What are the best gas boilers models to buy in 2023?
If you’re in the position where you are looking for a replacement boiler, or maybe you fancy a new, swanky modern one, but you’re unsure what gas boiler to go for, this blog is will give you a help in hand. We will be looking at the top 3 combi, system and regular on the market in 2023, helping you choose the perfect new gas boiler for your home.
Before we get into the nitty-gritty, you may be reading this thinking, ‘I don’t even know what kind I have’. If this is the case, don’t panic, we have a separate blog that discusses in detail, the different boiler types, to help you identify which one you have so that you can pop this information into our survey and be ready to choose your new one!
However, to put it simply, here are the different boilers types that WarmZilla offer:
Combi Boilers
Combi’s, or to give them their full title, combination boilers, are the most common type of boilers found and installed in the UK. In fact, over 70% of all installs in the UK are combis. The name combination boiler comes from their ability to both heat your home and provide you with hot water.
Combi’s are connected directly to the mains water supply coming into your home. They heat this water directly, eradicating the need for a separate water tank (as with a system or regular type boiler). This saves a great deal of space, especially in flats and smaller homes where space is limited.
Another benefit of a combi is that they supply hot water at mains pressure, which allows you to enjoy mains pressure showers without needing to install a shower pump.
Combi’s keep a small reservoir of pre-heated water within them to ensure they can supply hot water to taps instantly. Head over to our ‘how do combi boilers work’ blog for more details. For more information on how combi boilers work, head over this our blog.
System Boilers
A system boiler can usually be found in homes that have a high requirement for hot water. They work by heating water in a separate storage tank from the boiler, usually found in an airing cupboard, this hot water is then available for use in multiple bathrooms should it be required. In practice, you can have two baths running in separate bathrooms and they will both get hot water without affecting the heating of your home.
This differs from a combi, as a combi heats water directly from the mains supply and doesn’t store hot water, so you may struggle to run two baths simultaneously. Click the link if you want to know how system boilers work in detail?
Regular Boiler
Regular systems, also known as conventional, traditional, heat only or open-vent boilers, are the most difficult to install or replace. A regular includes both a hot and cold water storage tank, the boiler itself, and an expansion cistern located next to the cold water tank. This takes up quite a bit of space in a home and it’s usually preferable to switch to a combi so that these tanks can be removed.
Similar to system boilers, regulars are able to supply large amounts of hot water simultaneously to multiple bathrooms due to the hot water storage tank facility. Want to know more about how regular boilers work? You guessed it. We have a blog that covers this, so head on over!
Best Combi Boilers in 2023
Worcester Bosch Greenstar 4000 Combi Gas Boiler Range

The best energy-efficient boiler on the market in 2023 is the Worcester Bosch Greenstar 4000.
The Worcester Bosch Greenstar 4000 combi is available in two kW outputs. These include a 25kW model and a 30kW model.
The new Greenstar 4000 range is Worcester Bosch’s latest edition to the family and will be replacing the Greenstar i combi range. It sits neatly in between the Worcester Bosch 2000 and the Worcester Bosch 8000 Life and Style range.
The Worcester Bosch Greenstar 4000 is one of the most efficient combi boilers on the market, with an efficiency of 94% and an ErP A-rating.
The Energy Saving Trust said: “Heating and hot water accounts for over half of what you spend in a year on energy bills, so an efficient boiler makes a big difference.”
The boiler energy efficiency depends on a number of factors such as whether your boiler is a condensing or non-condensing unit, the age of your boiler, whether your boiler’s kW size is compatible with your homes needs, how many people are using the heating system at once, and plenty of other factors.
Worcester Bosch is one of the best brands on the market. Known for their reliable boilers, outstanding build quality, sleek designs and long warranties. Worcester Bosch currently holds the Royal Warrant to supply heating to the Royal Family and has won the Which? Best Buy Award for their range of boilers for the last ten years.
This prestigious award recognises the companies and individuals that consistently get it right for their customers. The Which? Boiler Brand Award is judged on reliability, build quality, recommendation, and customer score. During the 2021 survey, Worcester Bosch scored a huge 84% and ranked in 1st place.
The Ideal Logic Max Combi Gas Boiler Range

The Ideal Logic Max combi boiler range is Ideal’s more premium boiler. It has all of the amazing features and benefits that you get with the Ideal Logic Plus range but with some added extras.
Based on their award-winning Ideal Logic Plus range, the Ideal Logic Max is the best of the best. This boiler range comes with an amazing 10-year parts and labour warranty as long as your warranty is registered within 30-days of installation. When buying a new boiler with us, we’ll register the warranty for you!
The Ideal Logic Max combi boiler range is available in kW outputs of 24kW, 30kW and 35kW, perfect for small to medium-sized homes with moderate demand for central heating and instant hot water. With such a large range of combination boilers to choose from, there is a boiler suitable for every home.
During the Which? Best Boiler Survey in 2021, 8,001 members of the public were asked to rate Ideal Heating as a brand. The ideal was awarded an overall brand score of 74% and ranked 5th place out of the 16 boiler brands that were scored.
Vaillant EcoTec Pro Combi Gas Boiler Range

The Vaillant EcoTec Pro is known as the smart combination boiler for small to medium homes. Three combi models cover 24kW, 28kW, and 30kW heating outputs. A flow rate of up to 12.3 litres per min for fast instant hot water.
Vaillant is a great boiler brand. Vaillant offers reliable boilers at a reasonable price. With an average rating of 4.6 out of 5 on Trustpilot from over 14k reviews, you know that you are dealing with a good company that cares about its customers.
The Vaillant boiler range has been given a Which? Best Buy award and they have also been awarded a Quiet Mark Accreditation, from the Noise Abatement Society for their quiet running boilers.
During the Which? Boiler Brand 2021 survey, Vaillant boiler ranked 4th place, showing us how loved they are as a brand as well as how reliable their boiler models are!
Now we’ve covered the best combi boilers on the market this year, let’s look at the best system boilers!
Best System Boilers in 2023
Worcester Bosch Greenstar 8000 Style Gas System Boiler Range

The Worcester Bosch Greenstar 8000 Style system boiler is available as a 30kW and 35kW model.
It is important to remember that when purchasing a new or replacement system boiler, you will need the additional space in your home for the hot water cylinder tanks. This is typically installed inside an airing cupboard or a similar-sized space in your home.
As mentioned, the Worcester Bosch Greenstar 8000 Style range is available in two high-gloss colours, black and white, so you have a choice of model to fit perfectly with your home. This system boiler range comes with a 10-year guarantee, an easy-to-use, full-colour boiler display as well as the ability to run on a 20% hydrogen blend.
With this said, there is a lot of controversy around the future of the heating industry. If you would like to learn more about where we believe the direction that the heating industry is heading, we have a separate blog where we talk all about the recent updates.
Ideal Logic Plus Gas System Boiler Range

The Ideal Logic Plus range is known for being Ideal’s middle-of-the-range boilers when it comes to price, however, this does not reflect the quality of the boilers. Supported by the Queen’s Award for Enterprise 2013 and the Good Housekeeping Reader Recommended Status in 2013 and 2017, the Ideal Logic Plus range is another highly reliable and efficient boiler range.
Similarly to the Ideal Logic Max, the Ideal Logic Plus or Logic+ as you may see its name displayed, is available as a combi (combination) boiler, a system boiler, and a regular boiler, meaning that there is a model that is ‘ideal’ for everyone (excuse the pun!)
The Ideal Logic Plus system range includes the Ideal Logic Plus 15kW, 18kW, 24kW, and the 30kW). When you purchase a new Ideal Logic Plus boiler with WarmZilla, you will receive an impressive 8 years warranty.
Vaillant EcoTec Plus System Gas Boiler Range

Vaillant’s most flexible system boiler for any home. Six system boiler models covering 12kW, 15kW, 18kW, 24kW, 30kW, and 37kW heating outputs mean this boiler is suitable for anything from small flats to large homes.
It is important to remember that when purchasing a new or replacement system boiler, you will need to ensure that you have the room in your home for an additional hot water cylinder, which is usually installed in an airing cupboard. Although system boilers take up more room in your home, they are ideal for those that require hot water ‘on-tap’ (excuse the pun!).
The Vaillant EcoTec Plus System boiler has a compact design, however, with the addition of a hot water storage tank, this system boiler is great for larger homes. Thanks to its efficiency rating of 94%, this system boiler can help to lower your running costs.
Time to move on to the best regular boilers on the market this year…
Best Regular Boilers in 2023
Worcester Bosch Greenstar Ri Regular Gas Boiler Range

The Worcester Bosch Greenstar Ri gas boiler is available in a wide range of kW options, suitable for all property sizes. This range includes a 12kW model, a 15kW, 18kW, 21kW, 24kW, 27kW and a 30kW boiler model.
The Worcester Bosch Greenstar Ri Regular Gas Boiler range is a compact, lightweight boiler that can fit easily inside a standard kitchen cupboard. This model is fitted with simple boiler controls, built-in frost protection, a choice of controls and a 10-year warranty when purchased with WarmZilla.
Ideal Logic Heat Regular Gas Boiler Range

The Ideal Logic Heat boiler range is known as Ideal’s budget-friendly regular boiler. This boiler is the least expensive of the Ideal boiler ranges, however, they are still known to be a reliable and robust boiler model.
The low-lift weight of 22.7kg and its compact size makes installation quick and easy, allowing the boiler unit to be fitted easily into your standard kitchen cupboard, out of sight, out of mind. With a highly efficient rating of 93% and ErP A-rating, the Ideal Logic Heat regular boiler range could also potentially help to lower your bills and carbon footprint.
There is 12kW, 15kW, 18kW, 24kW and 30kW in the regular boiler range. The Ideal Logic range comes with a standard warranty of only 2 years, however, when purchasing a new or replacement Ideal Logic boiler with WarmZilla, you will receive an 8-year warranty with your boiler.
Although the Ideal Logic is known for being a budget-friendly boiler, they are well-known and loved for their low-lift weight and compact design, which is ideal for an easy installation. They are also designed to have a scratch-resistant casing and an LCD display screen for easy use. The Ideal Logic regular boiler range also comes with built-in frost protection for extra peace of mind.
Vaillant EcoFit Pure Regular Gas Boiler Range

The cupboard-size regular boiler for any home. Six regular models covering 12kW, 15kW, 18kW, 25kW, 30kW, and 35kW heating outputs.
Vaillant EcoFit Pure is a highly efficient and reliable regular gas boiler, with an efficiency rating of 94% and an ErP A-rating for heat means that you could save money on your heating bills.
The Vaillant EcoFit Pure Regular boiler range is fitted with built-in frost protection, easy to use controls and an automatic temperature setter.
Regular boilers are ideal for homes with a high demand for instant hot water. This is because they are designed to work alongside an additional hot water cylinder and cold water tank, which are kept in an airing cupboard and (usually) the attic of your home. Coldwater is heated and then stored inside the cylinder at optimum temperature, ready for when you need it.
However, regular boilers are not recommended for smaller homes with limited space because they require additional hot and cold water tanks.
We hope our best boiler guide of 2023 has been of help in your quest for the perfect boiler, if you have any questions just use our live chat or email us at ask@warmzilla.co.uk, we’re always happy to help.
If you’d like to get an instant fixed price quote on a new boiler suitable for your home, then take our survey now, it only takes a couple of minutes and you’ll have an idea of how much a new boiler will cost you.