the key differences between combi boilers and other condensing boilers (system and regular).
We’re here to guide you through the costs and factors affecting the costs to help you determine which boiler is best for your residential or commercial needs.
Key Takeaways:
- All combi boilers are condensing boilers; however, not all condensing boilers are combi boilers.
- Combi boilers have the lowest upfront costs.
- Other condensing boilers include system and regular boilers, which are better for higher hot water demands
Contents
Condensing Boiler Vs Combi Boiler – Which Is Better?
When exploring other condensing boilers vs combi boilers, it’s important to first understand how all condensing boilers function. Each type of boiler will have its own merits, costs and disadvantages despite all being condensing models.
How do condensing boilers work?
Here is a breakdown of how all condensing boilers work:
- Fuel is burned to heat water, which flows through the primary heat exchanger. This water is used for hot water taps and central heating systems.
- When the boiler heats the water, hot gases are produced. Condensing boilers capture the heat from these gases with the secondary heat exchanger. This key component recycles heat that is lost in non-condensing boilers.
- When heat from the gases is reused, the steam cools and condenses into water vapour (condensate). This is then drained away by a specialised pipe.
It’s this condensing technology that makes these boilers that much more efficient.
Condensing boiler advantages and disadvantages
| Pros | Cons |
|---|---|
| Up to 99% energy efficient | Complex internal systems |
| Requires less fuel | More prone to a malfunction |
| Lower energy bills | High upfront costs |
| Long lifespan | Can be expensive to maintain |
| Safe and reliable | |
| Does not waste any heat from released gases | |
| Aligns with green standards |
Now that we’ve covered the basics of condensing boilers, let’s explore the various types and see how they compare.
Combi boiler
A combination boiler provides both heating and hot water on demand. These units are best suited to smaller households or flats comprised of 1-2 bedrooms and one bathroom. They are more compact than other boilers and are easily installed.
Many people opt for a condensing combi boiler as it is highly efficient, cost-effective and meets their heating needs.
Combi boilers would not work well in larger homes or where there is a high demand for hot water.
These boilers can use gas, electricity, oil or biomass as a fuel source.
What are the advantages and disadvantages of condensing combi boilers?
Apart from their convenience and compact size, combi boilers have many other advantages and drawbacks.
| Pros | Cons |
|---|---|
| Space saving | Limited hot water supply |
| Instant hot water | Reliant on mains water, therefore, must have good water pressure |
| Lower installation costs | No backup hot water |
| High energy efficiency | Not suitable for larger homes |
| Simple installation | |
| Lower energy bills |
Popular combi boiler brands/models
- Ideal Vogue Max 32
- Worcester Greenstar 8000 Combi
- Vaillant ecoFIT Pure 825C
Other condensing boiler types
The other condensing boiler types suit different needs and have different functionalities from combi boilers. System, regular and biomass boilers are suited to larger homes (4-5 bedrooms) and commercial properties.
What Are The Costs Of Condensing Boilers And Combi Boilers
The average cost of a condensing combi boiler is between £1,500 and £4,500, including installation.
The average cost of other condensing boiler types is between £1,580 and £21,000, including installation.
Condensing boiler costs
The costs below are the average cost for condensing boilers (including installation).
| Boiler type | Cost, including installation |
|---|---|
| System | £1,580 – £5,000 |
| Regular | £1,600 – £5,000 |
| Biomass | £6,000 – £21,000 |
Combi boiler costs
| Item | Cost |
|---|---|
| Unit | £500 – £300 |
| Installation | £1500 – £4,000 |
| Average Running Costs | Electric – 28p/kWh, Natural gas – 7p/ kWh |
| Average Standing Charge | 20p – 50p per day |
| Average Annual Maintenance | £90 – £100 |
As you can see, combi boilers are the more cost-effective option, especially if they are natural gas boilers. The running costs of electric combi boilers will be higher than those of other condensing boilers, but the upfront costs will be lower.
However, other factors influence the cost of condensing boilers and combi boilers.
What factors affect the costs of condensing boilers and combi boilers?
Let’s explore the factors that affect the cost of condensing and combi boilers.
Type of boiler, model and size
The type of boiler you choose (system, combi, biomass, regular) will affect your upfront costs. These boilers vary in size and installation requirements and may need additional components for functionality.
Regarding initial costs, combi boilers (specifically electric) have the lowest upfront costs. This is thanks to the simple installation process. Biomass boilers are more expensive as they have a more complex installation.
Installation
Your overall installation cost may be impacted by the following factors:
- Your location
- If you are replacing an existing boiler and the type of boiler that needs to be removed.
- Location and accessibility of the old boiler
- Property size
- Installers rates
- Additional work, labour or components
A Gas Safe registered installer must be used for your installations and removals. Eco Happy’s expert installers can help make this process easy and hassle-free.
Fuel source
The type of fuel your boiler uses will affect the upfront costs. This is because of the specific technology that is required to handle each fuel type.
Natural gas boilers tend to be more affordable than Liquefied Petroleum Gas (LPG) and biomass boilers. Electric boilers will have the lowest initial costs but this will be offset by their more expensive running costs.
Standing charge
Standing charges may vary according to your energy supplier. This a fixed daily rate and homeowners should be aware of this cost. You could end up paying anything between £110 and £182 per year for standing charges.
Maintenance
While annual servicing is a legal requirement, your boilers may also need repairs for unforeseen breaks, faults or damages. Generally, boilers with fewer components have fewer chances of needing such repairs. Combi boilers would be a good choice over a system boiler in this instance.
It would be wise to take out a comprehensive boiler cover plan in the event of breakdowns or repairs. Some policies cover annual maintenance fees as well as any ad-hoc repairs.
Which Boiler Is Best For Your Needs?
To help choose between a combi and other condensing boilers, let’s explore further factors that may influence your choice.
Price
The overall cost of your boiler needs to be considered. This is everything from the unit cost to the running costs. If you want a boiler that has low upfront and running costs, a gas combi boiler is your best option.
Installation
You can save on high installation costs by opting for an electric combi boiler, as this is the most cost-effective option. However, the running costs for this boiler will be among the highest of all the different types. This can be overcome if you choose to use solar panels with a combi boiler.
Additional components and materials may be needed for combi boilers and other condensing boilers. All condensing boilers require pipework and a flue (except electric models). This is especially important for the functioning of the flue gas recovery system.
Here’s how the addition of essential components impacts the installation costs:
- Pipework: £800- £1,000 (excluding labour)
- Flue: around £200 (excluding labour)
Installation costs also vary if the new boiler is replacing an existing one. The existing boiler would have to be removed and depending on the type, size and complexity, the labour costs for this are anywhere between £1,500 and £3,500.
Property size
Ultimately, the size of your property will be a major deciding factor in your choice of boilers. Larger homes with 2+ bedrooms and 1+ bathrooms aren’t suited to combi boilers. The best boiler for a large house is a system boiler.
Likewise, if you have high hot water requirements, a system boiler or regular boiler will be a better fit as they have a separate hot water tank. If you’re unsure about the size of your home in relation to your boiler requirements, try our Boiler Size Calculator for better insights.
Features
Apart from the obvious difference in mechanisms and components, you may want your boiler to have additional smart features. A variety of condensing boilers come readily equipped with smart technology. You also have the option of retrofitting smart thermostats.
However, these features will add to the cost of your boiler. If convenience and technological advancements interest you, check out our guide on the 6 Best Smart Boilers of 2024.
Energy efficiency
Combi boilers are the most energy-efficient, followed by system and conventional boilers respectively. However, you also need to consider the fuel source of the boiler. Generally, gas-condensing boilers are more efficient.
Additionally, a condensing boiler is much more efficient compared to a non-condensing boiler.
Safety
If we were to rank condensing boilers in order of safety from most safe to least safe, it would be:
- Combi boilers – enclosed and have fewer components.
- System boilers – a bit more of a risk because of their hot water cylinders.
- Regular boilers – the most potential risks due to their open design and numerous components.
Maintenance
Annual boiler servicing is crucial. The better care you take of your boiler, the longer it will last. Of course, things do happen and you’re likely going to experience some common boiler problems.
This is where you would need to consider which boiler type is the easiest for you to maintain.
Are some components easier to replace than others? Would emergency repairs fit into your budget?
You could also opt for a comprehensive boiler cover plan that covers repairs, replacements and annual maintenance.
Get A Quote for A Condensing Boiler Or A Combi Boiler Today
If you are interested in installing a condensing boiler, contact Eco Happy today for a free quote. Our fantastic team of boiler experts can help answer any questions you have about combi boilers, installation, and other condensing models.
FAQs
Where is the best place in the house for a combi boiler?
A condensing combi boiler is best fitted in the kitchen or bathroom. Combi boilers can be wall-mounted, either inside or outside your house. However, experts recommend installing them in the kitchen or bathroom as they’re close to your water outlets and won’t disturb other areas in your home with noise.
What is the life expectancy of a combi boiler?
Combi boilers last between 10 and 15 years. One way to ensure your boiler lasts is by keeping up with regular servicing.
How can I save even more money when it comes to boiler installation?
There are a few government grants for boiler installation. We recommend reading up to see if you qualify for these grants or schemes. These grants may cover some of your boiler costs. The currently available grants are:
- The Boiler Upgrade Scheme (BUS)
- ECO4 Scheme (Energy Company Obligation)
- The Home Upgrade Grant (HUG)
Our Verdict
If your home is smaller, we recommend a condensing combi boiler. Not only is it extremely compact, but it will also provide an efficient heating system and help lower your carbon emissions.
If you’re interested in installing a combi boiler, contact us today. Eco Happy is here to take the guesswork out of boiler installations.
James Elston
Boiler Expert
James Elston is the top boiler replacement and heating expert at Eco Happy. He has over 20 years of experience in the industry, focusing on Gas Safe boiler installations and offering home-heating and energy-saving solutions to homeowners across the UK. From sourcing the most energy-efficient combi boiler to providing specialist heating advice, James ensures that Eco Happy maintains the highest standards and best customer service.