Best Condensing Boilers for 2022

Best condensing boilers

5 best condensing boiler on the market right now

Choosing the best condensing boiler to buy is a big decision, and it can really feel as if the pressure is on to know precisely which is the right one for you and your home.

In this article we’re aiming to bring you some clarity on what condensing boilers are, what a new boiler cost, and if they’re the right option for you. 

Get online prices on the best condensing boilers in 20 seconds – Click here now

What is a condensing boiler?

A condensing boiler is a boiler that utilises the heat of its gas to warm the water within your homes heating system. With non-condensing boilers, that heat is lost as hot gases disappear into the flue.

While condensing boilers are a type of boiler, it’s important to understand that they can still be either a combi boiler, a system boiler or a conventional boiler.

The impact of the difference between condensing and non-condensing boilers is immense. Condensing systems lose less than 10% of the heat generated, something completely unobtainable for the non-condensing boiler.

Get an online fixed price in 20 seconds:

Q What kind of fuel does your boiler use?

How do condensing boilers work?

Just as with older types of systems, the condensing boiler burns gas to be able to heat the water. This then produces both carbon dioxide and water vapour. The larger heat exchanger in the condensing boiler allows it to recycle the heat within the gases which would otherwise be completely lost through the flue to outside of the home.

Best condensing boilers – By model

Now each manufacturer has a whole range of boilers to choose from, though the combi boiler is the most popular gas boiler installed in the UK.

The combi is the only boiler that heats water on demand, meaning there is no need for water tanks or hot water storage cylinders. So, we’ve selected just one condensing combi boiler from each one to showcase the features that are on offer.

1. Alpha Combi E-TEC Plus

Alpha has gone with stainless-steel heat exchangers for the E-TEC Plus which are designed to be easy to maintain and energy efficient.

Then Alpha has gone with the high-efficiency Grundfos pump and hydroblock assembly, and zinc plated expansion vessel which reduces the effects of corrosion.

The E-TEC comes in 28, 32 and 38kW models with an LPG model available for those homes not connected to a natural gas supply.

2. Baxi 800 Combi

Built-in the UK, this combination boiler comes with an impressive 10-year parts and labour warranty.

It’s small enough to fit into a kitchen cabinet and comes with the Adey Micro2 magnetic system filter to protect and extend the heating system and boiler’s life.

This Baxi condensing boiler comes with a choice of three power outputs, 25, 30 and 36kW.

3. Vaillant ecoTEC plus Combination Store

This innovative boiler is a great choice for larger households. That’s because it combines the convenience of the combi boiler with the hot water storage associated with system or regular heating systems. The water storage is integrated into the back of the boiler, meaning there is no need for a separate hot water tank. The ecoTEC plus delivers 20 litres of hot water per minute and all within 5 seconds.

4. Viessmann Vitodens 100-W

Designed for the smaller well-insulated home, the Viessmann 100-W boiler, efficient and affordable boiler.  Available with the Viessmann tado° thermostat and smartphone app, meaning that you can control your heating system no matter where you are in the world. Available in a range of outputs from 4.7 to 35kW.

5. Worcester Bosch Greenstar 4000

The Worcester Bosch Greenstar 4000 boiler is the most popular boiler in the Worcester Bosch range and they are designed for smaller homes with a single bathroom.

This is a boiler which is very easy to set-up to provide you with your perfect hot water and heating needs. As a low energy boiler, electrical usage is reduced, and when installed with the internet connected Bosch EasyControl the Greenstar 4000 achieves an A+ ErP efficiency rating. Arguably the best combi boiler on the market.

Get an online fixed price in 20 seconds:

Q What kind of fuel does your boiler use?

Cost of condensing boilers

To help you choose, we’ve researched the latest prices for all five of the best combi condensing boilers that we’ve mentioned in this article.

ManufacturerModelGuide Starting Price
AlphaCombi E-TEC Plus£800
Baxi800 Combi£930
VaillantecoTEC plus Combination Store£1,700
ViessmannVitodens 100-W£1,169
Worcester BoschGreenstar i£1,048
Boiler Prices by Brand

Benefits of condensing boilers

Here, we explore three key benefits of a condensing boiler:

1. Energy efficient for a greener home

Non-condensing boilers can operate at less than 60% efficiency. So that means that 40% of your fuel costs are disappearing up the flue. If your boiler is over ten years old, then that probably means that it’s a low efficiency non-condensing type and you should consider a boiler replacement.

2. Cost efficient & help you save money

A high efficiency condensing boiler will save you money due to the energy and heat which is being saved and recycled. The Energy Saving Trust estimates that the average UK household spends more than half of its energy expenditure on providing heating and hot water. With these types of savings, you’ll see a big difference in the monthly bills.

3. Reduction of carbon footprint

As a condensing boiler generates lower carbon emissions levels than you can do your bit for the environment.

Get an online fixed price in 20 seconds:

Q What kind of fuel does your boiler use?

Best condensing boilers – By brand

We’ve identified five key boiler manufacturers who can supply you with the perfect heating system for your home.


Although Alpha has only been in the heating industry for around 50 years, they are part of Immergas, which operates in 30 countries worldwide. Alpha have achieved a very impressive 4.8/5 on Trustpilot for their replacement boilers, a tremendous achievement for this smaller organisation.


Baxi have been UK manufacturers of heating systems since 1866. Employing more than 6,000 people worldwide in over 100 countries, Baxi is Endorsed by Which? Trusted Traders for their customer service, installation and servicing. A fantastic British new boiler company


Vaillant UK is a family-owned company that has operated for over 140 years. Vaillant Group has a presence in over 20 countries and is the second-largest European manufacturer in the heating sector. When you’re looking searching for ideal condensing boilers, reviews can be important, and Vaillant scores an impressive 4.6/5 on Trustpilot.


Johann Viessmann founded the company in 1917 in Germany. Now, it’s a global business with over 12,300 employees worldwide. Viessmann claim to provide the UK’s most reliable boilers and consistently appear in Which? Best Buy lists. In 2019, Viessmann were named as the top Energy & Heat brand for 2019, in their home country of Germany.

Worcester Bosch

Originally trading as Worcester, they became part of the Bosch Group thirty-four years later in 1996. Worcester Bosch has two manufacturing plants in the UK, in Worcester itself and then one in Derbyshire.

Worcester Bosch has been voted as one of the top recommended brands by YouGov, featuring in the top ten best brands for domestic appliances.

Get an online fixed price in 20 seconds:

Q What kind of fuel does your boiler use?

Don’t forget that boiler installation costs need to be added to these prices and that many manufacturers require you to use a Gas Safe registered installer to validate the warranty.


Condensing boilers are not only highly efficient, but they are also cheap boilers to run and better for the environment. We know that getting to grips with the different types of boilers can be challenging, whether that’s going for gas or oil, or understanding the right boiler size for your home. This is why the Boiler Central fixed price quote finds the best boiler deals for your home. Simply answer a few questions about your heating and hot water needs and you’ll see the most suitable boilers suggested for you, it’s that easy!

Get an online fixed price in 20 seconds:

Q What kind of fuel does your boiler use?

Get a great price on a Which? Best Buy boiler online in minutes

Pick your install date | £0 Deposits | 0% Interest-FREE
12-Year Warranty on Worcester Bosch & ViessmannGet a Quote Now >