Best Combi Boiler 2024: Top 7 Gas Combi Boilers Review

Looking for the best combi boiler to install in your home this year?

Combination boilers, to give them their full name, are the most popular type of boiler installation in the UK.

Therefore, our comprehensive review cuts to the chase, showcasing the top contenders known for their efficiency, value, low combi boiler installation costs and technological advancements.

Discover which of the best combi boilers our heating engineers prefer which provide the performance to meet your home’s heating and hot water demands without compromising on cost or quality.

Top 7 Best Combi Boiler Review Key Points

• Viessmann and Worcester Bosch are leaders in the UK market for modern combi boilers, offering high efficiency and reliability, with models like Viessmann Vitodens 050-W and Worcester 2000 being praised for their performance and value.
• Selecting the right combi boiler involves considering home heating needs based on radiator count, ensuring energy efficiency to minimise costs and environmental impact, and balancing the upfront price against long-term savings from warranties.
• Key features to consider in the best combi boiler include a compact design for space-saving, smart controls for convenience and energy management, and high energy efficiency to reduce bills and environmental footprint, as seen in the Viessmann Vitodens and Worcester Bosch Greenstar models.

Choosing the Best Gas Combi Boilers for Your Home

When the chill of winter bites, a reliable combi boiler is your best defence.

In 2024, the leaders in the boiler market, including top boiler manufacturers, continue to innovate, providing homeowners with options that are not just efficient but also integrate seamlessly with modern living.

Renowned brands like Viessmann and Worcester Bosch have secured top positions in the UK market, underlined by their commitment to delivering high-efficiency and reliable products, making them some of the best combi boilers available.

If you’re considering an upgrade, a new combi boiler might be the perfect solution for your home heating needs to keep boiler installation costs down.

Top Combi Boiler Models Reviewed

Having covered the basics, we will now examine in detail some of the best combi boiler models available in the market in 2024.

To do this, we focused on key areas that matter to you the most. Therefore, these latest new combi boiler models have been chosen for their:

• Performance
• Price
• Warranty
• Ease of Gas Safe installation
• Central heating output

Other factors to consider are the domestic hot water output you require personally and the size of your central heating system; these are all critical factors in the decision-making process.

From the innovative Worcester Bosch Greenstar 4000 to the efficient Viessmann Vitodens 050-W, each model offers a unique set of features to cater to different needs.

#1 Viessmann Vitodens 050-w

• Best combi boiler for: Everything – Value, reliability, performance and efficiency

The Viessmann Vitodens 050-W is a compact powerhouse, fitting for smaller homes and flats. Its quiet operation, low weight, and A-rated energy efficient combi boiler make it an appealing option.

These top combi boilers also features an easy-to-use LED display and touch buttons, along with web-enabled service capabilities for modern convenience.

Vitodens 050-w Features

• Price: From £2,395
• Boiler Type: Gas Combi Boiler
• Which Recommended?: Yes
• Boiler Warranty: 10-year Viessmann warranty (12 with Boiler Central)
• Output: 3.2kw to 32kw
• Energy Rating: A-Rated
• Instant Hot Water: Yes
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes
• Compact Design: Yes

Read more – Vitodens 050-w full review

#2 Worcester Bosch Greenstar 4000

• Best combi boiler for: Worcester Greenstar range fans

The Worcester Bosch Greenstar 4000 has built a reputation for reliability and operates quietly receiving the Quiet Mark accreditation. Additionally, it comes with a substantial 10-year warranty (12 years at Boiler Central exclusively)

With a modulation ratio of 1:10, it ensures efficient operation by adjusting its output to match the heat demand. Available in 25kW and 30kW power outputs, it’s versatile enough to cater to different home sizes.

Worcester Bosch Greenstar 4000 Features

• Price: From £2,590
• Boiler Type: Gas Combi Boiler

• Which Recommended?: Has Which? Best Buy status
• Boiler Warranty: 10-year warranty (12 years with Boiler Central)*
• Output: 30kW
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Worcester 4000 full review

#3 Viessmann Vitodens 100-W

• Best combi boiler for: Reliability and efficiency

The Viessmann Vitodens 100-W is an affordable yet powerful A rated combi boiler choice for medium-sized homes. It boasts high-end internal parts and a user-friendly backlit LCD Touchscreen.

With a 94% fuel-to-heat conversion rate, it’s both environmentally friendly and efficient.

This model also offers a very high boiler modulation ratio, further reducing energy bills.

Vitodens 100-w features

• Price: From £2,790
• Boiler Type: Gas Combi Boiler
• Built-In Wifi: Yes
• Which Recommended?: Yes in 2021
• Boiler Warranty: 12-year warranty (14 years with Boiler Central)
• Output: 30kw
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Vitodens 100-w full review

#4 Alpha E Tec NX

• Best combi boiler for: Landlords & tight budgets

Alpha’s E Tec NX offers an excellent balance between affordability and quality.

It features a reliable stainless-steel heat exchanger for longevity and operates efficiently in various climates.

This combi boiler is lightweight because it uses a special design that combines metal and plastic. It has an advanced Grudfos pump that adjusts its speed to save energy.

You can set the E-tec’s temperature to make it more efficient and tailor its performance to your home’s needs.

Its energy efficiency ratings ensure that it’s not only cost-effective upfront but also in terms of long-term energy savings.

E-Tec NX features

• Price: From £1,950
• Boiler Type: Gas Combi Boiler
• Boiler Warranty: 10-year warranty (12 years with Boiler Central)*
• Output: 28kW
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Alpha E-tec Combi boiler full review

#5 Worcester Bosch Greenstar 2000

• Best combi boiler for: Top brand on a budget

With the Worcester Bosch Greenstar 2000 affordability meets innovation in a design that’s crafted to blend seamlessly into the background of your kitchen or utility room.

It operates at a whisper-quiet 47 decibels and comes with a 7-year guarantee.

Featuring QuickTap technology, it also boasts environmentally friendly packaging that aligns with today’s green standards.

The 10-year guarantee on the primary heat exchanger underscores Worcester Bosch’s confidence in its design and durability.

Worcester 2000 features

• Price: From £2,385
• Boiler Type: Gas Combi Boiler
• Which Recommended?: Yes
• Boiler Warranty: 6-year warranty (8 with Boiler Central only)
• Output: 30kw
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Worcester 2000 full review

#6 Ideal Logic+ C30

• Best for combi boiler for: Use in tight spaces

The Ideal Logic+ stands as a beacon of economic heating solutions. With its competitive pricing and versatile design, it’s a practical option for a wide range of homeowners.

The Logic+ models are compatible with smart controls, enhancing their user-friendliness and allowing for efficient management of heating.

The A-rated energy efficiency and Quiet Mark accreditation further reinforce its status as a top-performing boiler in the market.

Logic C30 features

• Price: From £2,450
• Boiler Type: Gas Combi Boiler
• Which Recommended?: No
• Boiler Warranty: 10-year warranty
• Output: 30kw
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Ideal Logic combi boiler full review

#7 Vaillant EcoTec Pro

• Best combi boiler for: Use with Heat Pumps

The Vaillant EcoTec Pro series is tailored to fit various domestic settings, offering models like the Pro 24, Pro 28, and Pro 30 to match different hot water demands and be recognised with a Which? Best Buy award, the EcoTec Pro series brings a level of consumer trust that is well-deserved.

Compatible with the AROtherm heat pump, this boiler is the ideal hybrid combi boiler.

These boilers are not only efficient but also come with user-friendly features and smart thermostat compatibility, ensuring ease of use and control.

With a 10-year warranty and a starting installation cost that’s competitive, the Vaillant EcoTec Pro series stands as a cost-effective choice for consumers looking for long-term reliability.

ecoTEc Pro features

• Price: From £2,890
• Boiler Type: Gas Combi Boiler
• Which Recommended?: Yes
• Boiler Warranty: 7-year warranty
• Output: 30kw
• Energy Rating: A-Rated
• Boiler Controls: Wireless heating controls
• Smart Thermostat Compatible: Yes

Read more – Vaillant ecoTEC pro review

Why are people buying these combi boilers?

In the UK, the demand for the best combi boilers is shaped by a preference for energy efficiency and environmental sustainability.

Consumers are increasingly choosing A-rated combi boilers that are not only efficient but also offer smart home compatibility for enhanced energy management.

Brands like Viessmann and Worcester Bosch are popular due to their high-performance boilers capable of serving both small and large homes efficiently.

The new trend is also moving towards hybrid systems that integrate traditional boilers with renewable technologies like solar panels or heat pumps, appealing to eco-conscious consumers looking to future-proof their homes.

These trends reflect a broader shift towards innovative heating solutions that prioritize both energy efficiency and environmental stewardship.

Top Combi Boiler Brands of 2024

There are an abundance of options available, allowing us to delve into the top-tier of best combi boilers, with each brand offering its unique strengths in the best combi brands category.

Lets take a look at the best boiler brands currently available in the UK right now and what they offer along the way.

Viessmann

Viessmann’s best combi boilers are a testament to German engineering excellence.

With a strong brand presence and leading boiler manufacturer in the European boiler market, these boilers are more than 90% efficient and boast an A-rated energy performance.

The Vitodens 050-W is a sterling example and, in our expert opinion, the best combi boiler on the market, with its stainless steel heat exchanger and high water flow rate.

The product has been recognised as the Which? Best Buy award winner, reflecting its outstanding quality and value for the price.

For those seeking extended warranty and versatile size options, The Viessmann Vitodens 100-w and the Vitodens 200-W gas combi boiler stand out as the most efficient combi boilers and the Vitodens 111-w storage combi boiler is an alternative to a system boiler.

Worcester Bosch

Worcester Bosch’s reputation for quality is unrivalled, as evidenced by winning the Which? Best Buy Award for 14 consecutive years.

The Worcester Bosch Greenstar 8000, Greenstar Si Compact and CDi Compact models exemplify the brand’s excellence with features like compact size and frost protection.

The Worcester 2000 model is the embodiment of the brand’s mission to offer quality at a budget-friendly price point.

Ideal

Ideal Boilers shines in the realm of affordability and versatility. With warranties that can extend up to a decade and boilers that cater to a variety of home sizes, Ideal stands as a popular choice among consumers.

The Logic Combi 30, in particular, has garnered accolades such as The Queens Award and The Good Housekeeping Award for its reliability.

Moreover, the Vogue Max Combi Boiler’s Quiet Mark Certification ensures your peace and quiet won’t be disturbed.

Alpha Heating

Alpha Heating strikes a perfect balance with its E-Tec NX combi boilers, offering:

• A-Class efficiency
• Budget-friendly price
• Extended warranties
• Features like integrated filling loops

Alpha Heating’s commitment to customer satisfaction is clear.

The Italian design and manufacturing of these gas boilers ensure a level of European engineering quality that is well-suited for various property types, despite their compact size.

Vaillant

Vaillant stands as a premium brand within the boiler market, with a history of awards including a Which? Best Buy Award.

Their combi boilers, like the ecoTEC exclusive, offer high hot water delivery rates and come with convenient app controls for ease of use.

The ecoTEC plus storage combi boiler model pushes the boundaries of performance with an impressive delivery rate of up to 20 litres per minute.

Choosing the Right Combi Boiler for Your Home

Selecting the perfect combi boiler for your home is like finding the perfect pair of shoes – it all comes down to the right fit.

The choice goes beyond just the boiler’s size or cost; it should also meet your home’s specific heating and hot water needs. You can read about the benefits of a combi boiler here.

The vast array of options in the market can make the process daunting, but rest assured, we’re here to navigate you through the critical considerations, leading you to the combi boiler that best fits your home.

Assessing Your Home’s Heating Needs

Understanding your home’s heating needs begins with the basics: the number of radiators.

This simple count can provide a rough estimate of the power required to be able to get the right size KW boiler to keep your home snug and warm. The boiler’s output, measured in kilowatts (kW), is directly linked to its ability to heat your home effectively.

The goal isn’t to find the biggest or most potent boiler, but to locate the one that aligns with your home’s size and heating necessities.

If you like a powerful shower, read our guide on showers and combi boilers here to get the right output.

Understanding Boiler Efficiency

Boiler efficiency is a critical factor, not only for your comfort but also for your wallet. It’s all about how well your boiler converts fuel into heat.

Combi boilers are among the most efficient options available, minimising energy waste and your environmental footprint.

Brands like Viessmann and Worcester Bosch are known for their efficient boilers, which contribute to long-term savings.

Keep in mind that boiler modulation aids in maintaining a constant temperature while conserving energy, leading to further savings on your bills.

Boiler Plus for Combi boilers

The UK’s Boiler Plus standards, introduced in 2018, mandate that new combi boilers achieve at least 92% efficiency to enhance energy usage and reduce carbon emissions.

These regulations include requirements for advanced heating controls like smart thermostats, which optimise heating through automation and environmental data. Future provisions will encourage the integration of hybrid heat pumps and potentially hydrogen-ready boilers.

These efforts are aimed at increasing combi boiler energy efficiency and aligning with the UK’s decarbonisation goals.

Comparing Boiler Prices and Warranties

While price is an unavoidable factor, it should be weighed against long-term benefits. Warranties, for instance, offer coverage for parts and repairs, mitigating potential future costs.

Brands like Worcester Bosch and Viessmann offer warranties that can be extended for added peace of mind. We also have a range of combi boilers under £1,000 (not including installation costs) too which are for people on a budget.

The initial cost for a new boiler installation can fluctuate greatly, so it’s vital to weigh both the immediate expenses and the potential savings from efficiency over time.

Combi Boiler Finance Options

Spreading the cost with our combi boilers on finance options is another way to be able to afford the best without any upfront payment.

Every single boiler in this review is available on a pay monthly plan with Boiler Central.

Government Grants

If you are looking to replace your combi boiler with a greener alternative, the only way you can get a grant is by looking at alternatives such as heat pumps.

In the UK, financial incentives such as the Boiler Upgrade Scheme and ECO4 are designed to promote the use of energy-efficient heating.

The Boiler Upgrade Scheme offers grants to offset the costs of replacing old combi boiler systems with greener alternatives, available to homeowners in England and Wales. The Renewable Heat Incentive, although closed to new applicants, continues supporting existing installations.

Additionally, the ECO4 scheme aims to improve home energy efficiency for low-income households by requiring energy suppliers to assist in upgrading combi boilers and central heating systems.

These programs help make energy-efficient boilers more affordable and encourage long-term energy savings.

Key Features to Look for in a Top Combi Boiler

The heart of your home deserves the best, and when it comes to combi boilers, certain features can make all the difference.

As the name suggests, a combi boiler works by combining heating and hot water in one single unit.

Therefore, whether you live in a compact city apartment or a sprawling suburban home, these key features will ensure your boiler is not just a functional appliance but a smart, efficient, and environmentally friendly addition to your household.

Compact Design and Easy Installation

Space is a luxury, and an efficient combi boiler is a perfect fit for homes where it’s at a premium.

Models like the Viessmann Vitodens 050 and those from the Ideal Logic range are designed to fit snugly into a kitchen cupboard or similar space.

These best gas combi boilers don’t skimp on efficiency either, with some models boasting high energy efficiency ratings of 90% and above and A-rated ErP labels.

In fact, a gas combi boiler can be an ideal choice for homeowners looking to save space and energy.

Features like smart home system compatibility and adaptability to hydrogen blends further enhance their appeal.

Smart Controls and Connectivity

In an age where convenience is king, smart controls in combi boilers allow you to manage your home’s central heating with the touch of a button, wherever you are.

The Greenstar 4000 and Alpha E-TEC Plus, for example, can be paired with smart home devices for remote temperature control and energy usage tracking.

Viessmann’s Vitodens 100-W even offers advanced connectivity, enabling remote access and performance monitoring.

Remote monitoring, assistance & diagnostics

Modern combi boilers are increasingly adopting the Internet of Things (IoT) and AI technologies to enhance efficiency and functionality.

IoT in the way of combi boilers with built-in Wifi such as in the Vitodens 050, enables remote monitoring by manufacturers and control via smartphones, allowing for real-time diagnostics, adjustments and notifications.

AI can contribute through predictive maintenance, using data to foresee and address potential issues before they lead to breakdowns.

Together, these technologies used by Viessmann and other brands not only improve boiler longevity and efficiency but also support energy-saving and reduce carbon footprints.

Buyers looking for the best boilers should consider these smart features to optimise home heating and contribute to environmental sustainability.

Energy Efficiency and Environmental Impact

Energy efficiency is the cornerstone of energy efficient combi boilers. Not only does it affect your energy bills, but it also impacts the boiler’s lifespan.

Regular servicing keeps your combi boiler humming at peak efficiency, while models like the Vaillant EcoTec Pro have an ‘A’ grade rating, reducing both energy costs and carbon footprint.

Moreover, brands like Viessmann and Worcester Bosch are pushing the envelope on environmental sustainability with recyclable packaging for the Greenstar 4000.

Combi Boiler Maintenance and Lifespan

A well-maintained combi boiler is like a well-oiled machine, providing consistent warmth and hot water with minimal fuss. Regular servicing not only keeps your boiler in tip-top condition but also ensures that warranties remain valid.

We will examine the critical aspects of combi boiler maintenance and how to prolong their lifespan.

Regular Servicing

Annual servicing by a certified engineer is not merely a suggestion; it’s critical for maintaining your boiler’s health and efficiency. This regular check-up can nip potential issues in the bud and keep your boiler running smoothly for years.

Furthermore, manufacturers such as Vaillant necessitate annual combi boiler servicing to uphold their warranties, underlining the significance of routine maintenance.

See how much a combi boiler service costs here

Troubleshooting Common Issues

When your boiler hits a snag, a bit of troubleshooting can go a long way. Common issues such as a frozen condensate pipe or low boiler pressure can often be resolved with some basic DIY fixes.

However, for more complex problems, it’s always best to call in the experts to ensure your boiler gets back to working order without risking further damage.

When to Replace Your Combi Boiler

A combi boiler typically lasts between 10 to 15 years. However, signs like frequent breakdowns, obsolete parts, or an uptick in energy bills should set off alarms that it might be time for a replacement.

If you’ve done all the troubleshooting and consulted with an engineer but the issues persist, then investing in a new boiler may be the wisest and most cost-effective solution, especially when considering combi boilers cost.

Hydrogen ready combi boilers

Disclaimer: Hydrogen-ready combi boilers are not available, and boilers running on hydrogen are not new technology; they have been able to do that anyway since 1993.

You may have heard plenty about hydrogen in the news, and currently, everything is up in the air regarding a will they/ won’t they introduce hydrogen-ready boilers. However there is still good reason to cover this subject.

All about hydrogen ready combi boilers in the UK

Here are the main points condensed from the detailed discussion about hydrogen-ready boilers:

• Hydrogen-Ready Boilers: Designed to operate on natural gas and can be converted to use hydrogen, supporting the UK’s shift towards a hydrogen economy.
• Transition Plans: Initial plans were to introduce a 20% hydrogen blend with natural gas by the late 2020s and transition to 100% hydrogen by the mid-2040s. However while there is still huge investment, this is currently obscure.
• Current Capability: Normal gas boilers can currently handle up to 20% hydrogen mixed with natural gas without significant modifications. If ever available, hydrogen ready boilers will be able to run on up to 100%
• Manufacturer Involvement: Companies like Worcester Bosch, Viessmann, and Baxi are developing prototypes and supporting the transition with advanced boiler technologies.

These points encapsulate the strategic importance and developmental status of hydrogen-ready boilers in the UK’s energy landscape, but they look like they will be delayed considerably, if ever.

Summary

As we come to the close of this comprehensive guide, one thing is clear: the combi boiler market in 2024 is rich with options that cater to different needs and preferences.

Whether you prioritise efficiency, smart technology, compact design, or long-term warranties, there’s a combi boiler out there that’s perfect for your home.

The brands and models we’ve explored showcase the best in the industry, each with its unique selling points that set them apart in the crowded market.

Remember, the right combi boiler is not just an appliance; it’s a long-term investment in the comfort and efficiency of your home.

By keeping in mind your specific heating needs, the boiler’s efficiency, and the features that matter most to you, you can make an informed decision that balances initial costs against future savings.

With regular maintenance and a keen eye on performance, your chosen combi boiler will serve you faithfully, keeping your home warm and your hot water flowing for years to come.

Frequently Asked Questions

Which is the most efficient combi boiler?

The most energy efficient combi boilers currently are the Viessmann Vitodens 200-w, Viessmann Vtiodens 100-w and Worcester Bosch Greenstar 8000 combi boilers.

which is the most reliable combi boiler?

The most reliable combi boiler is the Viessmann Vitodens 100-w which has a reliability rating of over 98%. This is due to the stainless steel heat exchanger and premium parts used in these German boilers

Which is the most powerful combi boiler?

The most powerful combi boiler is the Worcester Bosch Greenstar 8000 50kw combi boiler. Read our best 40kw combi boiler guide to see more alternatives for larger homes.

Which is the worst combi boiler?

If you want to know what the worst combi boilers are to avoid at all costs, then stay away from the Baxi 200 and Vokera EasiHeat.

Which is the best 30kw combi boiler?

The best 30kw combi boilers are the Vitodens 050-w 30kw and Worcester Bosch 4000 30kw. Read our guide on the best 30kw boilers here for more information.

How many radiators can a 30kW boiler run?

A 30kW boiler can run 15 to 20 radiators, making it suitable for larger properties.

How do I choose the best gas combi boiler?

When choosing a new combi boiler, consider factors such as hot water usage, property size, available fuel, existing system, boiler types, energy efficiency, and renewable energy options. These considerations will help you make an informed decision.

What is the number 1 boiler in the UK?

The most reliable boiler in the UK is the Viessmann Vitodens 100-W, according to a range of sources. These boilers have been consistently rated highly for performance and reliability.

What is the typical lifespan of a combi boiler?

Combi boilers typically have an average lifespan of 10 to 15 years, but regular servicing and maintenance can help maximise their longevity.