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  • The Best System Boiler Brands

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  • The Best System Boiler Brands

    Updated: March 10, 2023

    What are the best system boiler brands?

    The best system boiler brands are Viessmann, Worcester-Bosch and Vaillant. You can check our website for more details about specific models.

    Best System Boiler Brands Review:

    On this page you can find a number of reviews for a number of System Boiler Brands:

    Viessmann System Boiler Review:

    Viessmann Logo
    The Best System Boiler Brands 2

    Brand: Viessmann

    Model: Vitodens 100-W Gas System Boiler

    Details: The Viessmann Vitodens 100-W System boiler is both a reliable and fantastic wall-mounted gas condensing boiler. 

    These gas system boilers are available for prices around £1000. They are a great choice for any home that needs a top-quality but affordable system boiler.

    The Viessman Vitodens 100-W comes in 26kW, 30kW, and 35kW system boiler sizes.

    Not to mention that this system boiler is perfect for larger homes with more than four people, or more than one bathroom, where the demand for hot water is high and to multiple taps at the same time.

    What makes this boiler special?

    The Viessmann Vitodens 100-W System Boiler has an efficient and reliable Inox-Radial heat exchanger with MatriX cylinder burner. 

    The cylinder makes sure the heat is distributed cleanly and efficiently and won’t corrode or fail as with most other boilers.

    With a high modulation ratio of 1:6, the boiler reduces or increases its operating power for any given room environment. As a result, it reduces heating bills.

    What’s more, the LCD touchscreen makes this system boiler easy to use, and it also comes with an optional external weather detector. What does this mean? Well, it means that the detector allows the boiler to react to outside weather conditions and increase or decrease temperatures accordingly.

    This system boiler rates ‘A’ Class in the SEDBUK energy efficiency ratings.

    Main Features:

    • High modulation ratio of 1:6
    • SEDBUK A Rating
    • MatriX pre-mix cylinder burner and an integral AquaBloc hydraulic unit
    • Various Kw Heating Output -26kW, 30kW, and 35kW
    • Very Quiet Boiler
    • Optional external weather detector
    • Advanced technology
    • Which Rating 76%
    • LCD touchscreen
    • Compact size
    • Lightweight
    • 5- year parts and labour warranty as standard (Up to 10 years with Viessmann Installer)

    Overall, we would recommend this system boiler above all others due to quality, performance, lengthy warranty and price. 

    With installation, you can expect a cost between £1800-£2200 depending on the company who installs it. 

    If you’d like a new system boiler quote, then click here as we can provide you with a custom quote including installation fees for your home specifically so you can get an idea of the total cost for you. 

    Worcester Bosch Greenstar 24i System Boiler Review

    The Best System Boiler Brands 3

    The Worcester-Bosch Greenstar 24i System is one of a range of highly energy-efficient A-rated gas boilers.

    They are rated very highly by SEDBUK 2009.

    Being a system boiler, the Worcester-Bosch Greenstar 24i System needs a hot water storage cylinder. But it doesn’t require a feed and expansion cistern.

    This makes the Greenstar 24i a quick and easy to install as well as being efficient and economical to run.

    What this system boiler special?

    With the Worcester-Bosch Greenstar 24i, heat from exhaust gases, that would otherwise be lost through the flue, are recycled. This heat is then used as output, powering your domestic hot water and central heating with what otherwise be wasted energy.

    This means that the Greenstar 24i is up to 30% cheaper to run than some older boilers.

    We rate this boiler lower than the Viessmann because the Viessmann has a much better stainless steel heat exchanger with better reliability than the Worcester Bosch. 

    The price comes in around £1,050 on average with an installed price being around £2000. 

    Get an online quote:

    Main Features:

    • ERP rating: A HEAT
    • Efficiency Rating: 94%
    • Band Rating: A Rated
    • LPG Compatible: Yes
    • Standard Warranty: 5 Years
    • kW Options: 24.6 kW
    • Mounting: Wall-mounted

    Overall, with the price and efficiency, we recommend this boiler in 2nd place to the Viessmann.

    You can rest assured that this information is reliable and will provide you with a fantastic new system boiler. 

    Vaillant ecoTEC Plus System Boiler Review

    Vaillant Logo 2005
    The Best System Boiler Brands 4

    The ecoTec boiler range from Vaillant is a fantastic and low energy consumption system boiler for 2022.

    It has excellent performance for hot water and central heating – and lower fuel bills for you. 

    The Vaillant ecoTec 30kW is the most popular size boiler in this range, but it is also available as 12kW, 15kW, 18kW, 24kW, 30kW and 37kW.

    The ecoTEC plus is smart: when it knows you don’t need as much heating power, it can drop to using 16% of its maximum power saving on fuel and money.

    It is known by our installers to be efficient, easy to use, reliable and quiet.

    With its straightforward backlit display and like the Viessmann, its stainless-steel heat exchanger and it’s premium components, it’s really one of the top system boilers available on the market today.

    We only rated this in third place because of the initial cost.

    Not to mention that it has a better heat exchanger than the Worcester Bosch however its initial cost is almost £500 more than the other two system boilers. 

    Pricing is around £1500 with an installed price of £2000+

    System Boilers Features:

    • For use with Unvented Systems.
    • Stainless steel heat exchanger
    • Advanced modulation during low usage to ensure maximum efficiency
    • New high-efficiency pump to reduce energy consumption
    • Stylish contemporary case design to ensure a seamless fit with home decor
    • ErP Compliant
    • Lightweight and compact
    • Natural Gas fueled
    • Includes 2 stage frost thermostat
    • Built-in pump and expansion vessel
    • Compatible with Unvented systems

    Overall, an excellent boiler with reliable internal components means you can’t go too far wrong with the Vaillant EcoTec series system boilers.

    Want a system boiler?

    If you are interested in a System Boiler Install or another different type of boiler install please feel free to start an online quote or feel free to contact us!

    What are the other types of boilers?

    What is meant by a Condensing Boilers?

    The terms condensing and non-condensing can be confusing to people shopping for a new boiler.

    Presently, it is stated by law that new boilers must use condensing technology. In short, you don’t have to worry about getting a condensing boiler.

    Condensing is not a type of boiler, but rather technical feature. In a Condensing boiler you get a much bigger heat exchanger. They also produce additional heat from the fuel. The same fuel that would have been wasted in a non- Condensing boiler. As a result, they are more efficient.

    non-condensing boilers are less efficient by 50% since a lot of heat was lost in the combustion exhaust gases. On the other hand, new boilers would capture this heat and use it to heat water.

    condensing boilers are energy efficient by 90%. They use excess energy to heat your property. Not to mention, they are environmentally friendly and reduce your heating bill.

    Can I get the next-day boiler installation?

    Yes, you can If you order your boiler before 12 pm during the colder months, and 2 pm in the warmer months.

    This is next-day boiler fitting nationwide in England, Wales and Scotland. So you do not have to be without heating for long, even in the depths of winter.

    Not many boiler companies can fit a boiler at such short notice nationwide. If you need a boiler, get a quote from us as soon as possible.

    Get an online quote:

    So why Let’s Heat?

    Let’s Heat Are Quality & Accredited Boiler Installers

    Firstly, Let’s Heat professional engineers and emergency plumbers provide a professional and reliable plumbing and heating service. Accordingly, that includes Boiler Installation in Cardiff and the surrounding CF postcode area in South Wales.

    Secondly, our boiler installation and repair team is fully qualified and ensured to the highest standards. As can be seen, we take pride in producing exemplary work standards which include completing all boiler installation needs. 

    Thirdly, the Let’s Heat team are high-quality professional engineers who have a high 4.9 out of 5 Trustpilot score by our previous happy customers. We are fully accredited by Gas Safe and Corgi registered, as well as FCA approved for all of our financial transactions. 

    Lastly, all of our staff at Let’s Heat are experts in their field and have many years of experience. Above all, we have work on a wide selection of emergency plumbing, heating solutions and services throughout Cardiff, the rest of Wales & the UK.


    Are system boilers efficient?

    System boilers have an efficiency rating of 94%. If you want to boost your home’s efficiency, then you can invest in a new energy-saving system boiler.

    What are the advantages of a system boiler?

    One of the main advantages of having a system boiler is that Hot water is always available. What’s more, they energy-efficient and environmentally friendly. They also don’t require a cold water tank. Lastly, flow rates tend to be high and at mains pressure.

    Can a system boilers heat water and radiators at the same time?

    System boilers are able to maintain both the radiators and water without losing pressure. System boilers, without a doubt, do not prioritise where heat is distributed. But they can run out of hot water if you use more than is there in the tank.

    Can I use a power shower with a system boiler?

    Yes, system boilers are compatible with power showers.

    Does a system boiler need a tank?

    Different from regular boilers, system boilers neither need an expansion tank nor external expansion vessels. As a result, they are both easier to install and need less space.