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  • What is the best system boiler?

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  • What is the best system boiler?

    Updated: April 11, 2024

    System boilers are a popular choice in the UK, particularly for larger homes, as they have the capacity to supply hot water to multiple bathrooms and taps simultaneously. If you’re in the market for a system boiler, you may be wondering: which system boiler is the best option for your needs?

    System boilers are widely favored in the UK due to their ability to efficiently supply hot water to multiple bathrooms and taps, making them ideal for larger homes. If you’re considering purchasing a system boiler, you may wonder which brand offers the best choice. In this blog, we’ll delve into the top brands known for their efficiency, reliability, and overall performance. Additionally, we’ll explore factors influencing the price of system boilers, including kW output, warranty coverage, and installation expenses.

    What is a system boiler?

    A system boiler consists of a separate cylinder that is used to store hot water. Most of the major heating parts are built into the boiler. However, the hot water is stored in the cylinder in order to provide a constant hot water supply for your taps and showers. That is why it is ideal for large homes that have a high hot water and heating demand.

    How do system boilers work?

    A system boiler draws its cold water supply directly from the mains. Once inside, the heat exchanger within the boiler warms up the water. This heated water is then stored in the hot water cylinder, readily available for use when needed. An electric pump is employed to circulate the hot water to your taps and radiators. Notably, system boilers utilize condensing technology, enhancing their energy efficiency.

    What Are the Advantages of System Boilers?

    Ample Hot Water Supply: System boilers typically allow for the storage of large quantities of hot water, making them ideal for households with multiple taps, showers, and radiators in simultaneous use.

    Solar Compatibility: By connecting the appropriate cylinder to the system, you can harness solar energy, promoting eco-friendliness and cost-effectiveness.

    Space Efficiency: Compared to regular boilers, system boilers require less space for installation as they eliminate the need for expansion tanks or external vessels.

    Economical and Swift: Equipped with a pump, system boilers offer rapid response times and boast economic running costs.

      Factors to Consider:

      Space Requirements: While system boilers are more space-efficient than regular boilers, they still demand more room than combi boilers due to the presence of an external cylinder, which may pose challenges in smaller homes.

      Patience During Busy Periods: Although the hot water cylinder is pre-sized to meet household demands, peak usage periods may lead to temporary depletion of hot water storage, necessitating a wait time of 30-40 minutes for the boiler to reheat the cylinder.

      Read about: Top UK System Boilers

      What is the best system boiler brand?

      1. Worcester Bosch

      Worcester Bosch is a United Kingdom based heating and hot water products manufacturer. The company was established in 1962 by Cecil Duckworth as Worcester Engineering Co Ltd in Worcester, England.

      Worcester Bosch is the UK market leader in domestic boilers. They have earned recognition and high acclaim over the last 50 years. Moreover, they have won multiple awards.

      Worcester Bosch range of system boilers:

      • Greenstar 8000
      • Greenstar 8000 Style
      • Greenstar 8000 Life  
      • Greenstar i       
      • Greenstar Danesmoor (oil boiler)       
      • Greenstar Danesmoor External (oil boiler) 
      • Greenstar Danesmoor Utility (oil boiler)      
      • Greenstar Condens 7000 WP (oil boiler)

      What is the output range on Worcester Bosch system boilers?

      System boilers are ideal for medium sized homes with a high demand for hot water and heating. A system boiler operates alongside a hot water storage cylinder in order to ensure that enough hot water is available when needed.

      • The Greenstar 4000 system boiler has an output of 12 – 24kW and can support up to 12 radiators.
      • The Greenstar 8000 system boiler has an output of 30kW and can support up to 15 radiators.

      The Greenstar 4000 System boiler

      The price for the Greenstar 4000 ranges between £975 – £1,200. As for the installation cost it is between £500 to £1,000, depending on different factors.

      This is one of the best and most powerful Worcester Bosch boilers. It has also won the Which? Best Buy award in 2022. With this model you will get a number of benefits.

      The Greenstar 4000 is available as both a system and a combi boiler. It is suitable for most types of homes.

      Read more: The Best Brands of System Boilers & Pricing

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      What is the best system boiler

      What are the key features of the Worcester Bosch Greenstar 4000?

      • This model is very quiet
      • Has a 10 year guarantee (given that it is installed by accredited worcester installer
      • Has an A-rated efficiency on the ErP scale. This feature can save you money on energy bills because your boiler will waste very little energy
      • Compact and easily installed
      • 20% Hydrogen ready
      • It can be connected to Greenskies solar panels
      • When combined with a hot water storage cylinder, your system will be able to provide for multiple bathrooms
      • This system can be used with wireless smart control using Bosch EasyControl

      The Greenstar 4000 boiler offers a range of output options so that you can choose the one that best fits your home. By choosing the right level of power, you will be able to save money due to reduced heating bills.

      • Viessmann

      Whether we are talking about domestic or commercial heating solutions, Viessmann Boilers are known for their high quality and outstanding performance. They produce a range of products that include boilers, hot water cylinders, heat pumps, photovoltaics and solar thermal systems.

      To bring down the cost of energy and to reduce your heating bills, Viessmann produces boilers that are highly efficient. By using the latest technologies Viessmann aims to provide innovative heating solutions.

      Vitodens 200-W B2HE System boiler

      For medium homes with high energy demand this can be a great option. The Vitodens 200-W B2HE System can support 1 bathroom and up to 15 radiators. It has a central heating output of up to 32kW and a domestic hot water output of up to 29 kW. It goes without saying that this is the most powerful system boiler made by Viessmann. The cost for the Vitodens 200-W B2HE System can be between £1,344 – £1,650 without the cost of installation.

      What are the key features of the Vitodens 200-W B2HE System boiler?

      • Warranty of 5 years, and can be extended up to 12 years
      • Central heating output available in 11, 19, 25, 32 (kW)
      • Energy efficiency: A-rated
      • By using ViCare thermostat it can be Wifi-enabled
      • Can achieve better efficiency with Inox Radial heat exchanger
      • Internal combustion control using Lambda Pro Plus
      • Less pollutants with MatriX plus burner

      Viessmann system boilers output range

      Viessmann system boilers have an output range of 11kW to 32kW. This range can be suitable for small and medium sized homes as well.

      • The Vitodens 200-W B2HE has central heating power output of 11 kW and can support homes with 1 bathroom and 5-10     radiators.
      • The Vitodens 100-W B1HC has a central heating power output of 32 kW and can support homes with 1 bathroom and 10-15 radiators.
      • Vaillant

      Vaillant has more than 140 years of boiler and central heating experience. They helped and paved the way for the introduction of the combi boiler. Vaillant has been working on more environmentally friendly solutions. They have a wide range of air source heat pumps.

      Vaillant is the second largest boiler manufacturer in Europe and they operate in more than 20 countries.

      Vaillant boiler range

      Vaillant has 2 main boiler models to represent their boiler range:

      • The Vaillant ecoTEC
      • The Vaillant ecoFIT

      These two models are available in combi, system and regular boiler types. You can also get the ecoTEC as a storage combi boiler with an integrated hot water tank.

      Whether you are looking for a combi, system or regular boiler, Vaillant has a popular model for each type.

      The ecoTEC plus also takes the first spot for their most selling system boiler. This type is available in different outputs so that you can choose which model suits your home the best. It has the ability to reduce your energy consumption due to its built-in advanced modulation that can save you money on energy bills.

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      How much do Vaillant system boilers cost?

      Vaillant system boilers have a price tag that ranges between £900 to £2,700, depending on the size and the output. The higher the output, the more money your boiler will cost.

      Read more: New Boiler Cost

      What is the output range on Vaillant system boilers?

      The output range for Vaillant system boilers is between 12kW to 64kW. That is why they are suitable for properties which have between 6 and 42 radiators.

      System boilers are excellent when it comes to providing large amounts of hot water or heating to your home. They do not require a feed tank in the loft which makes them very practical. What is more, they are an excellent option for replacing a combi boiler that is unable to meet your demand for hot water and heating.

      • Ideal

      Ideal Heating manufactures high-quality boilers for domestic use. They have a wide range of boilers that includes combi, system and regular boilers. If you are interested in Ideal boilers, then you have come to the right place.

      Ideal offers various options to suit your heating needs. You will be able to choose from boilers with different efficiency ratings, outputs, fuel types, warranties and prices. Whether you live in a small or a large home, Ideal has the perfect heating solution.

      Ideal System Boilers

      • Logic Max System
      • Logic+
      • Vogue Max System
      • Vogue Gen2

      Ideal Logic system gas boilers

      This range of Ideal system boilers is lightweight and compact in design so there will be no need for compartment ventilation. As a result, it can be fit into small places like your kitchen cupboard. This Ideal Logic System boiler is endorsed by the Energy Saving Trust. An additional feature of this range is the PRV wall outlet pipe that would help with installation.

      The Logic system models are A-rated and have central heating outputs of 15kW, 18kW, 24kW, and 30kW. So it is best suited for medium sized homes with 10 to 20 radiators. The price for the Logic system is between £785 – £920 (without installation).

      Read about: Best combi boilers & boiler brands

      What are the key features of the Ideal Logic system gas boiler?

      • Standard 2 years warranty
      • Uses gas as fuel; compatible with 20% hydrogen blend
      • A-rated energy efficiency
      • Easy-to-see pressure gauge
      • Full backlit display
      • Boiler frost protection
      • Fully modulating temperature

      Ideal system boilers output range

      System boilers that are produced by Ideal have different outputs, ranging from 15kW to 32kW. As a result, this range of regular boilers is suitable for homes with 10 to 17 radiators. Ideal system boilers are also perfect for homes with multiple bathrooms and high hot water demand thanks to their hot water cylinder that stores hot water for later use.

      • Baxi

      Baxi has been in the boiler business since 1866. Their customer service is award winning and they are one of the leading manufacturers of heating solutions in the UK. Baxi boilers are a popular option for many homes in the UK.

      Baxi produces different types of boilers (combi, system and regular) that come in a wide range of outputs to suit your home. Baxi boilers are also known for being easy to maintain and install. Their range of light lift weight models allow easier installation. Moreover, Baxi boilers are recognised for being affordable when it comes to their cost.

      Baxi system boiler models

      • Baxi 600 System
      • Baxi 800 System
      • Baxi Megaflo System

      Baxi Megaflo System Boiler

      This range of baxi boilers is suitable for homes with multiple bathrooms and high hot water demand. To achieve powerful water pressure they can be installed alongside an innovative Megaflo Eco cylinder. And since they are compatible with multiple flue types, they offer a range of installation options.

      Baxi system boiler output range

      Baxi’s range of system boilers have an output of 12kW to 32kW. They are suitable for most types of homes. Nonetheless, they do require some space for the hot water storage cylinder. System boilers are ideal for large homes since they have a hot water storage that can supply multiple outlets.

      • The Baxi Assure System 12 model has a power output of 12.9kW that can heat homes with 1 bathroom and 6-12 radiators.
      • The Baxi Platinum+ 32kW System model has a power output of 32kW that can heat homes with 2 bathrooms and 15-20 radiators.

      Read more: Different Types Of Reliable Boiler Systems Explained and their Costs

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      Why choose Lets Heat?

      Why Choose Let’s Heat?

      Punctuality: We prioritize simplicity and quality in our work. Utilizing the latest management systems, we schedule jobs, confirm appointments, send reminders, issue certificates, and bills promptly. Offering next-day installations and emergency services, we respond quickly to your call and arrive at your doorstep promptly.

      Customer Care: Building strong relationships with our customers is our top priority. We take the time to understand your heating requirements and strive to minimize disruption and noise during our work in your home.

      Experienced Staff: With extensive experience in the heating industry, we’ve expanded our services nationwide. Committed to excellence, our engineers are knowledgeable, skilled, and informative. From boiler installation,

      maintenance, repair, and service plans to working with various boiler types like heat-only, system, and combi boilers, as well as installing heat pumps and central heating systems, we offer comprehensive solutions. Additionally, we provide plumbing services and more.

        Read about: Best Condensing Boilers

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        Who makes Ideal boilers?

        Ideal Boilers is a British company that manufactures its products in Yorkshire. The company has been in the heating business for a long time, stretching back more than a century, and is a very well known name in the UK.

        Which Ideal boiler has a ten-year warranty?

        The Ideal Logic Max System Boiler has a 10 year warranty, it is a compact cupboard fit, making it both a discrete and reliable option for your home.

        Which boiler is better, Ideal or Worcester Bosch?

        Both brands are British and considered to be among the top four boiler brands in the UK.

        Who makes Viessmann boilers?

        The Viessmann Group is a German manufacturer of heating and refrigeration systems located in Allendorf (Eder), Germany.

        Are Viessmann boilers energy efficient?

        All Viessmann boilers have an ErP rating of A or higher and an efficiency rate of at least 98%.

        Who makes Baxi boilers?

        Baxi is part of BDR Thermea Group.BDR Thermea Group is a world leading manufacturer and distributor of smart thermal comfort solutions for domestic and commercial use.

        How do Baxi boilers work?

        The boiler heats the water in a hot water storage cylinder, such as the Megaflo Eco, which then heats the water in the central heating system using a coiled heat exchanger to provide hot water to taps and showers.

        What is the most powerful Vaillant boiler?

        The Vaillant ecoTEC Plus 938 is a powerful and highly-efficient condensing combi gas boiler. It has an innovative integrated hot water storage device which is able to deliver up to 20 litres of hot water per minute and supply hot water in a time frame of only 5 seconds!

        What is the difference between Vaillant and Worcester?

        A key difference between Worchester Boschand Vaillant boilers is the heat exchanger in Worchester boilers is made from aluminium, while Vaillant boilers have stainless steel heat exchangers.

        What is the difference between Worcester Bosch 4000 and 8000?

        The key difference between the two models is the availability of power outputs. The 8000 is more powerful and made for larger homes that have a higher demand for heating and hot water.

        What temperature should a Worcester boiler be set at?

        For combi models, the hot water temperature can be set to between approx. 40˚C and 60˚C using the temperature control .

        What are the different types of Worcester Bosch boilers?

        At Worcester Bosch manufactures Combination (Combi) boilers, System boilers and Regular boilers. All three types vary and are suited for different homes and living situations.