Best Combi Boiler Plus 5 Best Boilers For Reliability & Efficiency

Best combi boiler review for 2023 plus the top 5 best boilers to buy right now

Getting the best combi boiler for your home is essential for a warm and happy home.

This guide shows you the top 5 best boilers to buy right now that are energy efficient reliable, and of course the most important thing, value for money.

There are many factors to consider when deciding on which combi boiler is best for you, including the size of your home, your hot water demand, needs (patience if you want a quick bath), and of course your budget.

All these factors are taken into consideration in our review and are verified by our customers and Gas Safe installers, with pros, cons and prices you can expect to pay.

Get a fixed online price on the best combi boiler in 20 seconds – Click here >

Best combi boiler 2023: What we did and how we did it

A little brag here, but Boiler Central installs thousands of combi boilers exclusively with 12 years warranty, so we can advise you on the best boilers currently available for your property and keep our list updated as and when we believe newer and better boilers are available.

When it comes to the best combination boilers, some people already have a clear idea of what they want, so if you have a particular boiler manufacturer in mind, you can find our top pick from their selection of new combi boiler options.

As Boiler Central is a Gas Safe registered installation company, we install thousands of boilers each year at Boiler Central, so we get to see what our customers like and dislike.

Not only that, but because we sell the entire market range of boilers, we sell all brands, not just certain ones, and finding the best combi boiler at the best price is what everyone wants, so let’s go get them.

Our best combi boiler review checklist:

To find out the best combi boilers we take into account:

• Boiler Central combi boiler sales
• Customer surveys
• Boiler specifications
• Most energy-efficient combi boiler
• Most reliable combi boiler
• Warranty length – manufacturers trust
• Issues raised which are logged weekly
• Price of the boiler
• Aftercare from the manufacturer
• Manufacturer online reviews
• Google My Business reviews
• Trust Pilot reviews
• Which? Best Buys

Is that list long enough for you? Well here’s what happened when we put it to the test:

So, how did we come to the final decision on the best combi boiler?

All of the factors listed above are important considerations when selecting the best gas combi boilers on the market and selling thousands of these boilers every year certainly helps us become experts in the field.

You can be sure that we will always recommend the best boiler for your home and never oversell.

This best gas boiler guide is extremely helpful because most homes in the UK have a combi boiler because the typical home has three bedrooms and one or two bathrooms, which is ideal for the combi.

We have a list of the top boiler manufacturers below, listed in order of rating, in case the best combi boilers in our list are not sufficient.

We hope this review will help you choose the best boiler for your home.

If you need assistance or have questions, contact one of our experts at Boiler Central, who can offer advice.

What are the best gas boilers on the market?

What you may decide as the best, we might decide as something entirely different. However, we have tried, used and tested all these boilers we think, are the best boilers on the market.

We as boiler experts have gathered years of experience to put together a ranking of the best combi boilers.

It’s no suprise that most people want the best, who doesn’t. The mid-range combi boiler market has to easily be the most competitive, unreliability is not an option for these lot

The top 5 best combi boilers chosen by our experts in 2023 are:

Here is our list of the best combi boilers, which are fortunately currently available to buy online.

At the top of the list is the German-engineered Viessmann Vitodens 050 combi boiler, which has taken over from the Worcester Bosch 4000.

Over the past year, we have seen a huge spike in sales for the fantastic Viessmann Vitodens 050-w due to the fact it uses a better stainless steel heat exchanger making it the most reliable combi boiler and is still an amazing price.

Combi Boiler Ranking	Boiler Make & Model
1st	Viessmann Vitodens 050
2nd	Worcester Bosch Greenstar 4000
3rd	Worcester Bosch Greenstar 2000
4th	Ideal logic C30
5th	Viessmann Vitodens 100-w

#1 Best combi boiler – Viessmann Vitodens 050-w

The Viessmann Vitodens 050-w combi boiler is one of the best combi boilers we have encountered, it is utterly reliable, hydrogen ready to 20% and being German made you can be sure that there will be years of hassle-free heating.

The Viessmann Vitodens 050 uses a stainless steel heat exchanger which is far superior to the other boilers that use aluminium in this list and will last much longer and be more reliable – everything you want in a boiler.

The Viessmann Vitodens 050-w combi boiler is available in 25kw and 30kw, and the 30kw has been selling very quickly and is now ahead of the latest Worcester 4000 boiler since its release last year

The Vitodens 050 is also not the most expensive boiler either in terms of mid range combi boilers, coming in less than its main competitors.

Small and compact in size, and very quiet, this Viessmann combi boiler is perfect for kitchen cupboards and comes with a 10-year warranty from Viessmann or 12 years with Boiler Central.

If this isn’t enough Viessmann is rated excellent on Trustpilot reviews, along with having an over 98% reliability rating. The numbers just add up for this comb boiler.

The following are just some of the quality features that the Viessmann Vitodens 050-W 30kW combi boiler has:

Viessmann Vitodens 050-w	BOKA
Boiler Type	Gas Combi Boiler
Which Recommended?	Yes
Boiler Warranty	10-year Viessmann warranty (12 with Boiler Central)
Output	3.2kw to 32kw
Energy Rating	A-Rated
Instant Hot Water	Yes
Boiler Controls	Wireless heating controls
Smart Thermostat Compatible	Yes
Boiler Filter	Yes – completely free
System Cleanse	Yes – completely free
Compact Design	Yes

One of the best things about the Viessmann Vitodens 050-w combi is the price. You can see the latest Vitodens 050-w as a standalone boiler or you can get the full cost of this combi boiler including installation online now with Boiler Central. 

Get a fixed quote in 20 seconds on a Viessmann Vitodens 050-w combi boiler: Click here

#2 Best combi boiler – Worcester Bosch Greenstar 4000

The Worcester Bosch Greenstar range is the legendary boiler range that everyone has heard of. There is a good reason for it too.

This Worcester Bosch combi boiler is exceptional at what it does at the right price. Hydrogen blend ready, Which recommended and now with a Quite Mark rating for low noise output.

It really is an improvement on what was a dominant boiler.

Reliable, and easy to use with its touchscreen LCD display, this mid-range boiler which is replacing the old Greenstar i range is in most people’s price range.

It’s not the cheapest combi boiler you can buy, but for that extra £100 or so you can get a whole lot more boiler and a 10-year warranty.

The Worcester Bosch 4000 combi boiler range is available in different outputs, but we believe the 30kw is the one to be getting installed.

Just the right amount of power coupled with high efficiency and hassle-free heating – all backed up with a huge 10-year Worcester boiler warranty as standard – You can get 12 years with Boiler Central!

If you are looking at buying this combi then you can see the latest Worcester 4000 boiler prices online for a unit on its own, or you can get the full Gas Safe boiler installation price online now with Boiler Central.

Get a fixed quote in 20 seconds on a Worcester Bosch 4000 boiler: Click here

#3 Best combi boiler – Worcester Bosch Greenstar 2000

Worcester Bosch has been hailed as the market leader and for a good reason, they have produced some of the best new combi boiler options for years.

They have consistently produced the best boilers in the UK, and quality products which is why they definitely rank among the best combi boiler manufacturer in 2023.

They have won the Which? award for a few of their boilers, giving you more reasons to purchase a Worcester for your boiler installation.

So let’s look at their first budget boiler. The Worcester 2000 combi boiler.

The Worcester Greenstar 2000 combi boiler is a great choice for small to medium sized homes with 1 bathroom.

The Worcester Bosch Greenstar 2000 is one of their best offerings because it offers the following amazing functionality all at a very low price for a Worcester Bosch.

With hydrogen-ready to 20% blend capabilities and a compact design, this combi boiler is a great low-cost heating solution.

• Reduced usage and wastage of electricity
• Has Which? best combi boiler recommendation
• Protection against frost – if fixed outdoors
• Simple controls for users
• Instant hot water

Boiler Type	Gas Combi Boiler
Which Recommended?	Yes for 2021
Boiler Warranty	6-year warranty (8 with Boiler Central only)
Output	30kw
Energy Rating	A-Rated
Boiler Controls	Wireless heating controls
Smart Thermostat Compatible	Yes
Boiler Filter	Yes – completely free
System Cleanse	Yes – completely free

These are some of the main reasons that make this unit so popular as well the low cost. See how much a Worcester 2000 combi boiler costs online for more information or get the full cost of the boiler and installation online now with Boiler Central.

Get a fixed quote in 20 seconds on a Worcester 2000 boiler: Click here

#4 Best combi boiler – Ideal Logic C30

Ideal is another brand that is trusted for the quality of their boilers and judged on their affordability. If you are searching for the best boilers in 2023, you should look at the collection that Ideal boilers have available.

Now Hydrogen ready to 20%, the Ideal Logic combi boiler is the choice of new-build developers across the country and the most installed boiler in the UK. The Ideal logic is super compact, easy to install, easy to use, and best of all comes with a great price tag.

Rave reviews from customers on top websites such as the Ideal Trustpilot review page only help its cause and this simple boiler is simply great at just getting on with the job with a minimum of fuss.

When you get the Ideal Logic C30 combi boiler, you will enjoy the following features:

• Compact in size, extremely easy to use
• Winner of Good House Keeping awards – 2013 and 2017
• 10-year Ideal boiler warranty

Boiler Type	Gas Combi Boiler
Which Recommended?	No
Boiler Warranty	10-year warranty
Output	30kw
Energy Rating	A-Rated
Boiler Controls	Wireless heating controls
Smart Thermostat Compatible	Yes
Boiler Filter	Yes – completely free
System Cleanse	Yes – completely free

The Ideal Logic is great value for money, it is like a Toyota car, it is just a good boiler, nothing too fancy or flashy, hence the great price too. See the latest Ideal Logic combi boiler for a unit on its own, or get a fixed price quote for Gas Safe boiler installation with Boiler Central.

Get a fixed quote in 20 seconds on an Ideal boiler: Click here

#5 Best combi boiler – Viessmann Vitodens 100-W

The new Viessmann Vitodens 100-W is another brand that is trusted for the quality of their combi boilers and judged on their affordability.

If you are searching for the best boilers in 2023, you should look at the collection they have available. The new Vitodens 100-W is hydrogen ready to 20%, has built-in WiFi and is packed with power.

The Viessmann Vitodens 100-w is one of the best-selling combi boilers in Europe and comes with relentless reliability and power.

This Vitodens 100-w 30kw combi boiler is perfect for small to medium-sized homes.

If you need some extra power due to high hot water demand, the Vitodens 100-w 35kw is the perfect Viessmann combi boiler for medium-sized homes with 2 bathrooms.

When you get the Viessmann Vitodens 100-W, you will enjoy the following features:

• Future proof boiler with new technologies
• Hydrogen ready (20%)
• Built in Wifi
• Extremely easy to use
• Which Recommended best buy in 2019
• 10-year warranty – 12-years with Boiler Central*
• Sublime German engineering
• Superb value for money
• A powerful boiler for less

Boiler Type	Gas Combi Boiler
Hydrogen Ready (20%)	Yes
Built In Wifi	Yes
Which Recommended?	Yes in 2021
Boiler Warranty	10-year warranty
Output	30kw
Energy Rating	A-Rated
Boiler Controls	Wireless heating controls
Smart Thermostat Compatible	Yes
Boiler Filter	Yes – completely free
System Cleanse	Yes – completely free

Get a fixed quote in 20 seconds on a Viessmann Vitodens 100-W boiler: Click here

Top 6 combi boiler brands & manufacturers

#1. Viessmann
#2. Worcester Bosch
#3. Ideal
#4. Baxi
#5. Vaillant
#6. Glow Worm

If you’re older, you probably recognise the majority of these combi boiler brands, but if you want to learn more about these different makes of combi boilers, visit our page on the best boiler brands.

Change is good, and change is almost always for the better. Our list of suggested best gas boilers will undergo a significant overhaul in the first half of 2022, with the Baxi 600 and Vokera EasiHeat dropping out of the top 5 spots.

All of the models that will be available in 2023 are combi boilers that are 20% hydrogen ready boilers.

The Ideal Logic, which is also prepared for hydrogen to 20%, joins the Viessmann Vitodens 050-w and Vitodens 100-w in being hydrogen blend ready and ready for hydrogen up to 20%.

The best boiler for your house is one that can handle 20% hydrogen so that you’ll be prepared for any future transition to hydrogen blends.

Is it reliable? Is it energy efficieint? Does it fit in a cupboard? How longs the warranty? Yes, Yes, Yes & nothing less than 12 years is acceptable

Best boilers according to facts and figures

So you’re on the market for a replacement combi boiler?

But, before we tell you how we arrived at our recommendations for the best boilers, let us first provide you with some interesting statistics and quick summaries.

Statistics and boilers are both tedious, but as the saying goes, knowledge is power.

Feel free to investigate, but we do know a thing or two about combi boilers, accounting for over 80% of all sales at Boiler Central.

Boiler Type	% sales 2022
Combi boiler	81%
System boiler	16%
Regular boiler	3%

A breakdown of combi boilers sold in 2022

We can also break this down even further to each specific combi boiler in terms of the percentage sold of each boiler. This also helped us in making the decision and shows that the Viessmann Vitodens 050-w combi is still well ahead of the rest in terms of sales.

Combi boiler	% Sales 2022
Viessmann Vitodens 050-w	38%
Worcester Bosch 4000	28%
Worcester Bosch 2000	10%
Ideal Logic C30	9%
Viessmann Vitodens 100-w	14%
other combi boilers	1%

Best central heating boilers

We have all heard of Which? Best Buys right? and they have no stone left unturned when looking for the best central heating boilers.

Which? is the leading consumer powerhouse that tries, tests, and reviews a whole range of products and services available on the market, including combi boilers.

They then come up with the top picks and tell us all what is the best domestic gas boiler to buy for central heating to power a certain amount of radiators. Basically, the more radiators you have the more powerful a combi boiler you will require. See our table below for a guide of what output you require for the number of radiators in your central heating system.

Combi boiler size	Amount of radiators
24kw – 28kw	1-6
29kw – 34kw	7-11
35kw – 40kw	12-18
41kw and over	19+

Which is the best buy combi boiler?

The best buy combi boiler is the Vitodens 050-w in terms of value and price and has been given accreditation for best buy gas boilers in September 2022 by Which.

Which? Also feature central heating boilers and provides its boiler options, of which (excuse the pun), the Worcester Bosch Greenstar 8000 combi boiler is the best buy boiler they have chosen.

There are also others on the list such as the Vitodens 050 & Vitodens 100-w which we think are the best combi boilers to buy.

So, with both Boiler Central and Which? claiming the Worcester 8000 is the combi boiler to buy this year, why not get a fixed price on this exact boiler now?

Click here to get an online price in 20 seconds on the Worcester Bosch Greenstar 8000 combi boiler.

In 2021, the combi boiler market drastically changed. Wifi, hydrogen ready to 20%, intelligent filling systems, and facelifts were all the rage. Are boilers becoming cool?

Best new combi boiler to buy this year: Summary

We’re here to tell you about the best combi and system boilers available for purchase in the UK, and after conducting extensive research and reviewing thousands of online reviews, we’ve put together a rigorous benchmark system to find the best available heating and hot water boiler systems on the market today.

We have done the hard work for you by ticking off every box on the checklist to ensure optimum flow rates and water pressure, hot radiators, energy-efficient heating and years of no boiler repairs or breakdowns along the way.

The best combi boiler to buy – Our verdict

Our aim for this guide is to give you an idea of the best boilers on the market for this year so that you can make a decision based on facts.

We also want to show available options from boiler manufacturers and the types of boilers on the market in 2023.

Again, if your boiler is getting old, say 8 to 10 years old, and gas bills are starting to creep up then you may want to consider upgrading.

How much are the best combi boilers?

If you are looking for the best combi boiler, then you also want the best combi boiler installation to go with it to ensure that your boiler works for the duration of its lifetime.

A new combi boiler installation costs around £2,200 for a replacement, or up to £4,000 if you are changing to a combi boiler from a boiler with a tank or back boiler unit. Here are the latest prices of the combi boilers in our review:

Gas combi boiler	Installation Cost
Viessmann Vitodens 050-w	£2,295
Worcester Bosch Greenstar 4000 30kw	£2,345
Worcester Bosch Greenstar 2000 25kw	£2,250
Ideal Logic C30	£2,320
Viessmann Vitodens 100-w	£2,550

Is it worth spending more on the best combi boiler?

Getting a boiler replacement and new boilers isn’t just about how much a combi boiler costs and which boilers have the best specs, so check out our handy list of the top combi boilers on the market right now, complete with our feedback and no confusing jargon.

With our extensive review process, we rigorously test each boiler, ensuring that we check everything from the energy usage to the output and flow rate.

Most importantly, consider how dependable the combi boiler is, as well as the design, ease of use, and longevity.

Customer feedback is one of the best ways for us to rank our top pick combi boilers, which helps us decide which boilers to rank first.

We will then consider the costs associated with each combi boiler; we understand that not everyone prefers an all-singing, all-dancing combi boiler, so our ranking decisions will account for everyone’s budget.

If you want a boiler on finance, Boiler Central has you covered.

Best boilers: listed for your convenience

These are the top picks for the best combi boilers in 2021, 2022 and 2023

The list is also by no means a complete collection of all the boilers you can find in the market as there are still brands like Baxi boilers that make excellent combi boilers or Glow Worm boilers that used to be high on the list.

Vaillant boilers are also another huge german boiler brand that hasn’t made the top 5 combi boiler list, but this is because they tend to be more expensive but offer nothing more in terms of value.

Again, we have judged the above best combi boilers by metrics of performance, price, warranty, easy boiler installation, and maintenance.

You might have seen most of these brand names in 2018 and 2017 too, but that’s because these brands are renowned for consistently crafting amazing boilers.

Buying a boiler from any of the brands listed above also ensures that even if you don’t pick the models recommended here, you can still walk away with a boiler that will work efficiently and diligently for years to come.

For boiler information or a quote – click here

The best gas combi boilers are efficient and reliable

Getting the best gas combi boiler ensures that you have one that is efficient and durable to ensure smooth heating of your home.

It keeps your central heating system ticking over at the perfect temperature with hot water available as and when you need it.

With huge competition in the boiler market, you need to make sure you take your time in order to get the best deal you can on your new boiler, therefore if you think your boiler is not working or on its way out, then you should definitely start doing your homework just in case, and that’s probably why you’re reading this article!

Which is the most reliable combi boiler?

The most reliable combi boiler is the Viessmann Vitodens 100-w, which according to Viessmann has a 98.9% reliability rating.

To make things easier or harder depending on how you look at it, we’re going to be listing down some of the best new combi boilers in 2023 of which are the most reliable combi boilers.

The following are our top 5 boilers picks in terms of reliability, value, performance and efficiency with the winner which I’m sure you can guess is the Vitodens 100-w offering a whopping 98.9% reliability rating.

A well looked after combi boiler could last up to 20 years, it’s not undheard of. It may only be 70% efficient but you 100% got your moneys worth

 Which size combi boiler is best for my home?

When you are taking a look at our top picks for the best range of combi boilers, always make sure to consider how they will perform in your household.

Picking a new boiler that others recommend without considering its performance can be a recipe for disaster.

Instead of just picking the top rated combi boilers, make sure that you pay attention to various factors, including the ones outlined below:

• Where is the boiler going to be placed? (Indoors or outdoors)
• How big are the house and what size boiler should you get for your home? – Larger houses will benefit from boilers that have a larger kW capacity
• What is the water consumption of the house? – If every family member loves a hot bath, make sure you pick a highly efficient boiler that can accommodate this.

By focusing on these major areas, you will be able to find the answer to which boiler manufacturer is best to buy right now. If you are unsure, read our how does a combi boiler work post now. 

What are the recommended gas boilers available in the UK?

So, we have covered which combi and system boilers top the rankings, but are these the most suitable to heat homes in the UK? A quick answer is yes!

The UK has average temperatures which do not often even in the deepest of winters fall below minus 10 degrees; therefore, the power required is not as much as in a country that has much lower temperatures.

When it comes to boiler testing and best boiler recommendations, Which? are the best known for reviewing many consumer products and boiler reviews are high on their list? 

They showcase the leading boilers on the market each year and feature rigorous testing to come up with a final best buy boiler.

 

Frequently Asked Questions

What is a combi boiler & what makes them so good?

You’ll see plenty of combi boilers in the UK market, but if you don’t know what or who the boiler companies are, you might dismiss them.

A combi boiler is a combination boiler that works your indoor central heating system and hot water in one whole unit without the need for a cylinder to store hot water, and most combi boilers are super-compact, of which many can be easily be stored in a kitchen cupboard as long as it is on an outside wall so that the boiler flue can be fitted properly through the wall

This means that you’re able to kill two birds with one stone here. Combi boilers also have a high energy efficiency rating of 98% when it comes to heating water.

How does this benefit you? By saving more money on energy bills and having hot water as and when you need it. Oh, and a toasty warm house!

All this by just getting a brand new energy-efficient combi boiler installed in your home.

For boiler information or a quote – click here

What is a modulating combi boiler?

The best combi boilers, all have boiler modulation. Boilers with modulation will save you money and use less energy.

They reduce energy use because they keep the same temperature throughout their use cycle.

Simply put, boiler modulation lowers boiler output to a lower ratio for example 1:8 when less energy is needed to generate the desired amount of heat.

Which is the most reliable combi boiler?

The most reliable combi boiler is the Viessmann Vitodens 100-w, which according to Viessmann has a 98.9% reliability rating.

To make things easier or harder depending on how you look at it, we’re going to be listing down some of the best new combi boilers in 2023 of which are the most reliable combi boilers.

The following are our top 5 boilers picks in terms of reliability, value, performance and efficiency with the winner which I’m sure you can guess is the Vitodens 100-w offering a whopping 98.9% reliability rating.

How does a combi boiler work?

A combi boiler works by getting up cold water from the mains supply using a heat exchanger. There are 2 separate heat exchangers, a primary one and a secondary one.

One is for the central heating which circulates continuously around your home when switched on and one is for the clean hot water that comes out of your taps and showers.

The combi boiler will heat water instantly when there is demand from either your central heating thermostat or you turn on your taps or showers. 

Find out more about showers and combi boilers here.  

What is the best combi boiler for a 2 bedroom house?

The best combi boiler for a 2 bedroom house is the Viessmann Vitodens 050-w as it is the perfect output for homes with 2 bedrooms and one bathroom.

Not only that, this combi boiler is designed to fit in kitchen cupboards and leave some space, so if you are looking for a boiler for a flat, 2 bed terrace or even a small 3 bed then choose the Vitodens 050 25kw combi! 

What is the best combi boiler for a 3 bedroom house?

The best combi boiler for a 3 bedroom house is the Worcester Bosch 4000 30kw.

This is the ideal output for this type of home with up to 2 bathrooms and reasonable hot water demands.

The Vitodens 050-w came close but everyone loves the Worcester 4000 combi and it while it is slightly larger than most compact versions, it can still be slotted into a kitchen cupboard, we just suggest that you measure up first! 

What is the best combi boiler for a 4 bedroom house?

The best combi boiler for a 4-bed house is the Worcester Bosch Style 8000 35kW combi boiler.

This powerful combi comes in higher outputs than most boilers with outputs of up to 50kw.

The ideal Worcester 8000 would be the 40kw combi boiler for a home with 4 bedrooms as this gives you that extra power and makes sure that it can cope with higher hot water demands. This combi boiler is also available in a 50kw output too. 

Which is the best combi boiler for a loft?

If you are considering a new combi boiler but want to hide it away in your loft, then the good news is that you can pretty much choose any combi.

All the best combi boilers are compact and lightweight so they should easily be able to fit through a loft hatch and be installed neatly on a wall in the loft space. 

Which is the most energy-efficient combi boiler?

According to the Energy Saving Trust changing to an A-rated boiler could save up to £800 a year on your bills, so if we could all the most energy-efficient combi boiler that would be fantastic, wouldn’t it? well here are the current most efficient combi boilers available right now:

The most efficient combi boiler for a 4 bedroom house is the Viessmann 050-W 30kW.

The most efficient system boiler for a 4 bedroom house is the Viessmann 100-W 26kW system boiler.

Ensuring that you get an energy-efficient combi boiler makes sure that you are not using more gas or energy than is required as older boilers start to become less energy efficient and use up far more gas than a new A-rated unit. 

Read our guide on the most efficient boilers for more info on how to save as much energy as possible with the best energy efficient combi boilers on the market right now with up to 94% efficiency rating. 

Which are the best budget combi boilers under £2,000?

The best budget combi boiler is the Vokera EasiHeat boiler. This combi boiler is perfect for customers who want a well-known brand and a reliable boiler in their homes.

This is a popular boiler for landlords due to the price but we always recommend going for boilers with longer warranties and likely better reliability such as the Ideal Logic C30

The 25kW version of the Vokera EasiHeat is perfect for homes with up to 3 bedrooms, sometimes 4 if there isn’t a high demand for hot water in the property.

Get the best and cheapest deals online right now – Click here.

Which are the worst combi boilers?

As daft as it seems, it is sometimes a good idea to be aware of the worst combi boilers to ensure that you stay away from them and you don’t end up with an unreliable combi that is going to cause you no end of issues.

Luckily in our transparent helpful guide, we have provided you with some of the worst boilers on the market right now.

These boilers have bad reviews, low reliability, and no end of problems and hassles for homeowners and landlords alike. 

Combi boiler vs system boiler – What is the best boiler for your home?

This completely depends on the type and size of the home where the boiler is to be installed.

We would recommend a combi boiler for homes that have 1-2 bathrooms or showers; however, if a home has multiple bathrooms and showers, then a system boiler is a better solution to provide enough hot water. 

System boilers actually store hot water in a cylinder, making it more available when and if you need it.

Combi boilers, on the other hand, heat hot water on demand which means if there are 3-4 showers running at the same time in a home, then your combi will struggle to meet the demand. 

Is a storage combi boiler any good for high hot water demand?

A storage combi boiler is suited to homes with higher hot water demand but no space for a hot water tank, therefore if this sounds like you then yes, they are good. 

Storage combi boilers combine elements of both combi and system boilers, respectively and they allow for instant hot water on demand as well as the ability to store water in a cylinder, making it useful for running multiple water utilities at once. 

Read our full combi boiler vs system boiler guide here to help you make your decision now

Are combi boilers the most efficient type of boiler?

Most modern boilers are highly efficient, with almost all of them achieving an A rating in energy efficiency. However, combi boilers are some of the most efficient boilers available, as they only heat water up when it is in demand rather than storing it in a tank.

This means that the boiler only works hard when hot water is needed, so you’re getting exactly what you pay for with very little waste. 

Is it cheaper to run a combi boiler compared to other boiler types?

Getting a brand new A-rated combi boiler is said to save you around 20-35% on your energy bills each year, making combi boilers one of the cheapest boiler types to run. This is partly due to the fact that they don’t store water like a system or conventional boiler does, so heat isn’t lost when this water is warmed up or cooled down. 

This means all hot water is coming directly from the mains water supply and being heated up, so you get the hot water you need and not excess. The installation fee is also cheaper as no storage tank means fewer parts that need to be fitted by your Gas-Safe registered engineer.

What is the lifespan of a combi boiler?

Modern combi boilers will last around 10-15 years, with some lasting even longer if they are well taken care of and get regular boiler service. Over time, the engineering and technology of your combi boiler will deteriorate, making it less effective as time goes on. 

Once your boiler has gotten to this age and you notice it getting less and less efficient, it is probably a good indicator to look for a new boiler. Getting a boiler replacement will mean a more efficient boiler and, in turn, less money spent on maintenance and less energy wasted. 

What are the cons of a combi boiler?

As we have mentioned, combi boilers are best suited for homes with less water demand, so homes with a lot of taps or more than one shower should probably be fitted with a conventional boiler or a system boiler. 

The water cylinder in these boilers means that it can use the stored water to meet the high demands of hot water, whereas a combi boiler can’t as they don’t come with a water tank. 

Does a combi boiler need to be running all the time?

Whilst you should have your combi boiler running all of the time so you’re able to produce hot water when you want it, your central heating system doesn’t need to be running all the time. 

Turning your central heating off or turning it down can help save money, especially during the Summer months with it being warmer. However, make sure to regularly test your central heating so it is ready for Winter and also make sure to do the same during the Winter so your pipes don’t freeze.

Best combi boiler: Final verdict

If you are unsure what combi boiler size is best for your home then take our 9 step boiler fixed cost quote calculator.

If you’re spending a fair bit of money on a combi boiler, you may want to protect it with one of our boiler cover plans too which also includes a free annual boiler service

We always make sure that everyone understands the importance of getting an annual gas boiler service in order to maintain their boiler and keep their warranty valid.

As part of the warranty terms and conditions, all boilers in our guide must be serviced once a year for 10 years or more.

This must always be completed by a Gas Safe registered heating engineer. Make a service plan with Boiler Central so you don’t forget!

At Boiler Central we will find you the best combi boiler for your home, at the perfect size and performance and even a fixed price that you can purchase online by card or get an instant finance decision.