Are you looking for a new system boiler and wondering how much it may cost? In this guide we explore the average prices in the UK, as well as top tips on securing the best quote.
The key thing to remember is that the cost of a standalone system boiler is not the only cost you will need to consider, the Gas Safe installation i.e. labour costs are also a major factor.
It’s also important to consider the complexity of the install e.g. do you want to move your boilers location?
Below we cover standalone system boiler prices, along with some of the most common installation scenarios.
System Boiler Costs Key Takeaways:
- The average cost of a system boiler ranges from £600 – £2,500 and for system boiler installation they range from £1,500 to £3,500.
- Factors that impact the price include the brand, warranty length, installation complexity and any extras.
- To get an accurate quote for a new system boiler, you can start your application with Which? approved boiler installers here.
How much does a system boiler cost?
For the system boiler itself, the price you will pay largely depends on the brand you choose, as well as the power output i.e. boiler size and the warranty period included.
System boilers start from as little as £500, but please bear in mind that you will typically be foregoing the more generous warranty period, often found with higher priced models.
| BRAND & MODEL | SIZE/OUTPUT | WARRANTY | PRICE |
|---|---|---|---|
| Biasi Advance Plus System | 16kW | 5 years | £500 |
| Vokera Vision S System | 20kW | 7 years | £706 |
| Ideal Logic+ System | 15kW | 7 years | £800 |
| Glow-worm Energy System | 25kW | 7 years | £830 |
| Baxi 600 System | 18kW | 7 years | £960 |
| Viessmann Vitodens 100-W System | 30kW | 5 years | £1,100 |
| Vaillant ecoFIT Pure System | 25kW | 2 years | £1,100 |
| Worcester Bosch Greenstar 4000 System | 24kW | 5 years | £1,120 |
How much does it cost to have a system boiler installed?
Installing a new system boiler will cost between £500 and £1,000 on average, depending on the complexity of the installation.
For example, a like for like swap e.g. replacing your current system boiler in the same location is going to be cheaper than replacing your system boiler, together with the tank in a new location.
So to conclude, the average cost of a complete system boiler install – that includes the boiler, a cylinder, a system clean and labour, can range from £1,500 to £7,000 (excluding VAT).
What size system boiler do you need for your home?
The size of the system boiler e.g. it’s power output (measured in kilowatts) is another important consideration.
Typically, the more heat and hot water needed for the property and household requirements, the higher the kilowatt output, or boiler size will need to be.
The table below provides an estimate of the system boiler size you will require based on the number of bathrooms and radiators you have in your property:
| BEDROOMS | RADIATORS | BATHROOMS | RECOMMENDED SIZE |
|---|---|---|---|
| 1-2 | Up to 10 | 1 | 9kW – 18kW |
| 3-4 | 10+ | 2-3 | 18kW – 26kW |
| 5+ | 20+ | 4+ | 27kW – 40kW |
Please bear in mind that the above table provides an estimation only and you will need to seek professional assistance to know exactly what size boiler your home requires.
System Boiler Prices FAQ
What is a System Boiler?
System boilers are quite similar to conventional boilers in that they both supply hot water to the central heating system and store it in an unvented hot water cylinder.
They do, however, differ in that they do not need as much storage space because their water is supplied straight from the mains’ water supply.
They also deliver water under high pressure, resulting in a more constant flow rate.
A system boiler comes with most of the components needed to provide heating and hot water.
An unvented cylinder that contains hot water is the sole component that is required outside.
System boilers do not require a water tank in the loft because they get their water straight from the mains water supply (unlike a regular (heat-only boiler).
They then heat the water such that it will serve as both hot water for the cylinder as well as provide hot water for the central heating system.
How does a system boiler differ from a combi boiler?
Combi boilers are best known for their compact size which is extremely helpful for smaller spaces that have limited space, including condos and small flats, where, fitting a header tank or a hot water tanker separately is a challenge.
Although combi boilers have the ability to provide heating as well as hot water from a single unit, there are some limitations that make them less useful for a larger family or a place where hot water is needed from multiple outlets simultaneously.
Combi boilers use a diverter valve to switch from providing heat to providing hot water, this leaves an impact on the overall performance of the combi boilers when the demand for hot water is high.
This is precisely where the system boiler has more of an advantage over the combi boiler.
This is all due to the fact that system boilers have a separate hot water cylinder for holding large volumes of hot water.
Although the system boiler comes built-in with the majority of the heating and hot water system’s components, the hot water is kept in a separate external cylinder.
This enables a plentiful supply of hot water to be delivered simultaneously to several faucets and showers.
It is, therefore, the best option for a house with simultaneous demand for hot water e.g. large family homes with multiple bathrooms that are likely going to be used at the same time.
Should you choose a system or combi boiler?
As discussed, if you have a large property with multiple bathrooms that are likely going to be used at the same time, a system boiler is typically the best option.
Below is a table showing the property type/size and the suggest type of boiler you should install:
| Property Type | Ideal Boiler Type |
|---|---|
| Small Home 1 Bathroom | Combi Boiler |
| Small Home 2 Bathrooms | Combi Boiler |
| Average Size Home 1 Bathroom | Combi Boiler |
| Average Size Home 2 Bathroom | Combi Boiler |
| Average Size Home 3+ Bathroom | Regular/System Boiler |
| Large Home 1 Bathroom | Combi Boiler |
| Large Home 2 Bathrooms | Regular/System Boiler |
| Large Home 3+ Bathrooms | Regular/System Boiler |
Factors that impact the cost of system boilers
The total cost you should expect while installing a new system boiler depends on the following factors:
System boiler size
A crucial step in the process is choosing a system boiler with the proper size and power output for your house.
In order to choose a system boiler that is the correct size for your home, consider the following rules as a general guide:
- 12 to 15 kW is ideal for smaller apartments with one to three bedrooms and one bathroom.
- 18 to 24 kW is enough for three-four bedrooms and one–two bathrooms.
- 30 kW or more is sufficient for at least two baths and four bedrooms.
System boiler performance
The size of your family and your daily hot water needs should be taken into consideration when choosing a new system boiler.
This is to ensure that you are utilizing the boiler to its full capacity and are neither overburdening nor under burdening it.
Otherwise, you might end up discovering your boiler is unable to keep up with your households hot water demands and be limited to using one bathroom at once.
System boiler warranty
A boiler will at the absolute least have a two-year warranty from the boiler manufacturer, while the majority of boiler manufacturers extend their boiler coverage up to five years.
Higher warranties are also available for premium boiler models and some boiler installation companies now offer a 10 year warranty as standard.
This includes both Heatable and Boxt.
System boiler efficiency
When size and performance are equal, the cost of the unit depends on how effectively it utilizes fuel.
The good news is that all modern system boilers utilise condensing technology and have an Erp rating of A, this means that they are at least 92% efficient.
Moving your system boiler
Boilers are not mobile and if you want to change the location of the boiler inside your space, it is not going to be an easy process.
There are additional costs involved when compared to a standard installation, this is largely due to the additional materials that will be needed e.g. copper pipework, as well as the additional labour.
The average cost of system boilers in the UK
The average cost of a standalone system boiler in the UK can range from £500 to £2,000.
There are a number of variables that play role in increasing or decreasing the cost, including but not limited to the boiler manufacturer, associated warranty period, awards and reputation.
However, this does not include Gas Safe installation, which we will now discuss.
System boiler installation costs (including boiler price)
In order to get an accurate idea of how much a system boiler installation may cost, you need to consider the following factors:
- Brand of the system boiler.
- Boiler warranty period.
- Whether you want to move the boiler to a new location.
- Whether or not it is a standard like for like swap or a more complex conversion e.g. converting from a combi to a system boiler.
Common example: a standard like for like swap:
Installing a new system boiler will cost between £500 and £1,000 on average, depending on the complexity of the installation.
For example, a like for like swap e.g. replacing your current system boiler in the same location is going to be cheaper than replacing your system boiler, together with the tank in a new location.
So to conclude, the average cost of a complete system boiler install – that includes the boiler, a cylinder, a system clean and labour, can range from £1,500 to £7,000 (excluding VAT).
How to get the best price on a new system boiler (top tips)
Understand your needs
Start by analyzing how much you will be using the boiler.
The number of people using the boiler and the space will determine the size and performance of your ideal boiler.
Choose the right boiler
Look through different options in the market and see what will work best in your space.
Make sure to choose a boiler which will be used in a balance – neither overused nor underused. Choosing the right boiler means choosing the right size, efficiency, performance and brand.
Don’t settle
It can be tempting to choose the least expensive choice if the installation is urgent or if money is limited.
A few pounds saved today on your boiler could end up costing much more in the long run if it isn’t the proper type, size, or reliability for your needs.
Your boiler is an investment that will last for many years.
Inquire about the product
Ask as many questions as you can until you are sure that you’re making the right decision.
Remember to request multiple quotations from various providers before making a final decision.
System Boiler Costs UK Conclusion
A new system boiler is an expensive purchase, so you’ll want the installation to be done expertly by a qualified contractor. Boiler installation is not a DIY project.
In order to even buy a boiler, homeowners frequently need to go through a qualified contractor, so get in touch with a few suppliers to see what they have to offer.
To learn about your alternatives, speak with as many experts as you can. They may respond to your queries and aid you in determining which model will best suit the requirements of your house.
It is strongly advised that your boiler be maintained once a year to keep it operating at its peak for longer. It is a holy grail If you can find a deal that includes some sort of annual servicing.