We’re about to tell you what the best combi boiler is, with a side order of what to avoid.
For good measure, we’ll also explain why you might not need the best combi boiler in the UK.
Just like snails at a restaurant, some boilers may surprise you when given the right treatment—in this case, quality installation and maintenance.
Key points:
Worcester Bosch, Viessmann, Ideal, and Vaillant are highlighted as the leading combi boiler brands, known for their reliability, efficiency and aftercare.
Choosing a boiler with high efficiency saves on energy costs and ensures reliable hot water flow, especially for larger households.
Boilers with longer warranties and strong customer support are recommended for added peace of mind.
While premium boilers may have a higher upfront cost, they often provide better long-term value due to their durability & award-winning aftercare & support.
Consider both customer reviews and professional recommendations to make an informed decision.
What Makes a New Boiler the Best?
Is it the brand name, the boiler size, the warranty period, or the efficiency rating? As home energy and gas prices soar, we can make a strong case for the latter. But who is this “Latter,” and why are we protecting them in a strong case?
If you’re in the market for a new combi boiler, you might be wondering how to choose the best model for your needs. In this guide, our team of Which?-approved gas engineers and industry experts have thoroughly compared and analysed some of the top models of 2024, focusing on key performance factors.
Drawing on our extensive experience from installing and repairing over 10,000 boilers across the UK, we rank the best combi boilers as well as the best value options to help you make an informed decision.
What is a Combi Boiler?
Combi boilers are the most popular type of boiler in the UK, primarily because they provide both heating and hot water from a single, compact unit. Ideal for most homes, combi boilers are efficient and space-saving solutions.
What Is The Best Combi Boiler in 2024?
Here’s a summary of the boilers we've reviewed, highlighting those that excel in key areas, which are discussed in detail further below:
Best all-around combi boiler: Worcester Bosch Greenstar 4000 - award-winning, superb warranty & reputation
Most affordable: Alpha NX Combi Boiler - high-quality boiler at a more affordable price point
Most efficient: Viessmann Vitodens 100-W - able to achieve up to 98% efficiency
Best value for small homes: Worcester Bosch Greenstar 2000
Best value for large homes: Vaillant EcoTec Plus
How Did We Choose the Best Combi Boilers?
Our rigorous selection process for the top combi boilers of 2024 was based on a thorough evaluation by our expert team of gas engineers.
We focused on the following critical factors to ensure a comprehensive and unbiased review:
Warranty Period: Extended warranties indicate a boiler’s durability and manufacturer confidence.
Brand Reputation: We assessed reliability through customer reviews and expert insights, including insights from our team, to gauge the reliability and trustworthiness of each brand.
Market Presence: Popularity, as shown by UK sales, reflects performance and customer satisfaction.
Awards and Recognition: Industry accolades, like the Which? Best Buy Award, signal peer and consumer approval.
Which? Survey Results: We used data from an annual survey of 10,000 homeowners and 200 expert engineers.
Aftercare Services: Quality aftercare is crucial for long-term maintenance and customer satisfaction.
Price Range: We evaluated cost-effectiveness across premium and budget models.
Efficiency Ratings: Higher efficiency ratings translate to long-term energy savings.
Technological Features: We assessed innovations like smart home compatibility and usability enhancements.
Availability and Cost of Spare Parts: We considered the ease and affordability of obtaining spare parts for long-term maintenance.
By applying these criteria, we were able to provide a well-rounded assessment of each combi boiler’s performance, value, and suitability for different household needs.
Best Combi Boilers (By Model)
Below is our carefully curated selection of the best combi boilers from top UK manufacturers.
These models stand out for their exceptional customer reviews, long warranties, technical superiority, energy efficiency, robust heating capabilities, and award-winning aftercare support.
We prioritised brands with industry-leading support, as reliable aftercare is crucial when issues arise.
#1 Worcester Bosch 4000 Combi Boiler
Our verdict: The best all-around combi boiler
Specifications:
Warranty: Up to 10 years | Energy Efficiency Rating: A | Output Rating (kW): Available in 25 and 30 kW options | Water Flow Rate (litres/minute): 10.5 or 12.3 depending on the model | Size (mm): 724 × 400 × 310 | Price: Starts from approximately £1,152.99
Pros:
Quieter than many competitors, ideal for noise-sensitive environments.
Works with popular smart home systems like Hive, Nest, and tado°.
10-year parts and labour guarantee through Heatable.
Excellent customer support and aftercare services.
Small footprint, fits easily in tight spaces.
Cons:
It is more expensive upfront compared to budget models like Alpha or Ideal.
Best suited for small to medium-sized homes, not ideal for large homes.
Lacks some of the advanced diagnostics features found in Viessmann models.
In our detailed analysis of available combi boilers, the Worcester Bosch Greenstar 4000 emerged as the best all-around model for 2024. This decision was based on several key factors:
Worcester Bosch has long been a top-tier brand in the UK, consistently earning trust among both installers and homeowners.
The company’s reputation is reinforced by its 14 consecutive Which? Best Buy Awards, a feat unmatched by any other boiler manufacturer.
Additionally, customer feedback is overwhelmingly positive, with a Trustpilot rating of 4.7 out of 5 based on over 17,000 reviews as of May 2024.
The Worcester Bosch Greenstar 4000 series marks a significant advancement in the brand’s innovation, building on the success of the Greenstar I, their best-selling boiler, which it has now replaced. During internal evaluations at Heatable headquarters, several key improvements were identified.
The image above shows the Greenstar 4000 (left) and Greenstar I (right).
Notably, the Greenstar 4000 features a modern digital interface that integrates the control panel and pressure gauge. This new digital pressure gauge is particularly convenient, as it alerts users to pressure changes and signals when a refill is needed, enhancing both usability and maintenance (as shown in the image below).
Ben Price/Heatable
Other notable Greenstar 4000 innovations we think are worth highlighting, include the following:
Quieter Operation: Engineered to operate more quietly than its predecessor, the Greenstar 4000 ensures a less intrusive presence in your home.
Compatibility with Smart Controls: This boiler is compatible with all Worcester Bosch controls and popular third-party controllers like Hive, Nest, and tado°, allowing for seamless integration into smart home systems.
Optimal for Small to Medium-Sized Homes: Its design and capabilities make it ideal for smaller and medium-sized homes, offering efficient heating without the bulk.
Ease of Maintenance: With removable side panels, the Greenstar 4000 is designed for easy access, simplifying maintenance and service tasks.
Extended Warranty: It comes with a 10-year guarantee on parts and labour when purchased through Heatable, providing long-term peace of mind.
High Energy Efficiency: With an ErP rating of 94%, it holds an A rating for energy efficiency, ensuring lower energy bills and reduced environmental impact.
Compact Dimensions: Measuring 710 x 400 x 310 mm, it is compact enough to fit discretely within your home.
Why Choose the Worcester Bosch Greenstar 4000?
Choosing this combi boiler means investing in a product that combines Worcester Bosch's legacy of quality with the latest advancements in heating technology.
Consumers benefit from a system that not only meets but anticipates their heating needs, ensuring reliability, energy savings, and compatibility with the evolving landscape of smart home technology.
The image above shows a Worcester Bosch 4000 installed by the Gas Safe engineers here at Heatable. Get your free quote from us here.
For homeowners looking for a durable, efficient, and user-friendly heating solution, the Worcester Bosch Greenstar 4000 presents an excellent choice that brings together the best of tradition and innovation in boiler technology.
Worcester Bosch is renowned for offering superb customer support and aftercare, which is another crucial reason why we placed this boiler model in the number one spot.
As part of our analysis, when speaking with Allen Hart, a YouTube Gas Engineer with over 30 years of boiler experience, he emphasised the importance of aftercare service:
"The aftercare service offered by the manufacturer is a key factor in choosing a new boiler as you want to know they will be fixed promptly without any issues". - Allen Hart.
Who is the Worcester Bosch 4000 not suitable for?
The Worcester Bosch Greenstar 4000 is an excellent boiler for small to medium-sized homes, offering high efficiency, smart compatibility, and strong aftercare support.
However, it may not be the best choice for larger homes, where the Vaillant EcoTec Pro might be more suitable.
Additionally, those looking for advanced diagnostic features might prefer the Viessmann Vitodens series. The Greenstar 4000’s higher upfront cost could also be a drawback for budget-conscious buyers, who might find better value in models like the Alpha E Tec NX or Ideal Logic+.
Prefer video? Watch our comprehensive breakdown of the Worcester Bosch 4000 in our YouTube video with Gas Engineer Allen Hart below:
#2 Vaillant EcoTec Plus Combi Boiler
Our verdict: The best value combi boiler for larger homes
Specifications:
Warranty: Up to 10 years | Energy Efficiency Rating: A | Output Rating (kW): Available in 25, 32, 35, and 38 kW options | Water Flow Rate (litres/minute): Up to 15.9 depending on the model | Size (mm): Approximately 720 × 440 × 338 | Price: Starts from around £1,100 (may vary based on output and supplier).
Pros:
Ideal for larger homes, offering powerful heating and hot water output.
ErP A-rated for both heating and hot water efficiency.
Quiet Mark certified, ensuring low noise levels.
Compatible with vSMART technology for remote control.
Cons:
More expensive than budget models like Alpha E Tec NX or Ideal Logic+.
Lacks the advanced diagnostic features found in Viessmann Vitodens models.
May be more powerful than needed for smaller properties, leading to inefficiency.
Larger in size compared to Worcester Bosch Greenstar 4000, making it harder to fit in tight spaces.
Vaillant is a prestigious German boiler brand that is renowned for its reliability and high-quality engineering.
According to the Which? annual boiler survey and our internal team of gas engineers, they are credited with being one of the "easiest boilers to repair".
Due to its superb reputation, Vaillant is the second-largest manufacturer of boilers in Europe today.
Notably, in a distinct category of the annual boiler survey by Which? Vaillant emerged as the front-runner, earning a commendable 81% approval rating from 200 independent heating engineers for their gas boilers.
The brand's most popular range of combi boilers - the EcoTec Plus is offered in a variety of sizes including 24kW, 28kW and 30kW along with a 10-year warranty (when purchased via Heatable).
The EctoTec Plus is Vaillant’s premium offering and so unlike their entry-level pure model, it features a more durable stainless steel heat exchanger (shown in the image below).
Ben Price/Heatable
Similar to Viessmann’s Lamda Pro, Vaillant now features IoniDetect - this is a brand-new feature in all of the latest EcoTec models and it essentially operates to ensure that the boiler is combusting gas as efficiently as possible.
It achieves this by constantly monitoring the flame quality and type of gas being used and adapting the gas mixture when required to achieve the best possible efficiencies.
These new-generation flame optimisers are ideal as they allow the boilers to adjust and increase efficiency based on the type of gas being used at the time e.g. if hydrogen is added to the mix, they can then optimise the burn for the greatest efficiency possible. It will also work and adjust accordingly if you use LPG gas too.
Who is the Vaillant EcoTec Plus not suitable for?
The Vaillant EcoTec Plus combi boiler may not be suitable for those on a tight budget due to its higher upfront cost compared to more economical models like the Alpha E Tec NX or Ideal Logic+.
It might also be overpowered for small homes, where a smaller model could be more efficient and cost-effective.
Additionally, its size may not be ideal for homes with very limited space. Finally, those looking for the absolute latest in smart technology might prefer models with more advanced features, such as the Viessmann Vitodens series.
Join Thousands of Satisfied Customers:
We’re proud to be Which? Trusted Traders with over 10,000 glowing reviews on Trustpilot. Check out our Reviews and Testimonials page and watch Adrian’s video testimonial below to see why so many trust us for their heating needs.
#3 Alpha E Tec NX Combi Boiler
Our verdict: most affordable combi boiler
Specifications:
Warranty: Up to 10 years | Energy Efficiency Rating: A | Output Rating (kW): Available in 26 and 33 kW options | Water Flow Rate (litres/minute): Up to 14.1 depending on the model | Size (mm): Approximately 712 × 440 × 255 | Price: Starts from around £700 (may vary based on output and supplier).
Pros:
Lower upfront cost compared to premium models like Vaillant or Worcester Bosch.
Slim design, making it easy to fit in small spaces like kitchen cupboards.
Stainless steel heat exchanger enhances durability compared to aluminium.
Up to 10 years, offering good coverage for peace of mind.
Cons:
Less established than top-tier brands like Worcester Bosch or Vaillant.
Fewer output options (26 and 33 kW) compared to other brands.
Lower flow rate compared to more powerful models like the Vaillant EcoTec Plus.
Lacks some of the advanced technology found in higher-end models.
A relatively new brand in the UK boiler market, in recent years Alpha has built a reputation for offering affordable boilers that don’t cut corners when it comes to reliability or quality and they are now an award winner, being recently crowned as Good Homes-approved.
The Alpha E-Tec NX is the brand’s best-selling combi boiler, offering a level of quality to rival premium brands but at an extremely reasonable price point.
For example, instead of using an inferior aluminium heat exchanger typically seen in rival brands at this price point, Alpha use a stainless steel heat exchanger providing enhanced durability (seen in the image below).
Ben Price/Heatable
Another innovative feature of the NX is that it combines the expansion relief valve and condensate drain.
Why is this good?
It reduces the number of parts, while providing a reliable mechanism for the drainage of excess water and condensate while providing a safety mechanism for modulating system pressure.
These innovative features help to reduce installation time and maintenance.
Who is the Alpha E-Tec NX combi not suitable for?
The Alpha E Tec NX combi boiler may not be suitable for those who prioritise advanced technology and brand reputation, as it lacks some of the cutting-edge features and recognition associated with premium brands like Worcester Bosch or Vaillant.
It may also be less ideal for larger homes with higher hot water demands, as its water flow rate is lower compared to more powerful models.
Additionally, those seeking a wide range of output options might find the limited 26 and 33-kW choices restrictive.
#4 Viessmann Vitodens 100-W Combi Boiler
Our verdict: the most efficient combi boiler
Specifications:
Warranty: Up to 12 years | Energy Efficiency Rating: A | Output Rating (kW): Available in 26, 30, and 35 kW options | Water Flow Rate (litres/minute): Up to 14.1 depending on the model | Size (mm): Approximately 700 × 400 × 350 | Price: Starts from around £900 (may vary based on output and supplier).
Pros:
Includes features like Wi-Fi connectivity and smart home compatibility.
Stainless steel heat exchanger enhances longevity and reliability.
Offers up to 12 years of warranty when installed by a Viessmann-trained engineer.
A-rated for energy efficiency, capable of up to 98% efficiency.
Cons:
More expensive upfront compared to budget models like Alpha or Ideal.
While compact, it may still be slightly larger than some other models, limiting placement options.
Fewer output ratings compared to some other models.
Advanced features may require a more knowledgeable user or professional setup.
The Viessmann Vitodens 100-W is the best-selling combi boiler from the award-winning brand and has an impeccable reputation.
Viessmann was previously awarded the Which? Best Buy Award from 2017 to 2020 and since their introduction to the UK market has made continued efforts to improve the availability of spare parts.
The Viessmann Vitodens 100-W comes in a pretty compact size for a wall-mounted combi boiler.
Our Head of Sales, Phil Cox, has a special preference for this combi boiler, leveraging his extensive experience as the former Director of Sales at British Gas.
"With over 30 years in the boiler industry, my recommendations are based on three key factors: reliability, efficiency, and ease of installation. While all options have their merits, my preference leans towards the lesser-known Viessmann."
The image above shows a Viessmann Vitodens 100-W installed by the team here at Heatable. Get a free quote from us here.
Its compact size allows it to fit in most standard kitchen cupboards and ensures it isn’t an eyesore when installed in a living space.
"What sets it apart is its impressive connectivity, allowing for remote access to the boiler, performance monitoring, and the ability to diagnose potential faults. This feature is a significant advantage not only for businesses but, more importantly, for our valued customers.” - Phil Cox, former Director of Sales, British Gas.
Who may the Viessmann 100 may not be suitable for?
The Viessmann Vitodens 100-W may not be suitable for those on a tighter budget, as its premium price surpasses more economical options like the Alpha E Tec NX or Ideal Logic+.
While it offers advanced technology and high efficiency, these features might be more than necessary for smaller homes or those with simpler heating needs.
For those who require greater power or additional output options, alternatives like the Vaillant EcoTec Plus or Worcester Bosch Greenstar 4000 might be more appropriate, offering similar reliability at potentially lower prices or with more tailored output options.
Additionally, the complexity of Viessmann’s advanced features might be overwhelming for users seeking a more straightforward system.
#5 Worcester Bosch Greenstar 2000 Combi Boiler
Our verdict: best value for small homes
Specifications:
Warranty: Up to 6 years (with extended options available) | Energy Efficiency Rating: A | Output Rating (kW): Available in 25 and 30 kW options | Water Flow Rate (litres/minute): Up to 12 depending on the model | Size (mm): Approximately 724 × 400 × 300 | Price: Starts from around £750 (may vary based on output and supplier).
Pros:
Lower upfront cost compared to other Worcester Bosch models like the 4000.
Slim and compact, making it suitable for small spaces like kitchen cupboards.
Operates quietly, making it ideal for smaller homes or flats.
Backed by Worcester Bosch’s strong reputation for reliability.
Cons:
Standard 5-6 year warranty, which is shorter than the 10-year warranty offered by higher-end models.
Lacks some of the advanced features and smart technology compatibility found in more expensive models.
Lower water flow rate compared to more powerful models like the Worcester Bosch 4000.
Less comprehensive aftercare options compared to premium models.
The Worcester Bosch 2000 is the brand's new, entry-level (budget) boiler, ideal for those looking for an industry-leading boiler at a competitive price.
It’s both compact and officially recognised as the brand's quietest boiler, hence why it’s perfect for small homes with one bathroom, exactly what it was designed for.
A common concern in small properties is noise, so it’s reassuring to know that this boiler will operate without causing a scene.
Its compact dimensions also mean it can be installed in small spaces, ideal for properties with limited space.
For example, it can be installed between kitchen cupboards and won’t typically stick out.
The 2000 offers the same contemporary design and feel as its more expensive big brother, the 8000, so if you want a boiler with a more refined aesthetic, the 2000 is a good option.
Ben Price/Heatable
A distinctive feature of the Greenstar 2000 is its removable side panels (image below), which make servicing and repairs more efficient. This design allows for easier access to internal components, potentially reducing labour time and installation costs compared to boilers with a typical front-only access design.
Ben Price/Heatable
Who may the Worcester Bosch 2000 not be suitable for?
The Worcester Bosch 2000 may not be suitable for larger homes due to its limited output options (25 and 30 kW), which may not provide enough power for higher heating and hot water demands.
It also offers a shorter warranty (up to 6 years) compared to other models, which might not be ideal for those seeking longer warranty protection.
Additionally, it lacks some advanced features and higher water flow rates found in more premium models, making it less suitable for those requiring more robust performance or advanced technology.
Have issues with your combi boiler? Read our boiler problems and solutions for quick troubleshooting guidance.
Best Combi Boilers UK Comparison Table:
In the table below you can compare the key metrics between some of the best combi boilers currently available in the UK:
Boiler Model: | Vaillant ecoTec Plus (36 kW) | Alpha E-Tec NX (33 kW) | Vitodens 100-W (35 kW) | Viessmann Vitodens 111 (32 kW) | Viessmann Vitodens 050-W (35 kW) | Worcester Bosch Greenstar CDi Compact (36 kW) | Vaillant ecoFit Pure (35 kW) | ||
Best Boiler For: | All-round combi boiler | Larger homes | Budget-friendly | Powerful boiler | Larger homes | Award-winning, premium model | Mid-range boiler | Small spaces | Compact design |
Efficiency | 92% | 94% | 93% | 92% | 93% | 94% | 92% | 91% | 94% |
Power Output (kW) | 30 | 36 | 33 | 35 | 32 | 35 | 35 | 36 | 35 |
Product Warranty | 10 years | 10 years | 10 years | 12 years | 10 years | 10 years | 10 years | 10 years | 10 years |
Water Flow Rate (Litres/Min) | 12.3L flow rate
| 17.0L flow rate
| 14.1L flow rate | 14.3L flow rate
| 18L flow rate | 14.3L flow rate
| 12.2L flow rate | 14.7L flow rate
| 14.1L flow rate
|
Size (Dimensions) | 724 (h) x 400 (d) x 310 (w)
| 720 (h) x 352 (d) x 440 (w) | 712 (h) x 440 (d) x 225 (w) | 700mm (h) x 360mm (d) x 400mm (w) | 950mm (h) x 600 mm (d) x 500mm (w)
| 780mm (h) x 365mm (d) x 440mm (w) | 700 (h) x 300 (d) x 400 (w) | 690mm (h) x 280mm (d) x 390mm (w) | 700 (h) x 390 (d) x 295 (w) |
Weight | 34.9kg | 37kg | 33.3kg | 35kg | 68kg | 37kg | 37kg | 43kg | 33kg |
Which? Award Winner? | Yes | No | No | Yes | No | Yes | Yes | Yes | No |
Table data: last updated July 2024.
Best Combi Boiler Manufacturers
Here are our top 6 best combi boiler brands in the UK right now, in 2024:
#1 Worcester Bosch Combi Boilers
#2 Vaillant Combi Boilers
#3 Alpha Combi Boilers
#4 Viessmann Combi Boilers
#5 Ideal Combi Boilers
#6 BAXI Combi Boilers
#1 Worcester Bosch Combi Boilers (Best boilers)
A prestigious name within the heating industry and probably the UK’s best, most sought-after combi boiler, historically. One of three combi boilers with the Which? Best Buy award and you can’t go far wrong with a Worcester.
Why do we think Worcester offers the best combi boilers?
Which? Best Buy Award for 14 years
10-year guarantee (when purchased via Heatable)
Availability of parts is second to none
Excellent customer reviews and aftercare
Want a new Which? Best Buy boiler with professional installation?
You can see the latest price on Worcester Bosch boilers here.
Worcester 2024 combi boiler range & overviews:
Worcester Bosch Model | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs |
Worcester Bosch Greenstar i (discontinued) | - | - | 25kW | 30kW |
- | - | 25kW | 30kW | |
Worcester Bosch Greenstar Si Compact | - | - | 25kW | 30kW |
Worcester Bosch CDi Classic (discontinued) | 29kW | 34kW | 38kW | 42kW |
- | 28kW | 32kW | 36kW | |
Worcester Bosch CDi Highflow | - | - | 29kW | 30kW |
24kW | - | - | 30kW | |
30kW | 35kW | 45kW | 50kW |
Greenstar 2000 Combi Boiler
The brand's entry-level offering.
The Worcester Bosch 2000 is the brand's entry-level combi boiler and is officially their quietest model to date.
It is designed to fit into small spaces e.g. kitchen cupboards and features easy-to-remove side panels for convenient servicing and maintenance.
Like all of the latest boilers from the brand's updated Greenstar range, the 2000 also benefits from the super sleek, contemporary design and digital interface.
Ideal for: Those looking for an entry-level, super-quiet boiler from an award-winning brand.
Boiler specifications:
Warranty: 5 years standard or up to 10 years when installed by Heatable
Energy efficiency rating: A
Output rating (kW): 25, 30
Water flow (litres/min): 16.4
Size (mm): 700 x 300 x 400
Greenstar 4000 Combi Boiler (Best all-around combi boiler)
The brand's mid-range combi boiler.
The Greenstar 4000 is a brand new arrival to the Worcester Bosch range of combi boilers, designed to replace the best-selling Greenstar i range.
The Worcester Bosch 4000 offers everything the i range did but with some major improvements, including a quieter operation and a higher hot water output.
The 4000 benefits from a new, sleek curved edge case, user-friendly digital display and easy-to-use push control buttons, a major improvement on the boring square boxes of old.
Read our complete, in-depth review of the Worcester Bosch 4000 here.
Ideal for: Those looking for a mid-range boiler from an award-winning brand.
Boiler specifications:
Warranty: 5 years standard or up to 10 years when installed by Heatable
Energy efficiency rating: A
Output rating (kW): 25, 30
Water flow (litres/min): 16.4
Size (mm): 710 x 310 x 400
Greenstar i Combi Boiler (Most popular in terms of sales)
The Greenstar 30i is Worcester’s best seller and over a million of them are in homes throughout the UK. If choosing between the two, then do consider opting for the Greenstar 30i over the Greenstar 25i as they are known to be much more reliable and often don't have too much disparity in price.
If you do have a super small property though, then the 25i will be more than adequate and could secure you a hell of a Worcester bargain.
Note: This boiler has now been replaced by the new and improved Greenstar 4000 (listed above).
CDi Compact Combi Boiler
A combi boiler designed for small spaces.
Another range-topper from Worcester Bosch boilers with more compact dimensions for homes short on space. The CDi compact is still complete with outstanding efficiency levels, a Which? Best Buy award and can still pack a punch for its size – comfortably powering homes with two bathrooms.
Ideal for: Ideal for: Those looking for a powerful and compact boiler that can squeeze into a tight spot e.g. kitchen cupboards.
Read our in-depth Worcester Bosch Greenstar CDi Compact Review.
Worcester Bosch 8000 Style (Replacing the CDi Classic)
The brand's premium combi boiler model.
Worcester's most powerful and connected wall-hung boiler to date, capable of delivering up to 50kW's, and with optional smart technology that will top up the boiler for you when low pressure is detected.
As its name suggests, it is also arguably the best-looking boiler on the market and readily available in black - a boiler industry innovation on par with the introduction of the iPod.
Ideal for: Ideal for: Those looking for a top-of-the-range boiler, with all of the latest and greatest features.
Read our in-depth reviews of some of the most popular models from the brand:
Learn all about combi boilers in our what is a combi boiler guide and see how the brand fared against Baxi in our Worcester Bosch vs Baxi comparison.
Greenstar Si Compact Combi Boiler
Very similar to its namesake, the Greenstar Si boasts almost identical statistics and features and again is suitable for small to medium homes with one bathroom but a smaller frame allows this model to nestle into a kitchen cupboard – it's probably the best option if you require your combi boiler to be out of sight.
Ideal for: Those looking for a powerful boiler that can fit into small spaces.
Check the latest deals on Worcester Bosch boilers here.
CDi Classic Combi Boiler (Discontinued)
A truly premium boiler from Worcester and their top-of-the-line offering, in their opinion, it's probably the best combi boiler in their range.
If you have your heart set on a Worcester then this is certainly one model to consider, although it may come with a more premium price tag.
Note: The CDi Classic has been replaced by the Greenstar 8000 (listed above).
Have you had a boiler quote yet? Use our calculator to get an instant new boiler quote.
CDi Highflow Combi Boiler
A monstrous floor-standing combi boiler with industry-leading hot water flow rates. Perfect for large homes with multiple bathrooms that don’t want to make way for an additional water tank. It's the best combi boiler for massive homes, not many can match its credentials.
Ideal for: Those looking for a combi that can handle super high hot water demands.
Do you have a large home? You may be interested in reading our guide on the best 40kW combi boilers
Worcester the way? We think so.
Worcester Bosch boilers are without a doubt one of the best boiler brands in terms of reliability and you can bag yourself a 10-year warranty (assuming you buy from a Worcester Approved Installer and not a rogue in an unmarked white van) giving you peace of mind no matter what.
Check the latest price on a Worcester boiler here.
If you purchase a new Worcester Bosch boiler via Heatable, you will indeed secure yourself a lengthy 10-year guarantee.
If you’re hellbent on getting a Worcester and quality is your top priority, you may want to consider exploration beyond the Greenstar i range - where Worcester's real quality lies - the 8000 Style is a great place to start.
However, unlike other manufacturers, irrespective of your chosen Worcester Bosch model - you can always bank on Worcester's outstanding aftercare which is without a doubt, industry-leading.
You can check the latest deals on Worcester Bosch boilers here, and see how the brand compared to another market leader in our Worcester Bosch vs Vaillant Boilers post.
They're award-winning boilers: Voted Which? Best Buy for 10 consecutive years
As one of the most credible and respected consumer awards - it's an award, unlike others, that you simply can't buy.
The brand won the “Best Buy” award based on feedback from actual real humans (not pretend ones). They also gathered feedback from over 100 installers.
Moreover, the brand's boilers received several high 5-star ratings the consumer choice organisation considers most important to consumers, including full marks for their build quality and availability of parts and spares.
If your Worcester Bosch boiler's losing pressure, get a fixed price replacement, online.
How much will the installation of a new combi boiler cost? Check out our new boiler costs guide for the full rundown.
What factors do you need to consider when having a new combi fitted? Find out in our combi boiler installation guide.
#2 Vaillant Combi Boilers (2nd Best Boilers)
Another proud owner of a Which? Best Buy award and a huge player in the British boiler market. Vaillant is a time-served and well-respected boiler manufacturer and is certainly among the premium contenders.
Vaillant combi boilers are made in the UK to impeccably high standards, they’re already in a staggering amount of UK homes, offer excellent warranties, and are loved by boiler installers too.
Did you know that you could pay for your money in monthly instalments using boiler finance options.
Vaillant's 2024 combi boiler range & overviews:
Vaillant Model | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs |
ecoTEC exclusive | - | - | 35kW | |
25kW | 32kW | 35kW | 38kW | |
ecoTEC plus store | - | - | - | 38kW |
24kW | 28kW | 30kW | - | |
ecoFIT pure | - | 25kW | 30kW | 35kW |
Vaillant ecoTEC Pro Combi Boiler
Vaillant's entry-level combi option.
The perfect combi boiler solution for small to medium homes with the kW model’s coming in three different outputs to suit all.
A bright LCD display makes the ecoTEC pro super simple to use and it also comes with a Quiet Mark award so it’s not going to wake you up whilst warming your home in the morning.
Ideal for: Ideal for: Those looking for Vaillant's entry-level combi boiler.
Vaillant ecoTEC plus Combi Boiler
The brand's mid-range combi model.
A broad range of kW outputs starting from 25kW makes Vaillant’s ecoTEC plus the combi allrounder for almost any small to medium home.
Excellent efficiency ratings, premium components and the addition of the Quiet Mark award for quiet operation make this Vaillant’s flagship boiler.
Ideal for: Ideal for: Those looking for Vaillant's entry-level combi boiler.
Ideal for: Anyone looking to secure themselves Vaillaint's mid-range or so-called 'flagship' combi.
Vaillant ecoTEC exclusive Combi Boiler
The brand's premium offering.
Available in outputs at the higher end of the scale -35kW and 43kW, the ecoTEC exclusive is a premium combi boiler for larger homes that boasts an impressive 17 litres of hot water per minute.
Indeed impressive if you like lotsa' hot water.
Ideal for: Those looking for a powerful combi boiler with a durable stainless steel heat exchanger and built-in energy-saving tech.
Vaillant ecoTEC plus store Combi Boiler
A combi with built-in water storage.
It's a beast of a storage combi boiler that’s premium in every manner.
A hot water delivery rate of up to 20 litres per minute that you would struggle to find elsewhere makes this an outstanding choice for larger homes if you don’t want to, or have the room to fit an additional water storage tank.
Ideal for: Those with high hot demands, looking for a combi boiler that can handle it, equivalent to the Viessmann 111.
Curious to know which condensing boiler brand performed worst? Find out in our report on the worst boilers.
Vaillant ecoFIT pure Combi Boiler
The brand's super-compact model.
Another super-efficient combi boiler suitable for almost any sized home with the added bonus of being extra compact, if you’re shy on cupboard space or a boy wizard, lives under your stairs.
It’s clever too – automatically reducing its energy usage to lower your bills.
Ideal for: Those looking for a super-compact combi boiler that can squeeze into cupboards.
Order today & get your Vaillant installed tomorrow:
If you’re considering a new Vaillant boiler, smart choice. Vaillant is a time-tested boiler brand with an impeccable reputation and collection of awards.
Recommended: Check out our top 10 list of the best boiler manufacturers for a complete rundown of the best boilermakers.
If you are interested in the Vaillant ecoTec get a fixed price on a brand new model with gas-safe installation as quickly as tomorrow.
Got an emergency? If your boiler is busted and you have no hot water, you may be interested in our emergency boiler installation guide.
Do you have a Vaillant and are experiencing the F28 code? Read our full guide on the Vaillant F28 error.
#3 Alpha Combi Boilers (3rd Best Boilers)
Alpha Innovation or simply Alpha boilers are a relatively new brand in the UK's domestic boiler market but has quickly made a name for itself, thanks to their reliability and affordability.
Made in the heart of Italy and with a headquarters based in Kent, this manufacturer offers a comprehensive range of boilers that on a technical level rival market leaders.
There's no doubt that Alpha offer the top combi boilers for those on a budget.
Why else do we think Alpha boilers are a great choice?
Good Homes Magazine Approved.
10-year guarantee (when purchased via Heatable).
Superior build at an affordable price point.
Alpha's 2024 combi boiler range & overviews:
Alpha Model | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs |
- | 28kW | 38kW | |
Alpha E-Tec Plus | - | 28kW | 38kW |
Alpha Evoke | - | - | 38kW |
Alpha E-Tec NX | - | 28kW | 33kW |
Alpha NX Combi Boiler
Alpha's most popular combi boiler.
The Alpha NX is the brand's latest combi boiler, replacing their best-selling Alpha E Tec and offers a level of quality to rival premium manufacturers but at a budget-friendly price point.
For example, they utilise a stainless-steel heat exchanger which is usually something you would only expect in a premium brand.
Alpha offers a warranty of 7 years on their Alpha NX, but Heatable offers an exclusive 10-year warranty, which also matches some of the premium brands.
Ideal for: Those looking for high quality and reliable boiler at an affordable price point.
Interested in the Alpha E-Tec NX? Get a fixed price on a brand-new model with gas-safe installation as quick as tomorrow.
#4 Viessmann Combi Boilers (4th Best Boilers)
Viessmann is already an astronomical force in the European boiler market and also leads the way in commercial boiler installations.
Now they’re here to bestow their majestic German engineering upon the UK domestic market providing your home with a new boiler so good, you can forget about it for good this time.
Why do we think Viessmann offers some of the best combi boilers?
Which? Best Buy Award winner - titled as the UK's "most reliable boiler".
10-year warranty (when purchased via Heatable).
State-of-the-art German engineering - no plastic or rubber components (like some competitors).
Patented Inox Radial Stainless Steel Heat exchanger (not aluminium found in inferior brands).
The only boiler with Lamda combustion control - maximising efficiency.
Hydrogen ready - for the next generation of fuel.
The availability of parts is second to none.
Excellent customer reviews and aftercare.
Want a new Which? Best Buy boiler with professional installation?
You can see the latest price on Viessmann boilers here.
Viessmann’s 2024 combi boiler range & overviews:
Viessmann Model | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs |
- | 29kW | 35kW | |
26kW | 30kW | 35kW | |
Vitodens 200-W | - | - | 35kW |
26kW | - | 35kW |
Boiler not working? Fancy a Viessmann? Get your fixed price online. We can install it in as little as 24 hours.
Viessmann Vitodens 050-W Gas Combi Boiler
The brand's entry-level offering.
Available in two kW outputs suitable for any home requiring a new combi boiler, the Viessmann Vitodens 050-W is the trusty workhorse of the Viessmann family.
It has a price to compete with boilers that don’t scratch the surface of its quality whilst maintaining high component standards – most importantly of all, their patented Inox-Radial stainless steel heat exchanger (essentially a part in other boilers that’s likely to break and Superman would struggle to crack this one).
Oh – and it has a Which? Best Buy award, only bestowed on the greatest of boilers and in response to feedback from thousands of real customers and industry experts.
Ideal for: Those looking for an entry-level model from an award-winning brand.
Like the Viessmann Vitodens 050-W? Get a fixed online price, including installation as quick as tomorrow.
Viessmann Vitodens 100-W Combi Gas Boiler
The brand's mid-range combi boiler with a powerful punch.
Everything that makes its little brother Vitodens 050-W the super boiler it is and more. The Viessmann Vitodens 100-W should be any homeowner's go-to combi boiler.
A familiar endorsement from ‘Which?’ for its remarkably high-end internal parts, a class A rating for efficiency, back-lit LCD display, low fan speed for quiet operation and low CO2 emissions to help ease your carbon footprint and conscience. This is Viessmann’s, Lebron James.
Upgrades on the 100-W vs the 050-W include a larger LCD display with additional options, a superior Printed circuit board (essentially the brain of the boiler) and additional power output options.
The 100-W is also manufactured and assembled in the German Viessmann factory, while the 050-W is assembled in Turkey.
Ideal for: Those looking for a powerful, mid-range combi boiler.
Viessmann Vitodens 200-W Combi Boiler
The brand's range-topping boiler model is perfect for larger homes.
Meeting every demand a boiler buyer could possibly have for their combi boiler.
The Vitodens 200-W is perfectly suited for larger detached and semi-detached homes.
It holds every feature and perk of Viessmann boilers before it whilst also boasting a colour touchscreen display, smart thermostat compatibility and up to an incredible 98% efficiency rating.
Ideal for: Those looking for the top-of-the-range combi boiler from the award-winning German brand.
Like the Viessmann Vitodens 200-W? Get a fixed online price.
Check out our full guide on choosing a boiler for a large home.
Viessmann Vitodens 111-W Storage Combi Boiler
A combi with built-in water storage, ideal for homes with high hot water demands.
The only thing Viessmann can be accused of is a lack of imagination when it comes to naming their boilers, but their quality does all of the talking.
The Vitodens 111-W is a monstrous storage combi – essentially rendering it a kind of beautiful Frankenstein boiler – halfway between a combi and a regular boiler delivering a ludicrous 18 litres of hot water per minute.
Lucky enough to have that huge house you always wanted? Get luckier and get yourself the Vitodens 111-W.
The 111 boiler model can fill a bath in just 8 minutes while simultaneously supplying a sink or washbasin.
Ideal for: Those looking for a boiler capable of meeting extremely high hot water demands, without the necessary space for a system boiler and tank.
Like the massive Viessmann Vitodens 111-W Storage Combi hybrid? Get a fixed online price.
Typical Viessmann Combi boiler prices 2024 (ours are the best!):
Viessmann Model | |
Vitodens 050-W 25kW | |
Vitodens 050-W 30kW | |
Vitodens 050-W 35kW | |
Vitodens 100-W 25kW | |
Vitodens 100-W 26kW | |
Vitodens 100-W 30kW | |
Vitodens 100-W 35kW | |
Vitodens 200-W 35kW | |
Vitodens 111-W 26kW | |
Vitodens 111-W 35kW |
Please note: The above prices assume a straightforward swap of a new, replacement combi boiler. To get the best accurate price, click the get quotes button. Or, for a massive, in-depth article on prices, check out our new boiler costs article.
If time eluded you and you didn’t have time to read the life-changing Viessmann overview above, then do read this brief conclusion.
Want to save money and energy on your heating bills? If so, you should consider installing one of the best smart thermostats.
What's more, Viessmann offers some of the best boilers in class when it comes to efficiency too.
The Energy Saving Trust make it clear:
If you replace your old G rated boiler with an A-rated boiler and set of heating controls (you can even operate it remotely via an app on your phone) you could save about £385 and 1,500kg of carbon emissions a year.
If Viessmann's really are the best gas combi boiler, why are they so cheap?
Heatable has a unique business model, allowing us to offer all our Viessmann’s with a 12-year warranty at mind-bogglingly low prices.
But truthfully – Viessmann boiler prices will very shortly be on the rise and such bargains are much harder to come by.
Right now, Viessmann is priced so well to increase their exposure to Britain’s domestic boiler buyers but as their quality becomes more than just rumour – their prices will inevitably rise to reflect just how premium of a product they really are.
The best-rated combi boiler of 2024, may soon become the most expensive.
Viessmann Boilers sponsor Huddersfield Football Club and since this engagement, the Huddersfield players have been so distracted by the beautiful heating machines in their homes, that they’re practically guaranteed relegation from the Premier League this year – all without a care in the world. That’s the power of Viessmann.
*2024 update - Huddersfield were indeed, relegated.
Viessmann boilers' quality comes from within – literally. A boiler is the sum of all its parts and internal components that make or break them.
Viessmann never compromises on the quality of their build - it’s a German thing. They only accept the best. Their boiler range is littered with endorsements from Which? all so readily backing up their already unrivalled features and statistics.
Did you know our boiler installation cost calculator only takes 60 seconds to complete? Using a series of multiple-choice questions, it can provide you with a fixed price on a range of budget-friendly boilers.
Did we mention that Viessmann is the UK’s most reliable boiler? If nothing else swings it for you, that alone, should.
Don't just take our word for it either...
In the Which? Annual Boiler Survey Viessman received an overall review rating of 84% based on reliability, customers' overall scores, and engineer’s opinions.
Convinced that the Viessmann combi range is the best for you? Get a fixed online price today and get your installation as quickly as tomorrow.
Read our Worcester Bosch vs Viessmann Boilers review if you need some help in choosing between these two popular brands.
Do you have limited space in your home? Check out our guide on the best small boilers.
Want the exact price of a new boiler? Use our boiler quote calculator (your fixed price will appear on the screen).
#5 Ideal Combi Boilers (5th Best Boiler Brand)
Joyful wordplay aside, an Ideal combi boiler might just be the ideal boiler for your home.
Ideal boilers have been a mainstay in the British boiler market for what seems like an eternity. Picture a horse that relentlessly finishes in the top 6 at the Grand National but never quite gets its nose in front – no cigar but you know that horse is from a damn good stable.
Ideal is all about inclusivity and range – their combi boilers range from budget to bedazzling and everything in between meaning they cater to the folks funding their boiler replacement with change found down the side of their couches, as well as those looking for the best boiler money can buy (see; Ideal Vogue).
Ideal’s 2024 combi boiler range & overviews:
Ideal Model | Kilowatt (kW) outputs | Kilowatt (kW) outputs | Kilowatt (kW) outputs |
Logic | 24kW | 30kW | 35kW |
Vogue Gen2 | 26kW | 32kW | 40kW |
Vogue Max | 26kW | 32kW | 40kW |
Do you have a back boiler and want it replaced with a modern combi boiler? Ideal looking like an ideal choice? Get a fixed online price
Ideal Logic Combi Boiler
The brand's entry-level combi boiler.
Ideal, Logic, Vogue. Ideal’s marketing team don’t like unnecessary syllables and loves assigning words to their products that already hold positive connotations.
Fortunately, their technical team do tend to back this up.
The Logic combi is without a doubt a logical choice for any grudge purchase boiler installation.
Are the odds of your boiler breakdown being expected and affordable? We’ve checked, and it’s 3%. The Ideal Logic is a no-thrills, solid boiler that’s popular for its price-to-quality ratio. Ideal offers a 2-year standard warranty providing you with the required peace of mind – not bad for a dual award winner.
Ideal Logic combi's best boiler perks:
Made in the UK - so you know it's good
Compact in size (ideal for cupboards)
Roughly as difficult to program as peeling a banana
Won the Queens Award in 2013
Won Good Housekeeping Awards 2013 & 2017
2-year warranty as standard
Want the best price on a new Combi Boiler? Get a fixed online price with installation within 24 hours.
Ideal Vogue Combi Boiler
Their mid-range model.
Weary of churning out their regular award-winning boilers, Ideal set out to make a boiler to break the mould.
The Ideal Vogue Gen2 is Ideal’s best, premium offering, also picking up numerous awards, it has been blessed with internal component upgrades, a backlit LCD colour display, a standard 10-year warranty, built-in frost protection and an endorsement from the Energy Saving Trust for its outstanding efficiency and global warming protest organisational skills.
Ideal Vogue Max Combi Boiler
Ideal's range-topping combi option.
If it isn't broken, don't fix it. Ideal to know that it's just plain logic. So their Vogue Max is just their regular Vogue but with an added Ideal-approved water filter, magically increasing their already whopping 10-year warranty to an unprecedented and industry-leading, 12 years. It's the best boiler in its class in terms of warranty length vs. cost.
Read the Ideal Vogue Max Combi Boiler Review.
A note on the head-turning, heart-breaking, bone-chilling aesthetics of the Ideal Vogue:
This Adonis of a heating machine looks like a groomed wild boar, purring with unshakeable self-certainty but at the same time, exuding the divine grace of a gliding swan. Some of the UK’s oldest ducks cower in shame at the ease of which water rolls off this machines back.
Typical Ideal Combi Boiler prices (we offer the best online prices, period!):
Ideal Model | |
Logic Combi 24kW | |
Logic Combi 35kW | |
Vogue Gen2 26kW | |
Vogue Gen2 32kW | |
Vogue Max 26kW | |
Vogue Max 32kW | |
Vogue Max 40kW |
Please note: The above prices assume a straightforward swap of a new, replacement combi boiler. To get the best accurate price, click the get quotes button.
For the best budget combi boiler, as of 2024, we would recommend the Alpha E Tec, but for those looking for something a little more premium, then the Viessmann or Worsceter range is certainly worth looking into. These are some of the best boiler brands available, and that's why we fit them. You won’t find a better combi boiler in the Alpha boilers range in 2024.
#6 BAXI Combi Boilers (6th Best Boiler)
Nobody has ever been struck with such elation after being offered a BAXI boiler that they’ve moonwalked to work the next day and offered their colleagues a poorly baked lemon drizzle cake – but perhaps they should.
Baxi might not be considered amongst the premium boilers of the market but they certainly have some premium products backed up by award-winning customer service and excellent warranties so if you’re looking for a bargain, you might just find it in a BAXI.
BAXI combi boiler range & overviews:
Baxi Model | |
100 Combi | |
200 Combi | |
400 Combi | |
EcoBlue Advance | |
EcoBlue + | |
Platinum |
We know what you're thinking:
So many Baxi boilers and so little time and why do Baxi avoid prime numbers in the combi models like they know something we don't.
Baxi has more combi boilers than we would care to run through but if you’re looking for top quality and aiming for that reassuring 10-year warranty mark, make sure you aim for the Baxi 600, the Baxi duo-tec, the Baxi EcoBlue range or the Baxi Platinum.
Consider avoiding the Baxi 100, 200 & 400 range if you’re looking for a premium standard and long warranty.
If your radiator is cold at the bottom, it may be a sign of a faulty boiler valve, in which case getting your new boiler replaced may be appropriate, check out the Worcester Bosch Greenstar 30i, which you can purchase through us.
Interested in a Baxi? Read our Baxi Duo Tec 28 Combi boiler review and the Baxi 600 Combi boiler review.
Most reliable combi boiler
Choosing a reliable boiler is often at the top of the list for many, but how do you objectively determine which boiler is the most reliable?
There are three major metrics you can use:
The boiler’s warranty length - a long warranty is a sure sign the manufacturer trusts the long-term reliability of their product
The boiler manufacturers’ customer reviews and average ratings
The boiler’s build e.g. does it use a stainless steel heat exchanger, plastic parts etc
With these in mind, the clear winner is Worcester Bosch, specifically the Worcester Bosch 8000 combi boiler.
This boiler comes with a 10-year guarantee on the parts and labour and the brand has been a Which? Best Buy for 14 years running - an achievement held by no other manufacturer.
On third-party review platform Trustpilot, the brand has amassed over 40,000 reviews with an average rating of 4.6 out of 5 - considered ‘excellent’.
Do you live in a great, big house? Read our guide on the best boilers for large homes.
Read the Vitodens 100-W Combi Boiler Review.
Want to have your combi boiler moved to a different location? Check out "cost of moving boiler" guide.
Most affordable combi boilers
Alpha E-Tec NX Combi Boiler
Alpha's most popular combi boiler.
The Alpha E-Tec NX is the brand's best-selling combi boiler and offers a level of quality to rival premium manufacturers but at a budget-friendly price point.
For example, they are built with a stainless-steel heat exchanger which is usually something you would only expect in a premium brand.
Alpha offers a warranty of 7 years on their Alpha E Tec, but Heatable offers an exclusive 10-year warranty, which also matches some of the premium brands.
Ideal for: Those looking for high quality and reliable boiler at an affordable price point.
Interested in the Alpha E-Tec? Get a fixed price on a brand-new model with gas-safe installation as quickly as tomorrow.
Best energy-efficient combi boilers
All modern combi boilers use condensing technology and are considered A-rated and by law must be at least 92% efficient.
This means they convert 92% of their energy into heating, with only 8% wasted. In financial terms, this means that for every £1 spent on your heating, 8p is wasted.
However, some boiler brands have now exceeded this standard. For example, the Viessmann Vitodens 100-W should be any homeowner's go-to combi boiler boasting an industry-leading efficiency rating of 98%.
According to the Energy Saving Trust by replacing your old G-rated non-condensing boiler with a modern A-rated condensing boiler you could save as much as £380 a year.
You can read our complete review of the most energy-efficient gas boilers here.
Get a Quote for a New Combi Boiler Today
If you’re aiming to get the best deal on a new boiler, consider getting a quote from us, here’s why:
Gas Safe installation within 24 hours.
Thousands of satisfied customers with an average score of 4.9 on Trustpilot, surpassing the market leader.
Which? Trusted Trader: Heatable is proudly recognised as a Which? Trusted Trader.
Price match guarantee: We will match any like-for-like cheaper quote.
Flexible payment options, including interest-free finance.
Up to 12-year guarantee on selected boilers.
Fixed price guarantee: No hidden costs.
Save your quote and decide later.
Get an instant fixed price on a new boiler, here.
To learn more about boilers, visit our advice section, check out our YouTube channel, or read customer testimonials here.
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