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Last updated: 3 November 2023

42kW Boilers – Everything You Need to Know

42kW boiler

No luck so far looking for a 42kW boiler? Good news! You’ve just found the right place to start. In this article, you will find many 42kW boiler models that might be the right fit for your home.

Before going any further, we have to be fair: finding a 42kW boiler is not an easy task for most people. These are very powerful boilers suitable mostly for really large houses. Thus, not finding too many of them around is completely normal.

At GreenMatch we are a team of experts with several years of experience researching and comparing domestic energy solutions of all types and sizes. In this article, we have put together a list of 42kW system boilers, 42kW combi boilers, and 42kW heat-only boilers from top boiler brands in the UK. Compare them to find the best one for your home.

As well as comparing boilers, it’s also crucial to compare different installers and their rates so that you know you’re getting the best value for your money. However, researching and contacting multiple installers can take up hours of your precious time. Thankfully, it doesn’t have to be this way – let GreenMatch help you.

At GreenMatch we have a vast network of qualified heating engineers across the UK. This means we can easily connect you with up to 3 qualified installers available in your area whose quotes you can directly compare. Our service is completely free and non-binding (and frees up your time for the more important things in life). Click the button below to get your free quotes now.

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42kW System Boilers

System boilers can run your radiators and provide multiple taps and showers with plenty of pressurised hot water. This feature makes them an excellent option for medium-to-large homes with 2 or more bathrooms. However, they need to work alongside a hot water storage cylinder, which might not be the most space-saving component.

A 42kW system boiler can comfortably meet the central heating (CH) and domestic hot water (DHW) of a large house. However, you may end up unnecessarily paying a lot of money for extra power if what you really need is a boiler for a small house

We have put together some 42kW system boiler models so that you can compare them:

1. Intergas Compact HRE SB 40kW system gas boiler

Intergas Compact HRE SB 40kW system gas boiler

This Intergas 42kW system gas boiler is a highly reliable unit that comes with a built-in frost thermostat which helps to protect the boiler through the cold winter months. It also has almost no standby losses, and you can choose between a horizontal and vertical flue pipe.

  • Max. CH output: 42.5kW
  • Suitable for: Medium-sized properties
  • Efficiency: 92% efficiency and ErP A-rated for heat
  • Warranty: 10-year warranty on the heat exchanger and a 7-year warranty on parts
  • Estimated price (Exc. installation): £1,135 (Incl. VAT)

2. Viessmann Vitorondens 200-T 42kW system oil boiler

Viessmann Vitorondens 200-T 42kW system oil boiler

The Viessmann Vitorondens 200-T 42kW system boiler is a highly-efficient condensing oil boiler. It features a self-cleaning stainless steel heat exchanger for the utilisation of condensing technology. Additionally, its dimensions are fairly compact for a boiler with its output rating (kW).

  • Max. CH output: 42.8kW
  • Suitable for: Larger homes with more than 1 bathroom and high demand for heating and hot water
  • Efficiency: 97% efficiency and ErP A-rated for heat
  • Warranty: 7 years
  • Estimated price (Exc. installation): Not available

3. Firebird Envirogreen System C44 internal oil boiler

Firebird Envirogreen System C44 internal oil boiler

The Firebird Envirogreen C44 is the most powerful boiler in its range. It features an acoustic design for ultra-quiet operation and a durable casing with a high-quality finish. It is also equipped with a factory-fitted expansion vessel, circulating pump and a low-pressure switch to protect the boiler in the unlikely event of system water loss.

  • Max. CH output: 44kW
  • Suitable for: Larger properties with 2+ bathrooms
  • Efficiency: 93.8% and ErP A-rated for heat
  • Warranty: 2 years as standard. It can be upgraded to 10 years
  • Estimated price (Exc. installation): £2,180 (Incl. VAT)

Are any of these 42kW system boilers the perfect match for your home? Just click the button below, and we will send you up to 3 offers tailored to your requirements from suppliers in your area. You are not obliged to accept any quote you receive.

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42kW Combi Boilers

Compared to system boilers, combi boilers are much more space-saving heating appliances. They consist of a single unit that can heat your central heating and provide domestic hot water on demand without any additional components (e.g. storage cylinders). Their compactness has made them the most commonly installed type of boiler in the UK.  

Generally, combis are best recommended for small homes and 3-bed houses, as they tend to be less powerful than system and regular boilers. This is also why finding a 42kW combi boiler is somewhat difficult: the number of models available is considerably less than that of less powerful combi boilers (e.g. 25kW or 28kW).

Below, we’ve put together some of the best combi boilers for large houses. We’ve also included estimates for 42kW combi boiler prices. You can compare them to find the ideal 42kW combi boiler for your home:

1. Worcester Bosch Greenstar 8000 LifeStyle 45kW combi gas boiler

Worcester Bosch Greenstar 8000 LifeStyle 45kW combi gas boiler

These are actually two premium Worcester Bosch boilers: Life and Style. They might not be precisely Worcester Bosch 42kW combi boiler units, but these 45kW (DHW) models are the closest output in this reputed brand’s range.

The Greenstar 8000 Life 45kW and the Greenstar 8000 Style 45kW share all the main features, but the Style model is available in high gloss black or white, making it a better choice for interior design. It is also more expensive than the Life version. 

These boilers include wireless connectivity with the Bosch EasyControl. They are also ready to run on a 20% hydrogen blend. Optionally, you can equip them with an Intelligent Filling System. 

  • Max. CH output: 35kW
  • Max. DHW output*: 43.5kW
  • Suitable for: Homes with up to 15 radiators and more than 1 bathroom
  • Efficiency: 94% efficiency and ErP A-rated for heat and hot water
  • Warranty: 5-year warranty as standard. It can be extended to 12 years when installed by a Worcester Bosch accredited installer
  • Estimated price (Exc. installation): Including VAT, the Greenstar 8000 Life 45kW boiler price is £1,800, while the Greenstar 8000 Style 45kW can cost you approximately £1,908

2. Vaillant ecoTEC Exclusive Green IQ 843 combi gas boiler

Vaillant ecoTEC Exclusive Green IQ 843 combi gas boiler

A bit over the 42kW (DHW) threshold, this combi boiler by Vaillant is the first-ever boiler with the power of green IQ technology. It combines a complete range of smart technologies and features to improve efficiency. The ecoTEC Exclusive Green IQ 843 can intelligently manage consumption and output, keeping its components running at peak performance for a longer time.

  • Max. CH output: 36kW
  • Max. DHW output*: 43.4kW
  • Suitable for: Properties with up to 20 radiators
  • Efficiency: 94% efficiency and ErP A-rated for heat and hot water
  • Warranty: 5-year warranty as standard. It can be extended to 7-10 years when installed by a Vaillant Advance installer
  • Estimated price (Exc. installation): £1,673 (Incl. VAT)

3. Ravenheat HE 42 combi gas boiler

Ravenheat HE 42 combi gas boiler

This Ravenheat 42kW (DHW) combi boiler includes a fully modulating burner and fan, a standard neat valve connection, and a low-emissions heat exchanger. It also features compact and colour-coded valves with easy access to all main components.

  • Max. CH output: 35.5kW
  • Max. DHW output*: 41.5kW
  • Suitable for: Larger homes with a higher demand for heating and hot water
  • Efficiency: 90.6% efficiency and ErP A-rated for heat and hot water
  • Warranty: 3 years
  • Estimated price (Exc. installation): £1,444 (Incl. VAT)

* Combi boilers have two output ratings: one for central heating (CH) and another for domestic hot water (DHW).

If you’re interested in purchasing a 42kW combi boiler, and you would like to compare different installers, then GreenMatch is here to help. Just click the button below, and we will send you up to 3 offers tailored to your requirements from suppliers in your area. You are not obliged to accept any quote you receive.

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42kW Heat-Only Boilers

Conventional boilers —also known as regular boilers or heat-only boilers— are among the oldest types of boilers around. These traditional heating systems are suitable mainly for large houses.

They produce hot water for central heating, but not for your taps or showers. To provide hot water for domestic use, a regular boiler needs a large feed water tank in the loft and a hot water storage cylinder. Even though regular boilers may sound a bit old-fashioned, most boiler brands keep manufacturing highly efficient units compatible with modern technologies.

In any case, a conventional boiler will take up considerable space around your home, making the installation process more complicated. This is why regular boilers are not generally recommended if you are not replacing an existing old one.

That being said, if you have enough space to accommodate the regular boiler main unit, the hot water storage cylinder and the feed water tank, check our list of 42kW heat-only boiler models:

1. Worcester Bosch Greenstar FS 42CDi regular gas boiler

Worcester Bosch Greenstar FS 42CDi regular gas boiler

This Worcester Bosch 42kW boiler can be used with Greenskies solar panels for homes, which will help you save energy and cut your household bills. Additionally, it is easy to use thanks to its simple controls, knobs, and temperature display.

  • Max. CH output: 41kW
  • Suitable for: Larger properties with over 20 radiators
  • Efficiency: 92% efficiency and ErP A-rated for heat
  • Warranty: up to 7 years when installed by a Worcester accredited installer
  • Estimated price (Exc. installation): £2,091 (Incl. VAT)

2. Ferroli BLUEHELIX TEC S 45 H heat-only gas boiler

Ferroli BLUEHELIX TEC S 45 H heat-only gas boiler

The Bluehelix TEC S 45 H is a condensing boiler boasting a 98% efficiency rating which could help you lower your heating bills. It features an ECO function that reduces energy usage when delivering hot water.

  • Max. CH output: 45.6kW
  • Suitable for: Homes with over 20 radiators
  • Efficiency: 98% efficiency and ErP A-rated for heat
  • Warranty: 2 years as standard
  • Estimated price (Exc. installation): Not available

3. Firebird Envirogreen Popular C44 Boilerhouse regular oil boiler

Firebird Envirogreen Popular C44 Boilerhouse regular oil boiler

This boiler comes with a patented heat exchanger design, full insulation, and an acoustic design for quiet operation. Additionally, it features multi-directional flue options and a high-performance burner.

  • Max. CH output: 44kW
  • Suitable for: Larger homes with more than one bathroom and high demand for heating
  • Efficiency: 93.8% efficiency and ErP A-rated for heat
  • Warranty: 2 years
  • Estimated price (Exc. installation): £1,900 (Incl. VAT)

As you can see, there are some excellent models in the 42kW boiler range to choose from. When selecting the most suitable one for your house, we strongly recommend contacting certified local installers and comparing their quotes to get accurate indications and also the best value for your money.

We can help you do just that – simply click the button below to receive up to 3 free, non-binding quotes now.

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FAQ

Luis Antonio Gómez Pérez

Luis Antonio is a seasoned Content Writer with international journalism experience. His writing style, enriched by a Master’s in Journalism, contributes informative content to GreenMatch on topics including low-carbon heating systems.

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