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  • Viessmann System Boiler Review:

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  • Viessmann System Boiler Review:

    Updated: April 6, 2024

    Viessmann System Boiler Review:

    Founded in 1917, Viessmann is headquartered in Allendorf, Germany and has been a family-owned company since its inception.

    Today, the company manufactures heating, industrial and refrigeration systems and operates in 74 countries across the world.

    Viessmann has operated in the UK since 1989 and from its UK headquarters in Telford, the company offers a product range including gas boilers, oil boilers, air and ground source heat pumps, steam boilers, biomass boilers and combined heat and power generation.

    Each year, Viessmann trains approximately 2,500 installers, contractors, specifiers and architects on its products across the UK.

    Whilst not as well-known in the UK as Worcester Bosch, Viessmann is increasingly gaining traction across the UK – this is in part due to its entire Vitodens range being awarded Which? Best Buy status every year since 2017.

    Over the past decade, Viessmann has invested heavily in its technology and offers products providing market-leading efficiency levels.

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

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

    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 multiple taps at once.

    What do we love about this boiler?

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

    The cylinder ensures 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. This reduces heating bills and wear and tear.

    The LCD touchscreen makes this system boiler easy to use, and It also comes with an optional external weather detector. What does this mean? 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.

    Read more:

    Different Types Of Reliable Boiler Systems

     Best Brands of System Boilers & Pricing

    The Advantages of System Boilers

    A large supply of hot water

    Generally, with a system boiler you can store large quantities of hot water to use later on. This is very useful when you are using multiple taps, showers and radiators at the same time.

    The ability to use solar energy.

    Without a doubt, connecting the correct cylinder to the system will enable you to use solar panels. This is not only environmentally friendly but it is also cost-effective and will save you some money.

    Needs less space than a regular boiler

    Of course, system boilers are easier to install and need less space than regular boilers. Moreover, they do not need an expansion tank or external expansion vessels

    Economical and fast

    Lastly, system boilers consist of a pump. As a result, they respond fast and have more economic running cost.

    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.

    viessmann boilers review

    Can I get the next-day boiler installation?

    Yes, you can get next-day boiler installation with Let’s Heat. 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.

    Installation energy regulations

    Over the last few years, the UK has passed some guidelines for boiler installation and energy efficiency:

    • Gas boilers should have at least a 92% ErP efficiency regardless of boiler type.
    • A Combi boiler installation should have one energy-saving feature.
    • You should have functioning time and temperature controls.How long should it take?

    How long should it take?

    Boiler installations can take different amounts of time to complete due to such a varied amount of work for each particular home or business.

    Replacing an already-existing combi boiler with a new one should take 3-6 hours.

    Replacing a heat-only boiler with a combi or a system boiler would take 1-2 days.

    The full range of heating & plumbing services provided by Let’s Heat are as follows:

    • Boiler Repairs & Installations
    • Emergency Kitchen Plumbing
    • Boiler Supply & Fit
    • Boiler Finance
    • Emergency Boiler Repairs & Installations
    • Emergency Boiler Supply & Fit
    • Plumbing Repairs
    • Bathroom Plumbing
    • Kitchen Plumbing
    • Emergency Plumbing Repairs
    • Emergency Bathroom Plumbing
    • General Plumbing Services
    • Emergency Plumbing Services
    • Emergency Gas & Heating Engineer

    Read about:

    Worcester Bosch Greenstar System Boiler

    Worcester Bosch Boilers Review

    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.

    Because we care

    Are you still a little confused about where to start or who to use?

    Our easy-to-use online questionnaire will help you with what you need to know. In short, we make sure that you have the correct solution for your needs. We will also ensure that you are completely happy with the solution.

    Why else?
    • We work in Cardiff and the surrounding areas of South Wales.
    • We are reliable, professional and trustworthy.
    • High Trustpilot score of 4.9 out of 5.
    • We can travel anywhere throughout the UK.
    • Gas Safe Accredited (corgi registered).
    • Our finance is FCA accredited.
    • We provide a 12-month snag guarantee.
    • Our prices are very competitive.
    • We make sure your house is kept clean and tidy during work.
    • Our workmen use floor protection.
    • We dispose of your rubbish correctly.

    Have any further questions, please see our FAQ Page – Want to check our Gas Safe Registration or want to see our near 5 star Trustpilot rating please click the links!


    How does a Viessmann system boiler work?

    The water is heated via a heat exchanger, which transfers energy from the gas jets to the water. Once heated, the water is pumped to the hot water cylinder, where it is stored until needed.

    Is Viessmann a good company?

    Every Viessmann boiler is ENERGY STAR® certified, was awarded the ENERGY STAR Most Efficient of 2020, and has an AFUE rating of 95 or 98 percent.

    What is the life of a Viessmann boiler?

    A typical boiler’s lifetime is expected to be 15-20 years. However, things vary, and your boiler might last longer if it is well maintained, less if it is ignored. Once repairs are needed more frequently, or if they become increasingly expensive, then a replacement boiler may save you money in the long run.

    How efficient are Viessmann boilers?

    Viessmann boilers come with the expertise and technology that has grown and developed over the last 100 years. Some boilers can reach an efficiency rating of 97%, which make them amongst the most efficient on the market and they’re accompanied with lengthy warranties as well.

    Are Viessmann boilers made in Germany?

    Viessmann boilers were founded in Germany, but are now manufactured in 12 different countries, they also have a factory and offices in Telford, UK.