Top 10 Best Conventional Boilers
We’ve compiled a list of the top 10 conventional boilers available in 2024. This list is based on factors such as efficiency, reliability, as well as the best conventional boiler reviews.
1. Viessmann Vitodens 100-W Compact WB1B
Viessmann was founded in 1917 and is one of the leading boiler manufacturers. The Vitodens 100-W is one of its most popular models, and is available as a combi or system boiler, as well as conventional.
This conventional boiler is available in output sizes of 13kW, 16kW, 19kW, 26kW, and 35kW, making it suitable for a range of homes. Therefore, you’re likely to find a sufficient output size whatever your hot water demand may be.
Furthermore, this conventional boiler is one of the most efficient, as it is A-rated with a 94% efficiency rating. This means only 6% of the energy you use is wasted, which in turn means you also only waste 6p per £1 you spend on your heating bills.
Viessmann also provides a standard warranty of 5 years for all of its boilers. However, for this model it can be extended to 10 years if installed by a Viessmann Academy Trained Installer. This reflects Viessmann’s confidence in the reliability and longevity of its boilers.
What more, the Vitodens 100-W range is capable of working with a 20% hydrogen blend. As we all know, gas is not the best fuel type for the environment, which is why the UK’s National Grid is hoping to switch to a hydrogen blend in the coming years. Many boiler brands, including Viessmann, are creating boilers that can function with a hydrogen blend and are working towards 100% hydrogen ready boilers.
Its notable features include:
- A stainless steel Inox-Radial heat exchanger which is highly resistant to corrosion.
- A MatriX-Plus cylinder burner which helps to ensure that heat is distributed efficiently.
- LPG (liquefied petroleum gas) compatibility. LPG is more environmentally-friendly compared to oil.
2. Vaillant ecoFIT pure
Vaillant is another well-renowned boiler brand with a few popular models to choose from. One of which is the ecoFIT pure conventional boiler.
This model has a wide range of output sizes to choose from including 12kW, 15kW, 18kW, 25kW, 30kW, and 35kW.
As the name might suggest, the ecoFIT pure is highly efficient. It has an efficiency rating of 94% and ErP (Energy-related Products) A-rating for heat. Therefore, making it one of the best available conventional boilers for reducing your energy bills and carbon footprint.
The standard warranty for the ecoFIT pure may only be 2 years, however, as Vaillant is confident in its products and installers this can be extended up to 10 years if installed by a Vaillant Advance Installer.
All of Vaillant’s existing condensing boilers have been tested to ensure they operate correctly with a 20% hydrogen blend. Furthermore, Vaillant is currently working on launching a 100% hydrogen ready boiler.
Its notable features include:
- An aluminium heat exchanger to help lower energy usage.
- A rear flue option for flexible installation.
- Simple controls for maximum control.
3. Vaillant ecoTEC plus
The ecoTEC plus is another well-reviewed model from Vaillant. It meets the same efficiency standards as the ecoFIT pure, with a 94% and A grade ratings. It is also available in similar output sizes of 12kW, 15kW, 18kW, 24kW, 30kW, and 35kW.
In terms of warranty length, the ecoTEC plus is also considered to be a reliable model. It has a standard warranty of 5 years, and like the ecoFIT pure this can be extended up to 10 years under the condition that it is installed by a Vaillant Advance Installer.
Its notable features include:
- A wide modulation range of 1:6 which minimises fuel consumption and maximises efficiency.
- A two-stage frost protection which helps protect loft and garage installations all year round.
- A wide range of heating control options including a smartphone app.
4. Worcester Bosch Greenstar 8000 Life
Worcester Bosch is a well-established boiler brand which is leading the way in making a more sustainable future for boilers. Its hydrogen-ready boiler prototype won the award for Best Heating Innovation at the Green Home Awards in 2021.
This model is available in output sizes that are appropriate for medium and larger sized homes: 30kW, 35kW, 40kW, 45kW, and 50kW.
As the name implies, the Greenstar 8000 Life is A-rated and has an excellent efficiency rating of 94%. Therefore, you can feel assured that you are getting the most out of your energy and not overspending on heating bills.
You can rely on the Greenstar 8000 Life as it comes with a standard warranty of 5 years which can be extended up to 12 years if installed by a Worcester Bosch Accredited Installer.
As mentioned, Worcester Bosch is leading in sustainable innovation for boilers, therefore it’s no surprise that its entire gas boiler range is capable of running on a 20% hydrogen blend including this model.
Its notable features include:
- A modulation ratio of 1:10 which enhances efficiency.
- On/off cycling prevention which helps increase the boiler’s lifespan.
- Easy access to all internal components as the top, front, and side panels can all be simply removed which is helpful for when your boiler needs serviced.
5. Worcester Bosch Greenstar Ri
Another popular conventional boiler from Worcester Bosch is the Greenstar Ri. However, its stats do differ slightly from the previously mentioned model.
The Greenstar Ri is more suitable for homes with a lower heating and hot water demand as it is available in smaller output sizes: 12kW, 15kW, 18kW, 21kW, 24kW, 27kW, and 30kW.
Like the Greenstar 8000 life it is A-rated, however, it has a slightly lower efficiency rating of 92%. This is still considered to be a good efficiency rating overall, however, it does mean this model is likely to waste marginally more energy. With this being said, if you want to minimise the amount of energy that’s wasted in your home, then focusing on factors such as your home’s insulation will have a much bigger impact.
This model also has the standard 5 year guarantee and can be extended up to 10 years, under the condition it is installed by a Worcester Bosch Accredited Installer.
Its notable features include:
- Compatibility with Greenskies solar panels to reduce your carbon footprint.
- Frost protection which helps protect boilers that are installed in a loft or garage.
- LPG compatibility.
6. Baxi 800
Baxi is a British brand who specialise in making boilers. It has received many awards over the years including the Net Zero Hero award in 2020.
This boiler is only available in three sizes which are 16kW, 25kW, and 30kW. Therefore, it’s suitable for smaller and medium sized homes.
Similar to the other top conventional boilers, the Baxi 800 is also A-rated and has an efficiency rating of 93%. This means that you’ll only waste 7% of the energy you use for heating your home.
Baxi offers extensive warranties of 10 years with its boilers, giving you peace of mind that your boiler will be covered throughout its lifespan.
Furthermore, the Baxi 800 range is certified for use with 20% hydrogen blends. This means that you’ll already be prepared for when the National Grid switches to a hydrogen and natural gas blend.
Its notable features include:
- An ADEY Micro2 compact system filter which helps protect your unit from any faults developing.
- Being extremely quiet whilst operating.
- A rear flue option for a neat finish.
7. Ideal Logic Max Heat
Ideal is another British brand which has many years of experience producing boilers. The Logic Max range is available as a combi or system boiler, as well as a conventional boiler.
The conventional version is available in a number of different output sizes: 12kW, 15kW, 18kW, 24kW, and 30kW.
If you opt for the Ideal Logic Max then you’ll be receiving an ErP A-rated boiler with a 93% efficiency rating. This means you’re only wasting 7p for every £1 that you spend to heat your home.
You can trust in the reliability of this boiler as Ideal offers a 10 year warranty when you install this product, meaning it will be covered throughout its lifespan.
In addition, this model is ready to run safely on a 20% hydrogen blend with no technical adjustments.
Its notable features include:
- A large digital display, giving you maximum control.
- Being hard wearing and scratch resistant.
- An easy to reach pressure gauge on the front panel.
8. ATAG iR
ATAG has been designing and manufacturing boilers for almost 70 years. This boiler brand has gained a lot of support from its customers as it boasts being the UK’s highest rated boiler brand on Trustpilot.
This conventional boiler is available on the UK market in a range of sizes suitable for both smaller and larger homes: 15kW, 18kW, 24kW, 32kW, 40kW.
This model has an excellent efficiency rating of 94% and an ErP (Energy-related Products) A-rating for heat. This means it has the potential to reduce your carbon footprint and energy bills.
You can feel assured by ATAG’s confidence in its products. A 10 year warranty is offered as standard with the option of extending it to 14 years.
ATAG offers appliances that are capable of functioning with at least a 20% hydrogen blend and claims that its boilers can be easily modified to support 100% hydrogen in the future.
Its notable features include:
- Bottom-up modulation which leads to quiet operation.
- The ATAG iCon stainless steel heat exchanger, which comes with a unique lifetime replacement guarantee.
- LPG and solar compatibility.
9. Johnson and Starley QuanTec
Johnson and Starley takes pride in the reliability, efficiency and value for money of its boiler ranges. Its boilers are British made and its QuanTec range has a reputation for being easy to install and maintain.
This boiler is only available in two output sizes, namely 16kW and 24kW. The first being more suitable for homes with up to 10 radiators, and the second for homes with up to 15 radiators.
The QuanTec boiler is A-rated and has an impressive efficiency rating of 94%. This means only 6p is wasted per £1, making it a more cost-effective boiler.
Johnson and Starley also provides a parts and labour manufacturer-backed warranty of 8 years for this conventional boiler.
Its notable features include:
- A stainless steel heat exchanger with cool door technology.
- Vertical, horizontal, and flexible flue options.
- A compact size of 780x423x321mm and weight of 39kg means installation is both easier and cheaper.
10. Heatrae Sadia Amptec electric boiler
Heatrae Sadia Amptec is the one electric conventional boiler to make the list. This is especially a good choice to consider for homes without a mains gas supply.
This model is available in a few different output sizes: 4kW, 6kW, 9kW, 11kW, and 12kW. It’s important to note that all of the sizes are generally more suitable for smaller homes.
As is typical for many electric boilers, the Heatrae Sadia Amptec has a fantastic efficiency rating of 99.8%. However, you should also consider how your electricity is generated. Electric boilers typically come with a D-rating as the majority of electricity generation involves the burning of fossil fuels. Therefore, to avoid this and be as environmentally friendly as possible, we advise you to look into getting your electricity from green energy suppliers.
Unfortunately, the warranties offered by smaller electric boiler companies tend to be a lot shorter compared to gas boilers. For this particular model the warranty length is 2 years. However, this isn’t necessarily a reflection of the quality or lifespan of your electric boiler, with many electric boilers being known to last for 8+ years.
Its notable features include:
- Compatibility with wet central heating systems, including underfloor heating and conventional radiators.
- Being made up of long thin units with a footprint of 90mm² so doesn’t require too much space.
- Being silent during operation.
After reading this list, hopefully you have a better idea of which conventional boiler models are out there. However, it may have also raised some new questions, such as “which output size is best for my home?” and “which installers are certified for longer warranty lengths?”. It can be difficult and time consuming to answer all of these questions yourself, never mind finding installers on top of it – that’s where GreenMatch comes in.
Simply click the button below and fill in your details only once. You’ll then receive up to 4 free quotes from qualified local installers and compare them side by side within 5 minutes.