Best 40kW combi boiler for 2022

Best 40kW Boiler for 2022
worcester 8000 40kw combi boiler

Combination boilers of 40kW are capable of providing hot water to homes with two bathrooms. You may experience a drop in pressure if you use two showers at once. A system boiler is better than a combi for this, but as boilers improve and technology gets better, a powerful combi boiler can keep up.

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A combi boiler eliminates the need for a traditional cylinder. They heat water as needed and then direct it to the tap. This will save you space. Additionally, you will always have hot water (though you might need to wait until the hot water tank is full).

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Q What kind of fuel does your boiler use?

Best 40kW combi boilers for central heating

You have many choices because all the major boiler manufacturers make powerful 40 kW combi-boilers.

  • Worcester Bosch Greenstar 8000 Life
  • Baxi 800 Platinum+
  • Ideal Vogue Max
  • ATAG i40C

How does a combi boiler work?

Combi boilers heat your home instantly and provide hot water. Check out some of the best combi boilers available right now with a range of different outputs.

The combis are connected directly to the mains water supply. When you turn on a hot tap, the combi heats water from mains and then sends it directly to the tap.

Regular and system boilers do not do this. Instead, they keep hot water in a container. You’ll have to wait for the hot water to return to its full capacity every now and again.

A cylinder has the advantage of being able to meet higher hot water demand. This allows you to have hot water for more than one outlet. It is something that most combi boilers cannot do. You need one that has high domestic hot-water output ratings. A 40kw combi boiler is the best.

Is a 40kW boiler a good choice for my home?

A 40 kW combi boiler produces 40 kilowatts of domestic hot water heating output.

This could mean they might be able to supply hot water for homes with 2 bathrooms.

The boiler’s power is measured by its output rating. Combi boilers have separate output ratings for central heating (CH), and domestic hot water (DHW). This is different from regular boilers that only have a CH output rating. Combi boilers store hot water in a cylindrical.

The central heating output of any combi boiler is not as high as 40kW. All of the top 40kW (DHW), best gas combi boilers heat 15-20 radiators. They do this whilst keeping a high-efficiency energy rating.

It is important to get the right output rating for your boiler. Your heating bills will go up if the boiler is too powerful. If it’s not powerful enough, it won’t be able to meet your heating and hot water needs.

System boilers are the best choice for homes with multiple bathrooms.

I am not certain if a combination of 40kW and 60kW is right for my house…

Don’t worry if you’re not sure. Many heating engineers are available to provide expert advice. You can get a free online fixed price quote in under 20 seconds online now with Boiler Central for boilers suitable for your hot water needs. If you are unsure, you can always give us a quick call and speak to one of our experts right away.

Combi boilers up to 40 kW

You’re lucky if you choose one of our Gas Safe registered engineers who recommend that you install a natural gas 40kW combi-boiler in your home. There are many top-quality models available in this output and they come with great warranties too.

Worcester Bosch Greenstar 8000 Life 40

Worcester Bosch Greenstar 8000 Lifestyle range comprises Life boilers (30-50kw) and style boilers (30-50 kW). Style boilers come in both black and white, while Life units are only available in white. No matter if you have a Style or Life boiler, they share several industry-leading characteristics.

  • High DHW flow rate and output and high erp water heating efficiency
  • Greenstar intelligent filling system
  • Premium gas boiler
  • Hydrogen ready combi boiler
  • Quiet noise level
  • Bosch EasyControl is compatible. You can control the heating and hotwater from your phone.
  • To increase efficiency during operation, use 1:10 modulation

Baxi 800 Platinum Plus

Baxi boilers are well-respected, especially by installers. The Baxi 800 Platinum Plus is ideal for larger homes. It also runs efficiently, helping to lower your energy costs.

  • OpenTherm technology allows for you to control your smartphone or tablet from anywhere.
  • The flow rate is 16.4 litres/minute at a temperature rise of 35degC makes it well-suited to homes that have multiple bathrooms.
  • Frost thermostat with built-in protection against freezing during winter months
  • To offer more flexibility in installation can be fitted with multi-fit flue systems
  • Energy Saving Trust endorses

Ideal Vogue Max

Ideal Boilers are known for making premium products. The Vogue Max range by Ideal Boilers is no exception. Ideal Boilers only uses the highest quality components in this boiler. The warranty can last up to 12 years.

  • Installed by an Ideal Max-accredited gas boiler installer, the warranty can be extended for up to 12 year.
  • Boiler frost protect to keep the unit operating in the coldest conditions
  • Installing a combi boiler that is lightweight can be much easier than hiring an installer.
  • Clear text messages are displayed on the LCD display to explain the issue in the unlikely case of a fault.


ATAG i40C can be a powerful choice for homes with more than one bathroom. The ATAG i40C is also extremely efficient, which will lower your energy bills. You’ll also be covered by a long 10 year warranty. You can also extend this warranty to 14 years with ATAG by following certain guidelines.

  • When used with the ATAG One Zone controller, it achieves an A+ efficiency rating
  • The iCON stainless steel heat exchanger comes with a lifetime replacement guarantee
  • Adjusts flow temperature automatically based on external conditions
  • For those with limited space, compact dimensions of 700x440x355mm (HxWxD), are ideal.
  • High flow rate at 35degC temperature increase of 16.2 litres per hour
  • Energy Saving Trust has endorsed this plan

How much do 40kW combi boilers cost?

Combi boilers are the most economical boiler type. Combi boilers don’t require external tanks or even cylinders therefore a new combi boiler cost around £2,000 on average.

A natural gas 40kW combi could be yours for less than £1,300 before installation costs. Expect full boiler installation prices to be around £2,300

All heating engineers have their own installation prices. They can vary depending upon the boiler type, complexity, and location. Boiler installation in London is the most expensive.

Comparing multiple quotes is a great way to get the best deal for your combi boiler install. Complete our online form to let us know what job you are looking for and we’ll provide you with free quotes by up to three local heating engineers.

The best powerful combi boilers for homes without gas

Many properties are not connected to the gas system. This means that off-grid properties will require a boiler that can run on as an alternative to gas boilers. LPG is an alternative to gas, which can be stored in a local storage tank.

If properties aren’t connected directly to the gas network oil can be used. There are many options to meet your heating and hot water needs, including a 40kW oil combi boiler.

An OFTEC certified heating engineer will be required to install an oil boiler. Our online form allows you to request free quotes for heating engineers in your locality.

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