Selecting the ideal combi boiler can be difficult. The five top combi boilers for 2022 are the results of our analysis of several different products.
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Our suggested manufacturers and installers of boilers
A combi (or combination) boiler is the most typical source of energy for central heating in a home. When compared to traditional boilers, combi boiler systems are much smaller in size because they don’t require a large storage tank. Combination boilers are simpler to install than regular boilers since they get their supply of cold water directly from the mains.
We’ve spent hours conducting in-depth market research into hundreds of combi boilers to assist customers in making decisions about their upcoming purchases. This research included analyzing more than 10,000 customer reviews from reputable third-party websites like Trustpilot, Which.co.uk, and The Langley Boilers Guide, looking at the marketing materials of the companies, and assessing numerous independent data sources to help us identify the top combi boilers in the market.
Our suggested manufacturers and installers of boilers
Is a combi boiler electric or gas?
Gas or electricity can be used to power combi boilers. But because gas-powered combi boilers are more widely available, they frequently cost less.
For both larger and smaller residences, Worcester Bosch offers a variety of combination boilers, as well as outdoor boilers that work with gas, oil, and LPG fuel. All come with a standard 10-year warranty. The Greenstar 4000 combi boiler is by far Worcester Bosch’s most popular boiler type. Apart from its modest size, this energetic little boiler has a number of characteristics that make it ideal for small and medium-sized households.
It has a wide power range that can cut down on gas usage and energy costs, and it can run on a 20% hydrogen blend, which means it can run on gas efficiently for the entirety of its lifetime. The Vaillant ecoTec range, which we’ll discuss later, is a good option for purchasers who want to be environmentally conscious but don’t want to fork over the extra money. It has an A rating for energy efficiency and a cutting-edge Quick Tap water-saving feature that will reduce water waste. For purchasers in locations with low water pressure, the Combi Greenstar 4000 is a better option than the Viessman 111-W since it operates well and ensures forceful showers under all circumstances. We adore the peace and quiet, which is especially advantageous if you live in a small house.
The Greenstar 4000 comes in a variety of sizes, including the 25kW and 30kW, and is far more beautiful, quieter, and compact than its predecessor. It has an ErP-rating of 94% A-rated, is compatible with all Worcester Bosch controls and third-party Wi-Fi smart controllers (such as Hive, Nest), and costs a reasonable amount.
Cost
The compact size of the Worcester Bosch Combi Greenstar 4000 makes installation simple (and affordable) without sacrificing quality.
Our suggestion
Although compact, the Worcester Bosch Greenstar 4000 Combi Boiler is incredibly potent. Not only is Worcester Bosch a favorite among consumers, but it has also won the Which? Best Buy Award for more than ten years running. It’s not the most affordable boiler, but in terms of features and cost, it falls exactly in the middle of the 2000 and 8000 series.
The Greenstar 4000 is a hassle-free, low-maintenance combi boiler that has a sizable guarantee and offers simple access through detachable side panels. Parts are easily accessible in the UK because to the Worcester Bosch brand, and customer service is assured. The 25kW combi boiler, which has dimensions of (h) 724mm x (w) 400mm x (d) 310mm and a flow rate of nine liters per minute, is appropriate for apartments and small properties. Additionally, the 4000 range can be used as a system boiler to heat numerous bathrooms and water outlets.
The Greenstar 4000’s appearance is equally stylish, with curved edges, a digital display, and push buttons for operating it. It has built-in wireless connectivity, allowing you to link your boiler to the Bosch EasyControl system (available separately) and use your mobile device to remotely operate the boiler. With a starting retail price of £1,200, this boiler provides excellent value for the money and has the capacity to heat a small apartment or house while fitting neatly inside a tiny closet. Compared to the Ideal Logic+ or Baxi Platinum, it is quieter, sleeker, and more efficient, and it works admirably given the price.
This is by far the finest value for money for small houses when combined with Worcester Bosch’s excellent customer reviews, extensive warranty, and price-matching options.
In 1917, Viessman began as a family-run locksmithing business, but times have since evolved. Today, the brand is associated with high-quality, German-engineered boilers, and in recent years, their recognition and praise in the UK have soared.
The Viessman Vitodens 111-W is a reliable, high-capacity storage combi hybrid that can handle the most rigorous hot water demands of any modern home without the need to purchase an additional hot water storage cylinder, making it an excellent choice if you need a powerful boiler at an affordable price. Even while the Viessman Vitodens 111-W is still significantly larger than models like the Worcester Bosch Greenstar 4000, it still saves a lot of room. It can fill a bath with hot water in eight minutes while simultaneously feeding a washbasin or sink with its flow rate of 18 liters per minute, making it appropriate for most rooms with somewhat higher than average hot water needs.
It’s not exactly compact, but at (h) 950mm x (w) 600mm x (d) 500mm, it’s still small enough to fit discretely in a cabinet or storage area. The Viessman Vitodens 111-W has received overwhelmingly positive ratings, with an average rating of 4.5 out of 5 stars, on websites like Trustpilot and other consumer review sites.
There are two 25kW and 32kW models of the Viessman Vitodens 111-W available, with the 32kW model being slightly larger and better suited for larger homes with additional bathrooms and radiators. Its integrated 46-liter water storage cylinder heats water separately, ensuring steady pressure and water supply while in use. You can operate your boiler remotely using your phone because it works with smart thermostats like Hive, tado, and Nest.
Cost
Given the quality and engineering of their boilers, Viessman has incredibly low prices. The Viessman Vitodens 111-W combi boiler should cost homeowners over £3,000 on average, but a conversion might cost as much as $5,000. It is advisable to get a comprehensive quote before making a choice.
Boiler model number 111-W B1LD-35 from Viessmann
Our suggestion
For homes who require more power than a typical, compact combi boiler can provide, the Vitodens 111-W is an excellent option. The boiler is extremely efficient despite being more powerful, which can significantly lower your energy expenditures (especially if you are replacing an older model).
While the lesser heating output model can still produce 29.6kW of hot water, the 35kW model can cover the heating needs of up to 15 radiators and has a home hot water output of 34kW. This combi boiler is your best option if your home has a high demand for hot water but limited space.
The boiler’s warranty is a standard 5-year warranty that can be extended to a 10-year warranty if installed by a Viessmann Trained Installer. With a modulating ratio of 1:6, decreased energy usage, consistent temperature regulation, and even weather-compensated operation, it is incredibly dependable (if installed with outside temperature sensors).
The second-largest boiler producer in Europe is Vaillant. It was established in Germany in 1874 and is renowned for its cutting-edge, green designs. Combi boilers, system boilers for bigger or older homes, and standard open vent boilers are all produced by the firm. Boilers from Vaillant are frequently contrasted with those from Worcester Bosch, the market leader in the UK, however they have a minor advantage in terms of green technology.
The ecoTec Boiler line was the first to be constructed with materials that are 85% recyclable and safe for the environment. With up to 20 radiators, it is a quality, dependable, high-performance combination boiler that can easily heat big properties.
The Vaillant ecoTEC Green iQ 835 Combi boiler also has a respectable flow rate of 14.5 liters per minute, but it comes with the warning that your home needs sufficient water pressure to operate properly, so homeowners should have their pressure tested before selecting this model.
At 35kW, the output is impressive for a combi boiler, and a 43kW version is available for homes with even higher hot water demands (although it is much less compact). It most closely resembles the Worcester Bosch Greenstar 34CDi Classic, however it is significantly more environmentally friendly and has a higher central output.
Cost
Although the Vaillant ecoTEC Exclusive Green IQ 835 Combi Boiler is inexpensive, installation fees must be considered before making a purchase. For the boiler and installation, the majority of customers may anticipate paying less than £3,000.
Gas boiler Vaillant ecoTEC Exclusive Green IQ 835
Our suggestion
For customers with larger homes and higher hot water demands who still wish to prioritize eco-friendliness and energy efficiency, the Vaillant ecoTEC unique Green iQ 835 Combi is a fantastic alternative.
This is a green and sustainable choice for environmentally aware consumers with to the green IQ technology, 94% efficiency rating, ErP A-rating for heat and hot water, and its extra-condensive stainless steel heat exchanger. Weather adjustment elements, which adjust the water temperature dependent on the outside climate, are another environmentally friendly choice.
While the smart controls optimize and automate your central heating system, the load compensation feature modifies the temperature of the hot water produced based on the temperature of the room. With programs like a holiday program to keep your heating and hot water off while you are away from home and flexible time programs, these features guarantee that boilers always operate at top efficiency.
With the Vaillant vSMART smart thermostat and mobile app, which utilizes machine learning to adjust to your home heating preferences and manage your demands with even better efficiency, the Vaillant ecoTEC 835 combi boiler is compatible. The Vaillant ecoTEC 835 is smaller than normal boilers, like the majority of combi boilers, but not as small as some of the other combi boilers available.
It can fit neatly into a utility room but is too large to fit in a typical kitchen cabinet at 720mm (h) x 440mm (w) x 406mm (d). (The ecoFIT pure combi in the same range is significantly lighter and smaller and has a 35kW output. However, the flow rate is substantially lower.
The Vaillant ecoTEC 835 combi boiler comes with a five-year warranty as standard; however, if you hire an authorized Vaillant installer, the warranty can be extended to ten years. It provides excellent central heating, hot water output, and flow without the environmental compromises found in other boilers of comparable capacity and output. Our research revealed that it is well-liked by larger homes with several occupants and bathrooms, and that service standards are top-notch.
When purchasing a boiler, cost is occasionally the only factor to take into account, but affordable does not always equate to low quality. You can be confident that the Ideal Logic+ combi boiler will provide better value than you anticipated, even if you are purchasing it on a tight budget.
Despite having a significantly lower price than the industry standard, the Ideal Logic+ Combi is made in the UK, has won both the Queen’s Award and the Good Housekeeping Award, and has received overwhelmingly positive online consumer ratings. When you choose an Ideal Logic+ boiler, you unquestionably get greater value for your money.
Even the installation is considerably less expensive than usual. Of course, choosing the less expensive option has its drawbacks, namely a shorter warranty period. Although Ideal Logic+ has a shorter guarantee, they are also industry leaders in terms of performance and technological specifics.
The Logic 24kW boiler, with a flow rate of 9.9 litres per minute, is a reliable entry-level boiler that would be ideal for a flat or smaller house. It is easy to install and comes with a standard control panel that is always visible, making it simple to identify any boiler defects that may arise.
The Ideal Weather Compensation kit and digital thermostats are just a couple of the helpful features that the Ideal Logic+ Combi provides that can help you save money on your energy costs. Additionally, it is accredited by Quiet Mark, so you won’t have to worry about a noisy boiler waking you up in the morning.
Cost
The Ideal Logic+ Combi Boiler line is very reasonably priced. Even the more expensive models in the lineup, such the 38kW Logic Code Combi, are under £1,500.
Logic+ 24 combi boiler from Ideal
Our suggestion
The Ideal Logic+ 24kW combi boilers offer excellent value. The norm lies in Ideal Logic. It is less expensive and has a 2-year warranty.
Despite the relatively slight price difference of £200, we strongly advise choosing the Ideal Logic+ combi boiler from this selection because it has additional features and an extended 7-year warranty. (Consider it to be paying £40 year for the warranty.) The Ideal Logic combi boiler range offers a number of benefits regardless of whatever combi boiler you select.
The unit fits easily into a typical kitchen cupboard because to its small size (h) 700 x (w) 395 x (d) 278 mm, and the Logic+ range’s seven-year guarantee, which covers parts and labor, is equivalent to that of some of the more expensive models on the market. It also has a 94% A-grade ErP certification, making it energy-efficient. The Logic+ 24 is the ideal example of how Ideal can manufacture high-quality boilers at competitive pricing. Despite the fact that it isn’t a particularly powerful combi boiler, it would be adequate for homes with one to three bedrooms and a single bathroom.
Although Baxi manufactures in the UK in locations including Preston, Norwich, and Milton Keynes since 1866, it is a subsidiary of the BDR Thermea Group in the Netherlands. It has operations in more than 70 nations, employs over 6,000 people, and generates €1.7 billion in yearly sales. Additionally, Potterton, Main Heating, Megaflo, and other well-known brands in the UK and Ireland have been acquired by Baxi.
Baxi boilers are on par with Worcester Bosch boilers in terms of quality, but they provide better flue options (and better pricing). A range of parts and labor warranties are offered with Baxi boilers. For instance, the Platinum and 800 Combi series has a 10-year warranty whereas the Baxi 200 Combi has a 3-year warranty. Numerous boilers in the lineup have also received the Energy Saving Trust’s endorsement.
Cost
The brand Baxi Platinum is reasonably priced. The average cost of a Baxi Platinum combi boiler is between £200 and £300 cheaper than the Worcester Bosch counterpart (if materials like flue kits, control systems, and system filters are included in the installation cost). Prices for the 24kW unit start at £850 and rise to £1,250 for the 40kW boiler.
Combination Baxi Platinum range
Our suggestion
The Baxi Platinum Combi Gas boiler is something we advise. The 40kW model is quite affordable (starting at £1,250), offers high outputs, an outstanding 16.4 liters per minute flow, and impressive guarantees. It can run two showers and up to 15 radiators in a single residence.
With strong flow rates, high energy efficiency, and dependable parts, Baxi Platinum Combi Gas boilers are appropriate for a variety of families. Unfortunately, the Platinum range is somewhat hefty if you were planning to install it in your kitchen because it was built with heat output rather than size in mind. The Baxi 624 or 630 are excellent substitutes for smaller properties.
The frost thermostat included in the Baxi Platinum line gives you more installation flexibility. It can be put in low-temperature areas without running the risk of the water inside the hydraulics system freezing, including garages, lofts, and other parts of the house with subzero temperatures. (You must make sure you are following Building Regulations and that the space has enough side clearance to install the boiler.) Baxi has an advantage over the rest when it comes to adaptability, and it compares favorably to some of the other brands on this list in terms of price and output. However, because they provide significantly more functions for the price, Worcester Bosch Greenstar is a better option for simple installs.
How to choose the top combination boilers
It can be challenging to select the best combi boiler. The size of your property and your consumption requirements will be the most crucial factors to take into account. However, most homes may get away with installing a far more compact and cost-effective combi boiler. Larger or older homes might need a system boiler (or normal boiler). The following things need to be taken into account:
1. Heat production
Combi boilers are evaluated based on their heating output, or kilowatt (kW), rating. Generally speaking, you require at least 2kW per radiator; for example, a residence with 10 radiators can utilize a 24kW combi boiler.
Less liquid can be heated every minute, nevertheless, the lower the heating output. To prevent problems in the future, you might wish to get a combi boiler with a higher output if your home has multiple bathrooms and many occupants.
For instance, a four-bedroom home with up to 20 radiators, more than three bathrooms, and more than three showers shouldn’t accept a combi boiler with a wattage of less than 35. When choosing a boiler for a multi-story home, keep in mind that the longer the pipework between the faucet and the boiler, the greater the wait time will be for hot water.
2. The inhabitants’ number
Your boiler’s efficiency may be impacted by the number of bedrooms and people. The demand on your central heating system increases as the size of your home increases.
You will need a larger boiler if numerous residents share bathrooms because there is a higher possibility that simultaneous hot water needs (such taking a shower) will occur. With a smaller combi boiler, using many baths or showers at once will be challenging if you have more than one in your home.
3. The fuel type
The majority of homes in the UK utilize natural gas or mains gas, however a small number of remote structures don’t have access to the gas network and instead use LPG bottles or oil. Your choice of gas boiler may change as a result. The best fuel is LPG, which is also the fuel with the lowest carbon emissions.
4. Power effectiveness
As the boiler can produce more than half of the home’s emissions, environmentally aware buyers must take the boiler’s energy efficiency into account. Your home’s heating costs can rise if your boiler is inefficient and wastes energy. A high-efficiency boiler with an A rating can cost hundreds of pounds annually, especially if you choose one with a reliable heating control system (which allows you to choose which rooms are heated and when). By doing this, you can avoid wasting energy heating empty spaces.
5. Cost
Although much more expensive than standard boilers, combi boilers are still rather expensive. The price of the boiler can be as cheap as £575, but you should always factor in the cost of installation (as well as the price of venting, accessories, and components). These expenses are frequently just as expensive as the boiler itself.
6. Guarantee
Boilers are typically made to last for at least 10 to 15 years. Any interruption to your central heating and hot water supply is unpleasant to deal with, especially in the winter, and a damaged boiler is expensive to fix or replace. When choosing a product, look for warranties that are extensive and lengthy. That way, if something goes wrong as a result of a defective boiler or poor craftsmanship, you have some recourse to promptly and affordably fix the problem.
7. Knowledge
The better, the more time a company has been in operation. A firm can install and construct a high-quality boiler that will last you for years if it has had several years (or better yet, decades) of experience. The majority of the businesses we looked at are supported by at least 20 years of experience.
Why should a combi boiler be installed?
a gas water heater and a boiler. Isolated on a blue background are a home furnace and tank. Combi heating system. White smart gas boiler with control, hot and cold pipes, and burner for heating water Compact Vector Combi boilers are great for saving space. Photo courtesy of Adobe
1. Combi boilers are smaller.
Combination boilers are quite compact when compared to ordinary boilers. Although hybrid types are available, there is no need to store hot water, which saves space and lessens the possibility of your pipes freezing in the winter. Your roof space will be freed up because the typical combi boiler may fit neatly into an airing cupboard or kitchen. They are also more simpler to install and maintain due to their size.
2. Cost-cutting
Combination boilers are quite effective. The majority of the combi boilers mentioned in this article are more than 90% A+ efficient, which makes heating your home very economical. Traditional boilers use a significant amount of energy to heat large volumes of water, whether you are taking a shower or just washing your hands. Much less water needs to be heated with combi boilers. The majority of contemporary combi boilers also come with sophisticated temperature controls that let you select which rooms to heat and when.
3. Quick hot water access
There is no need to wait for the water to heat up because combi-boilers heat water as it is needed. Because there is no chance of running out of hot water, using a combi boiler is much more enjoyable (as does waiting in line to use the restroom). Some of the more potent combi boilers available today can heat residences with numerous bathrooms and people, permanently resolving the hot water problem.
Conclusion
A combi boiler shouldn’t be selected for your home based just on speculation. In order to identify the top combi boilers available on the market that meet consumer expectations, we gathered research for hundreds of hours.
The market leader Worcester Bosch offers a variety of outstanding, dependable combination boilers with extensive warranties, at reasonable costs. There are many things to choose from, a superb reputation for the brand, and positive client feedback. For smaller homes, it undoubtedly has the most appealing compact boiler, particularly the Worcester Bosch Combi Greenster 4000. Despite not having the most affordable items on the market, Worcester Bosch delivers real value for the money, and customers will enjoy using their Worcester Bosch boiler for many years without any hassles. Even if the boiler is modest, the outputs and waterflow are excellent, and the model still uses very little energy.
The Viessman Vitodens 111-W Storage Combi Boiler is a better choice for people with larger homes, several residents, and multiple bathrooms that will be utilized at once. This hybrid combi boiler has a tremendous wattage and water flow, a high energy efficiency rating, and a dedicated hot water storage unit. These German-engineered products are well-known for being of a high caliber and coming with extensive warranties.
Consider the Vaillant ecoTec unique Green iQ Combi Boiler if you’re worried about your carbon footprint and energy efficiency. Environmental friendliness has been a priority for Vaillant in terms of both design, features, and the materials employed. Homeowners who choose this brand can feel secure knowing that their boiler will be long-lasting, quiet, cost-effective, and almost entirely recyclable when its life cycle is complete.
The Ideal Logic+ Combination Boiler is a terrific option for consumers on a budget if money is their main concern. It has excellent quality, a strong 7-year warranty, and a low price. Additionally, these boilers are energy-efficient enough to significantly lower your electricity bills, extending your cost savings over time. The Baxi Platinum Combi Boiler provides the versatility you require if you need to install your boiler in a tiny space that is prone to subzero temperatures.
Before making a purchase, it’s crucial to speak with a professional installation even though each of these top brands provides quality and value for the money. The improper wattage, size, or type may cause even the best-reviewed combi boiler to fail.