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Best Combi Boiler 2024 Review and Best UK Boilers to Buy

Which are the best combi boilers in the UK?

worcester 4000 combi boiler

The demand for efficient and cost-effective heating solutions has made combi boilers a popular choice in the UK. Known for their compact size and on-demand hot water supply, combi boilers are a staple in over 80% of UK homes​​.

This article presents a well-researched overview of the best combi boilers available in the UK for 2023, aiding homeowners in making an informed decision for their heating needs.

Get fixed prices online in just 20 seconds – Click here

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So, which combi boiler is best?

Our research, which involved a detailed comparison of numerous models based on factors like power output, price, customer reviews, and water flow rates, has led to a list of top combi boilers, each excelling in specific areas:

At Compare Boiler Quotes, we offer a wide range of combi boilers from a variety of boiler manufacturers and strive to provide our clients with the best combi boiler prices and boiler installation services possible.

Here is our pick for the best combi boiler on the market right now in terms of value for money, performance, and dependability.

Top 5 Best combi boilers to buy right now

RankCombi Boiler
1Viessmann Vitodens 050-w
2Alpha E-TEc 28kw
3Worcester Bosch Greenstar 1000
4Ideal logic C30
5Worcester Bosch Greenstar 8000
6Worcester Bosch Greenstar 4000

Why are they the best combi boilers

  • Best Overall: The Viessmann Vitodens 050-w is German-engineered, it offers reliable performance with a stainless steel heat exchanger. Notable for its efficiency, it’s hydrogen-ready up to 20%​​.
  • Runner-Up: The Alpha E-tec is known for its reliability and ease of use; this boiler is hydrogen blend ready and comes with a 10-year warranty​​.
  • Best Budget Option: The Worcester Bosch Greenstar 1000 is ideal for small to medium-sized homes, offering reduced electricity usage and protection against frost​​.
  • Most Installed in the UK: The Ideal Logic C30 is compact and easy to use, popular among new-build developers, and offers a 10-year warranty​​.
  • Feature-Rich Option: The Worcester Bosch 8000 is known for its power and reliability; it’s future-proof with built-in WiFi and hydrogen blend readiness​​.

#1 Best Combi Boiler – Viessmann Vitodens 050-W best combi boilers guide

Viessmann is well-known for its energy-efficient boiler solutions, and the company has been producing dependable, environmentally friendly boilers and central heating systems for over 100 years.

Today, the brand offers a wide range of innovative solutions, including the Vitodens 050-W wall-mounted gas condensing combi boiler.

Buyers can get a compact boiler with a lot of modern features and that is built to last for a long time for a relatively low price.

viessmann vitodens 050-w combi boiler

The Vitodens 050-W boiler model was designed with quality and dependability in mind, and it shows in every component.

This is one of the best boilers on the market for tech-savvy homeowners who want all of the latest functions for their new boiler, from the stainless steel Inox-Radial heat exchanger to the digital interface with its bold LCD display.

Some of the other benefits of the Viessmann Vitodens 050-W are:

  • The Vitodens 050-W boiler has two DHW output ratings: 5.9 to 30 kW and 8 to 35 kW.
  • The Viessmann Vitodens 050-W is light and compact, weighing only 37 kg and standing 707mm tall, making it ideal for small properties with limited space.
  • As a light, compact boiler, this model is simple to transport and install, even in difficult properties such as a top-floor apartment.
  • The boiler is unobtrusive and quiet.
  • The Vitodens 050-W comes with a 3-year warranty that can be extended to a 7-year warranty.
  • Because the boiler is wall-mounted, it can be discreetly placed in a small recess or nook.
  • Viessmann provides a variety of accessories to complement the Vitodens 050-W, such as a tado° thermostat with a smartphone app and an outside temperature sensor.
  • The brand is well-known and respected for producing high-quality products, so you can be confident that a Viessmann boiler like this one will provide excellent value.

Read more: Viessmann Vitdoens 050 boiler review

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#2 Best Combi Boiler – Alpha E-Tec combi boilerbest combi boilers guide

Alpha has been developing innovative and powerful combi boilers and heating solutions for over 50 years, making the company a relative newcomer to the market.

best combi boiler guide

After all, Alpha has roughly half the experience of some of the other combi boiler manufacturers on this list, but that doesn’t mean the brand isn’t producing high-quality, unique boiler products that can compete with the products of the brand’s more seasoned competitors.

The Alpha E-Tec combi boiler is a favourite of British homeowners and boiler engineers for its style and quality.

This compact boiler is Alpha’s smallest ever, and it was designed with discretion in mind. It has a bright white finish that both looks and functions well.

Other advantages of the Alpha E-Tec combi boiler include:

  • The Alpha E-Tec features a combined condensate and pressure relief valve connection, as well as an advanced stainless steel heat exchanger.
  • It also has a zinc-plated expansion vessel, which is intended to prevent corrosion and extend the life and performance of your new combi boiler.
  • This boiler model is available in two power outputs: 28.3 kW and 32 kW, making it a powerful combi boiler suitable for medium to large homes.
  • As standard, the Alpha E-Tec combi boiler comes with a 7-year warranty.
  • This spotless boiler is small and will look great in most homes.
  • Alpha created the E-Tec combi boiler to be simple to use and maintain.
  • As a result, the parts are easily accessible for inspection or maintenance of the boiler.
  • Furthermore, the digital display and prominent dials on the front are easily visible.
  • As a result of Alpha’s global reputation, homeowners can be confident that they are receiving quality and innovation.

Read more: Alpha E-tec review

When choosing the best combi boilers for central heating and your home, we consider several variables, including your current boiler and the boiler installation process for a new combi boiler in its place.

gas safe combi boiler installation

Once you’ve chosen the type of boiler you want for your home, making decisions is much simpler and you’ll be glad to know that modern combi boilers are the most popular central heating boilers in the UK

If you decide a gas combi boiler is the best for you, you should look for a make and model you like, use our combi boiler reviews to help you decide if it’s right for your home, your central heating system, and also value for money.

#3 Best Combi Boiler – Worcester Bosch Greenstar 1000

The latest addition to the range, the Worcester Bosch 1000, is well and truly a budget biler aimed at landlords and price conscious customers alike.

worcester 1000

The main thing about the Worcester 1000 is that it comes with the best heat exchanger in the whole range, being made from more durable stainless steel rather than aluminium.

It also comes with some of the best features that are available in their mid range and premium boilers such as the Quick Tap feature, and is super quiet too.

Not only is it quiet, making it great for being close to living spaces, but it is also a compact boiler, making it perfect for kitchen cupboards and smaller rental properties.

Why is the Worcester Bosch 1000 a top combi boiler?

Here are some of the main benefits of the Greenstar 1000:

  • Available in 24kw and 30kw output versions to suit more homes
  • Worcester Bosch’s latest budget model
  • Kitchen cupboard fit with dimensions 655mm x 395mm x 285mm
  • Offers a 5-year warranty on parts and labour (7 years when you compare with us)
  • Ultra quiet boiler for the price
  • Smart Worcester Bosch controls compatible
  • Best for small to medium-sized homes with 1 bathroom
  • Reliable stainless steel heat exchanger
  • ErP rating of 94% making it an A-rated energy efficient combi boiler

Why not get a fixed price online now for the Worcester Bosch 1000 combi boiler using our online price tool?

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#4 Best Combi Boiler – Ideal Logic C30

best combi boilers guide

Ideal Heating has a long history of providing some of the best combi boilers on the market, having created boilers for over a century.

Because of its efficiency and quality, the Ideal Logic boiler range is popular among a wide range of homeowners and property developers.

The Ideal Logic C30 is a condensing gas boiler with three outputs: 24kW, 30kW, and 35kW and as a result, this boiler is a versatile option that is suitable for both small and large properties.

Ideal Heating is committed to flexibility, which is why this boiler model comes with a 2-year parts and labour warranty, as well as a 10-year warranty on the heat exchanger.

Some of the other benefits of the Ideal Logic C30 combi boiler are:

ideal logic combi boiler
  • The Ideal Logic C30 has a class A rating for both water heating energy efficiency and seasonal space heating efficiency, making it ideal for environmentally conscious homeowners.
  • Over the course of its life, an energy-efficient boiler like this one will save you money on your energy bills.
  • The boiler is small and has a maximum installed weight of only 29.0 Kg, making it ideal for installation in a small cupboard.
  • The boiler from Ideal Logic features an innovative, backlit digital display.
  • The pressure gauge is visible, making the boiler simple to maintain and inspect.
  • It also has frost protection, which is ideal for British winters because it prevents the boiler and its pipework from freezing during the colder months.
  • The Ideal Logic C30 can be converted to LPG fuel by homeowners using Ideal Heating’s conversion kit.
  • This model can connect to a maximum of an 8m horizontal flue and a 7.5m vertical flue, making it suitable for a wide range of properties.
  • Aside from the standard features of the Ideal Logic C30, Ideal Heating also offers optional accessories for this model, such as a weather compensation kit and a radio frequency programmable digital thermostat.
  • Ideal Heating has been manufacturing boilers for over 100 years, so you can be confident that this is a high-quality product.

Read more: Ideal Logic C30 review

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5th Best Combi Boiler – Worcester Bosch 8000 LifeStyle

The 8000 Life And Style, another high-quality product from the renowned boiler brand Worcester Bosch, is a replacement for the beloved Worcester Bosch Greenstar CDi Classic.

This new Worcester Bosch boiler retains all of the features of the Greenstar CDi Classic while also being a modern update, which means that the new model will provide homeowners with the same, if not more, comfort and satisfaction than its predecessor.

best combi boiler guide

As previously stated, Worcester Bosch is a well-known manufacturer of high-quality boilers, so it’s no surprise that two of the brand’s products appear on this list of the best combi boiler options.

Life and Style 8000. This is available as a combi boiler as well as a system boiler. The combi version has power outputs ranging from 30kW to 50kW, making it a powerful boiler suitable for larger properties with high hot water demands.

Other advantages of the 8000 Life and Style include:

  • The 8000 Life and Style is a wall-mounted gas combi boiler that will look great in any home.
  • The boiler’s sleek, black design distinguishes it from others and will look great on any property.
  • This Worchester Bosch boiler is also available in white, allowing you to select the style that best suits your preferences.
  • The boiler, which is part of the Greenstar line, is efficient and has cutting-edge features.
  • Among these novel features is a backlit digital display.
  • Despite its size, the boiler is quiet and unobtrusive.
  • This contemporary design is easily connected to smart heating controls, making it an excellent choice for tech-savvy homeowners.
  • It can also be used with the Bosch wireless EasyControl app, allowing owners to control the temperature in their home from a smartphone or tablet.
  • This is one of the most powerful combi boilers available, making it ideal for larger homes with greater hot water and heating demands.
  • For your peace of mind, the boiler comes with a 12-year warranty.
  • While the 8000 Life and Style is one of the most expensive models on this list, it has a slew of extra style features and functions that make it worthwhile for modern homeowners with large properties looking for a combi boiler.

Read more: Worcester Bosch 8000 Review

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Get your combi boiler quotes here

6th Best Combi Boiler – Worcester Bosch Greenstar 4000

Part of Worcester Bosch’s renowned Greenstar combi boiler range, the Greenstar 4000 is an energy-efficient combi boiler.

worcester 4000

Worcester Bosch is one of the world’s most reputable combi boiler manufacturers, with a long history of producing high-quality products that are popular among homeowners and professional heating engineers.

Since its humble beginnings in 1962, the company has thrived, eventually joining the globally respected Bosch Group in 1996.

Worcester Bosch combi boilers are renowned for their efficiency and longevity, and the brand is now one of the most respected in boiler technology.

The Worcester Bosch Greenstar range is one of its most popular combi boiler options.

The Greenstar 4000 combi boiler exemplifies the brand’s dedication to quality and innovation and the superiority of this popular collection.

This compact Worcester Bosch combi boiler with a 25kW or 30kW combi boiler output is reasonably priced and designed for convenience.

As a result, it has removable side panels, allowing installers and boiler engineers easy access to the PRV and other internal machinery.

Some of the other benefits of the Worcester Bosch Greenstar 4000 combi boiler are:

  • The Greenstar 4000 comes with a 10-year warranty, so you can be confident that if something goes wrong in the first decade, the brand will cover it.
  • The product features Worcester Bosch’s innovative C6 Heat Exchanger, which can modulate down to 4.8kW, improving the boiler’s energy efficiency.
  • The boiler can be attached to a flue up to 9m horizontally and 12m vertically, making it suitable for a wide range of properties.
  • The Worcester Bosch Greenstar 4000’s quick tap feature allows homeowners to save water and energy while also getting hot water quickly.
  • This model is one of the brand’s quietest options, so it will not bother your family.
  • The Greenstar 4000 works perfectly with 230V heating controls.
  • The boiler is easy to access and maintain, with most parts removable in seconds.
  • It has a replaceable main cable to increase longevity and make future maintenance even easier.
  • The Worcester Bosch Greenstar 4000, manufactured by a reputable boiler manufacturer, is dependable and will provide you with excellent service for more than a decade.
  • All of these cutting-edge features and functions are reasonably priced.

Read more: Worcester Bosch 4000 combi boiler review or if you want a cheaper boiler but a Worcester check out our Worcester 2000 boiler review

How to get the best combi boiler for your home

Once you’ve determined that combi boilers are the best solution for you, you must determine what is appropriate for your home.

You’ve already learned about the best boiler brands and their entire product line, so now we’ll show you the top 5 combi boilers on the market right now so before you continue reading, keep in mind that the best place to buy your new boiler (with industry-leading warranties) is right here at Boiler Central.

best combi boilers guide

Searching through all of the available brands on the market can be time-consuming and stressful, which is why we’ve put together this guide to the best combi boilers for sale.

How to get the most energy efficient combi boiler

Choosing the most energy efficient combi boiler to suit your home is so important. There are many combi boiler brands that offer a wide range of gas boilers in varying different shapes and outputs, so you must decide which boilers are the best on the market and which are best for your home.

Even if you are certain you want a combi boiler, there are many other things to consider when choosing a new boiler replacement.

To find the best combi boiler that will give you the highest return on your initial investment, you must consider a number of factors, including the power output and the material of the heat exchanger.

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Top combi boiler models in the UK

The top combi boilers can only be found in this guide and to ensure we have the right models we have ensured that we looked in every corner.

To find the best combi boiler models right now, we consider the following factors, which provide concrete evidence in finding the best gas combi boilers on the market:

  • Is it a reliable boiler?
  • Is it an energy efficient combi boiler?
  • The manufacturer’s Trustpilot rating
  • Market reputation of the brand
  • Are there any awards, such as Which? Best Purchase
  • How long does the warranty last?
  • Price range in comparison to competing combi boiler brands
  • Brand customer service and aftercare
  • Hot water flow rate

All the top models in our list are some of the most energy-efficient combi boilers that not only keep your heating bills down and lower your carbon footprint but are reliable combi boilers that will also save you money on repairs and maintenance over the years to come.

#1 Viessmann

Viessmann is a German brand that has gained a significant market share in the last 4 to 5 years thanks to some fantastic boilers for all budgets. They also make the most reliable combi boiler in the form of the Vitodens 100-w which has been given a reliability rating of 98.5%!

viessmann combi boilers logo

There is a boiler for every home in their range, from low-end workhorses to high-end storage combi boilers like the Viessmann 111-W. Moreover, they provide new boiler options based on German engineering.

The full range of Viessmann models and the best combi boiler options right now are listed below, in order of best to worst.

Why are Viessmann the best combi boilers?

Viessmann manufactures cutting-edge boilers, as one would expect from such a renowned boiler manufacturer, hence why we think they make the best combi boilers.

stainless steel heat exchanger in combi boiler

Viessmann manufactures the most popular and most efficient combi boilers in the UK, with no cylinders or water tanks and instant hot water and heating for your radiators. It represents the pinnacle of heating and hot water technology.

Here are some of the most compelling reasons to purchase a Viessmann boiler:

  • Plastic components are not used in any of Viessmann’s boilers.
  • Stainless steel heat exchanger as opposed to aluminium
  • The pressure relief pipe and condensate are merged throughout the Viessmann boiler series.
  • Viessmann has accomplished the unusual job of fitting all of their award-winning, ecologically friendly magic into remarkably compact case sizes.

Worcester Bosch includes plastic parts and uses an aluminium heat exchanger.

Viessmann has accomplished the unusual job of fitting all of their award-winning, ecologically friendly magic into remarkably compact case sizes.

Viessmann has remained a true force in the UK for too long and is currently on a crusade to offer high-quality German boilers to the UK domestic market. 

They are also now offering their impressive gas boilers at low prices to appeal to the masses.

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What does Viessmann have that others don’t?

  • The Industry’s Best Heat Exchanger
    • Heat Exchanger comes with a limited lifetime warranty. Almost all other boiler manufacturers provide warranties of fewer than ten years. Why? Because their heat exchanger fails before the age of ten years.
  • Installation is simple and quick.
    • NPT pipe connections are conveniently located at the bottom.
    • Control Wiring Made Simple
    • Controls are simple.
  • Viessmann’s very own Matrix Burner
    • High efficiency and ultra-low emissions
    • Stainless steel structure for long-term dependability
    • Viessmann designed and produced in
  • Viessmann is the world’s leading expert in boilers.
    • Located in Germany Viessmann is a genuine boiler producer. Viessmann develops, engineers, and manufactures everything that goes into its products, allowing them to have better control over the quality and lifetime of its goods.
    • Viessmann is a leading manufacturer of heating and renewable energy solutions around the globe.
    • The Vitdoens 100-w is the most efficient combi boiler

Read our Viessmann 050-W review for more information on this excellent combi boiler.

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Viessmann Vitodens 100-W combi boiler

viessmann vitodens 100-w combi boiler

In our opinion, the Viessmann Vitodens 100-W combi boiler is the second-best boiler in the Viessmann lineup, and it’s a step up from the Viessmann 050-W we looked at earlier because it has higher-grade internal components. This is the most reliable combi boiler in the UK and the Vitodens 100-W has the following advantages:

  • A ten-year warranty (12 years with Boiler Central)
  • The boiler is controlled via an LCD display
  • Heat exchanger made of stainless steel
  • Very quiet boiler
  • Updated in 2021 and looks fantastic (aesthetics only)
  • A-rated and emits low levels of pollution

Many providers offer a 10-year warranty, but WHY settle for less? When Boiler Central offer a whopping 12-year warranty?

Using this calculator, you can get a fixed price

vissmann vitodens 111-w storage combi boiler

If you’re worried that a combi boiler won’t be enough for your home, reconsider. The Viessmann Vitodens 111-W answers most large homes’ hot water and heating needs.

Get a fixed price here in 20 seconds

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#2 Worcester Bosch

worcester bosch logo

Worcester Bosch is well-known for its excellent range of combi boilers and is one of the best combi boiler brands in the UK

They recently revamped their combi range, offering budget, mid, and high-end boilers.

Including a variety of Which? Best Buy awards where come out on top every year. Because they are based in the United Kingdom, it is no surprise that they provide one of the highest quality combi boilers at various price points.

Why is Worcester Bosch regarded as one of the best?

Simply put, we give ratings based on the criteria listed above, and Worcester comes out on top. The following are some of the best features:

  • Long 10-year warranties are available (12-year if you purchase here at Boiler Central)
  • Customers rate aftercare as the best.
  • Trustpilot and other review sites rate them highly.
  • Quality products are manufactured in the United Kingdom.
  • Boilers that are suitable for the majority of homes.

You can get a Worcester Bosch combi boiler installed in your home tomorrow simply by getting a quote online now.

Get a fixed price here

Worcester Bosch Greenstar 4000 combi boiler

worceter 4000 combi boiler quiet mark

The Worcester Bosch Greenstar 4000 range, which is a mid-range combi boiler that replaces the Greenstar I was introduced in 2021 and is found in a large proportion of UK homes and if you want more information, we recently completed an in-depth Worcester 4000 review.

These fantastic Worcester Bosch combi boilers are sleek in appearance, a well-rounded boiler has been proven to last a long time, and furthermore, they provide a long warranty with this 4000 range to give you peace of mind. If something goes wrong, the warranty covers parts, labour, and call-outs.

This range has wireless connectivity and can be used with smart thermostats like the Google Nest or Hive.

Read more: Best smart thermostat guide

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worceter bosch greenstar i

Despite the fact that British Gas boiler prices are much higher than those of online boiler companies, the company still produces a large number of Worcester combi boilers.

There are over 1 million Greenstar I boilers installed in homes in the UK, which explains why they were the number one and most installed boiler for over a decade.

Like having powerful showers? Read our guide on the combi boiler with high efficiency and flow rate.

worcester bosch 8000 combi boiler

The 8000 style and life boilers are available in kilowatt (kW) ratings ranging from 30kW to 50kW – A 50kW combi boiler is enormous and has serious power for large homes, such as these boilers for five-bedroom houses.

It has many of the same advantages as the Worcester 4000, such as smart connectivity, an intelligent filling system and pressure monitors, curved edges, and an extremely user-friendly touchscreen display.

`Read more: Worcester 8000 Life and Style boiler review

Simply put, they offer the best boiler ranges because their brand is so well-known, with an array of benefits that outweigh their competitors.

Do you want to know how much a new boiler costs from Worcester? Get a fixed price on the best boiler by filling out the form below:

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#3 Ideal Heating

ideal combi boilers logo

Ideal is a well-known UK boiler manufacturer that has significantly improved in recent years, and in addition to being the UK’s most installed boilers, the boiler range and marketing campaigns have seen a significant increase.

They are installed in a high percentage of new build homes (clearly won the tender), and new home buyers have no complaints about these dependable Ideal combi boilers.

Read our Ideal boiler price guide for full pricing and information on an Ideal boiler replacement cost.

These are the best combi boilers from Ideal

Ideal Logic combi boiler

The Ideal Logic range is ideal for many homes, with a whopping 10-year guarantee when purchased from heating giants such as Boiler Central. This combi boiler cost less than the others in our line up and is the most installed combi boiler in the UK

ideal logic combi boiler

This range of combi boilers has many advantages and will last for years without any hassle or fuss. Some of the best features of these hybrids include:

  • Made in the United Kingdom with high-quality components
  • There is a 10-year warranty available (at Boiler Central)
  • Small and compact for kitchen cabinetry
  • Has a Quiet Mark certification (super quiet)
  • In 2013 and 2017, she received the Good Housekeeping Award.
  • Trustpilot gave us an excellent rating.

If you are looking to compare prices on an Ideal boiler, click here now

Ideal Vogue & Vogue Max

The Ideal Vogue is a combi boiler aimed at the mid to high-end market, as these are at the higher end of the price range for a new boiler replacement for your home consequently, with sizes ranging from 26kW to a whopping 40kW, they have a solution for small, medium, and large properties.

They have the Vogue and Vogue Max collections. The main distinction is that the Vogue Max includes an Ideal-approved and manufactured water filter, which results in a longer warranty.

They increase the warranty for the Vogue Max from 10 to 12 years and truly provide a great combi boiler for any property.

Model and size-dependent prices range from £2,200 to £2,900.

Get a price on any of the above Ideal boilers with our free online tool here.

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#4 Best combi boilers – Alpha

alpha combi boiler logo

Alpha is a fairly new name to the boiler industry and provides a range of low to mid-range boilers. They offer both affordable and reliable boilers and these top combi boilers cost less than most on the market.

In the range they have various combi and boiler types to choose from, of which the best of these are outlined below:

Alpha E-Tec

The Alpha E-Tec combi boiler is a budget buy that packs a punch in terms of reliability and performance for the price range as Alpha boiler prices are generally low, you can pick the 29kW up from Boiler Central for £1,595 fully fitted and installed with a huge 10-year warranty.

Something to note is their Excellent Trustpilot reviews. If they were not a really good combi boiler then Alpha’s Trustpilot would let us know for sure.

The E-Tec is available in a 29kw 33kW and 38kW power range which perfectly suits small, mid and larger properties alike, therefore, they really do have a kilowatt rating boiler suitable for most homes that require a combi.

Features and benefits of the E-Tec are below:

alpha etec combi boiler
  • 7-year warranty (10-years with Boiler Central)
  • Stainless steel heat exchangers
  • Easy access to the pipes for servicing
  • Can deliver a huge 14.1 litres per minute
  • Ideal for small and medium-size homes
  • Can be used with smart thermostats

If anything more than 38kW is required, and a combi boiler is needed, then the Worcester Bosch 8000 boiler is probably the way to go.

We think that the best in their range is probably the E-Tec plus so if you’re set on an Alpha, then get that one. You can get a price on one of them here.

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#5 Best combi boilers – Vaillant

vaillant combi boilers logo

Vaillant is a well-known brand of boilers that are always bubbling around the 4-5th spots as they do not seem to be able to produce boilers like Worcester Bosch and Viessmann.

Although Vaillant combi boilers are actually manufactured in the UK, most customers think they are a foreign boiler company, they have decent warranties and their ecoTEC range is certainly their most popular.

Perhaps they need a wider price range because they have so many boilers in their lineup, so if you need more information on Vaillant boiler prices, our guide will assist you in determining what is best for you.

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What is a combi boiler?

Before we get into our list of the best boilers on the market right now, we thought we’d define a combi boiler so you know exactly what you’re getting.

A combination boiler, also known as a combi boiler, is a small unit that efficiently provides hot water on demand for your home’s heating and taps. It uses cold water direct from the mains, heats it up internally and distributes red hot water to taps and radiators.

What makes combination boilers so good?

best combi boiler (internal)

Because a combi boiler heats water on demand for your taps and central heating, you only need one unit.

Because this type of boiler heats water as needed, it does not require bulky additional equipment like a cold water tank or a hot water storage cylinder.

Changing to a combi boiler is one of the most popular ways to increase energy efficiency in a small to medium-sized home that has a conventional boiler with a hot water tank.

As a result, these boilers are compact and can be easily tucked into an airing cupboard or a tight recess. Combi boilers are one of the best options for homeowners who want to save money on their energy bills while also reducing their environmental impact.

The disadvantage of combi boilers is that, due to their small size, they are unable to meet high hot water demand, as a result, they are ideal for small properties with few bedrooms and bathrooms, such as flats, bungalows, and small houses.

Combi boilers are ideal for these properties because they are cost-effective in terms of both purchasing and installing the boiler as well as running it.

Sounds great, but they aren’t always the best choice for every home.

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Alternatives to a combi boiler?

A combi boiler may not be the best boiler for your lifestyle for some homeowners as they may not be the best choice if you have a large home with multiple bedrooms or if you already have a different type of boiler.

Combi boilers are currently among the most popular types of boilers on the market, but they are not the only ones.

System boilers

system boiler hot water tank

A system boiler is a solution that stores hot water in a hot water cylinder until it is needed for your home’s central heating system or to supply hot water to the taps.

As a result, system boilers including a tank take up more space and are slightly larger than combi boilers, but they are also more powerful and can accommodate larger homes.

Regular boilers

Regular, or heat-only, boilers are another popular option. These boilers necessitate the purchase of additional equipment, including not only the unit and the hot water cylinder but also a cold water tank and a hot water storage tank.

best combi boilers guide

All of these components combine to form a powerful system capable of meeting the needs of large properties such as small commercial premises or large family homes with many people.

Combi boilers are the most cost-effective option, but if you require a more powerful solution, one of these boilers may be the best option.

Many systems and standard boilers are designed with energy efficiency in mind, so you can find an energy-efficient option that will save you money on energy bills while also benefiting the environment.

Before you decide on the type of boiler you want, you should learn more about the different types of boilers available.

Using this information, you can find the best boilers to meet your needs and provide you with excellent service for many years.

Read more: Condensing boiler vs combi boiler guide

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How much do the best combi boilers cost?

The best combi boilers cost between £500 and £3,000 depending on the make and model you choose. All the boilers in our review are currently available to buy online from merchants. However, this will not include the combi boiler installation which is often the largest cost.

How much does combi boiler installation cost?

Buying a new combi boiler is all good and well. However, the actual cost of installing a combi boiler is often what makes the buying of a boiler more expensive. The average combi boiler installation cost in the UK is around £2,200 for a mid range model.

Which is the best combi boiler for a 2 bedroom home

A small property with only two bedrooms requires a small combi boiler, so choose a combi with a power output of 20 to 27 kW.

The most suitable boiler for a small flat, apartment, or house is

If you have a small home, check out our small boilers review for more information on the best type to buy and if they will fit in tight spaces such as a kitchen cupboard!

Get a fixed price here

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Which is the best combi boiler for a 3-bedroom home?

Boilers for homes with three bedrooms and higher hot water and heating demands may benefit from a more powerful boiler.

Typically, a combi boiler with a capacity of 28 to 35 kW could benefit the average home of this size.

The best combi boiler model for a two or three-bedroom house is:

Get a price here.

Which is the best combi boiler for a 4 bedroom home?

A combi boiler for a house with four bedrooms is over 35kw and the most common size for which a combi boiler is recommended.

A powerful combi boiler with 36 kW or higher is required for a 4-bedroom home with higher hot water demands and more radiators.

The best boiler model for a three to four-bedroom house is the Worcester Bosch 8000

Are combi boilers more efficient than other types of boilers?

Combi boilers are usually more efficient than regular boilers and system boilers due to them not having a water tank for storage. System and regular boilers will have to heat the water stored in the cylinder, meaning heat and energy are lost when this is cooled down and heated up. 

As the hot water is produced on demand, so there is very little water and energy waste in comparison and choosing the most efficient combi boiler shouldn’t be too hard as there is such a wide range to choose from.

Is it cheaper to run a combi boiler?

The lack of wasted energy and heat when a combi boiler operates also means it is cheaper to use than alternative boiler types.

You get hot water when you want it and there is no excess of it meaning less money is being spent on your boiler working overtime. 

Rather than having a storage tank, combi boilers get their supply straight from the mains, so it is only heated when needed. 

How long before I replace my combi boiler?

A combi boiler should last around 10-15 years, especially modern boilers with better technology so their efficiency will last longer. You can also make a combi boiler last longer by getting annual boiler service as Gas-Safe engineers will be able to examine and maintain your boiler for it to last.

If you notice your boiler has become less efficient when attempting to use hot water and it is within this age range, this is likely a sign that you need a replacement boiler.

Even with boiler service, boilers will become less effective over time and will eventually require replacement to meet your demands and help you save long-term money.

Still unsure what combi boiler is best for you?

If you’re still unsure about which brand, model, and size of combi boiler is best for your home, consult a Gas Safe registered heating engineer.

Compare Boiler Quotes works with boiler experts and Gas Safe installers who can help you find the best new combi boiler for your home and lifestyle, if your looking for something completely different, then check out our Navien boiler review, in which we discuss their claim that they are the best combi boilers in the world.

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Best boilers – Our verdict:

Selecting the best boiler for your home can be challenging because there are so many options available and every boiler manufacturer says they have the best boilers.

best combi boilers guide

So that you can make an informed decision, we can include the cost of a Gas Safe registered engineer installing your boiler. An installer can be scheduled to install your boiler on a day that works for you.

You can choose the best combi boiler for your home and budget by consulting the combi boiler installation costs and boiler prices in front of you.

You’ll probably be able to find your ideal new boiler and the lowest boiler price when you shop with Compare Boiler Quotes.

Additionally, we have some fantastic boiler finance offers that you can use to spread out the cost of your boiler and make monthly payments.

If you’re still unsure which combi boiler will be best for your home, get new boiler quotes in 20 seconds from nationwide boiler companies below:

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