Our Guide to the Best Boilers 2021

Updated July 2021

What is the best boiler? This is a question we are asked frequently. For the past few years, the answer has been Viessmann boilers for gas boilers, and Navien for oil boilers.

In this guide, we will detail exactly why Viessmann and Navien boilers are the best boilers available in the UK in 2021, whilst also highlighting other notable boiler manufacturers, plus the best ranges for specific applications, the best boilers by fuel type, and the best boilers by budget.

In this guide:

Need a new boiler?

After extensive testing and based on our engineers’ 30+ years of experience, we believe Viessmann to be the best gas boiler brand and Navien to be the best oil boiler brand available in 2021. Read on to find out how we came to this conclusion.

Combi boilers are generally suited to smaller properties, whilst conventional and system boilers are better equipped to fulfil the heating and hot water demands of larger homes.

In terms of boiler size, we recommend the following:

One/two-bedroom flat or house: A combi boiler up to 29kW

Three-bedroom semi-detached/terraced house: A combi boiler ranging from 28kW to 35kW, a conventional boiler from 18kW to 24kW, or a 25kW storage boiler

Four-bedroom detached house: A conventional boiler or a system boiler ranging from 30kW to 38kW

For more detailed recommendations on the best boiler for your home,  jump to the section – What is the best size boiler for my property?

The best gas boiler brand

The best gas boiler brand

Viessmann

Established in 1917, Viessmann is a fourth-generation family-owned German boiler manufacturer. It has operated in the UK since 1989 from its head office in Telford, Shropshire. 

In addition to the UK, they also operate in 30 other countries around the world and offer gas condensing boilers, heat pumps, combined heat and power units, oil boilers, domestic hot water cylinders, steam boilers and commercial hot water boilers.

Why do we consider Viessmann to be the best gas boiler brand?

Stainless steel heat exchangers are utilised across the entire Viessmann range

Viessmann is one of the few boiler manufacturers that utilises stainless steel heat exchangers across its entire range. 

Not only are Viessmann’s heat exchangers made from stainless steel, but they are also made of Inox-Radial stainless steel, which is the highest grade of stainless steel beneath surgical steel. 

For the uninitiated, stainless steel offers many benefits when used for heat exchangers and is far superior to the aluminium heat exchangers utilised by competitors. The biggest benefit of a stainless steel heat exchanger is the chromium content which makes it highly resistant to corrosion in a wide range of pH levels, this ensures retained efficiency for the lifetime of the appliance. Aluminium heat exchangers on the other hand are prone to corrosion and this will ultimately affect the efficiency of the boiler. 

Viessmann utilise high-quality quality components

All of the components utilised within Viessmann boilers are high quality. Whereas a competitor may utilise plastic or composite materials, Viessmann will utilise brass components instead. The benefit of this is components that will not perish and cause the boiler to break down.

Viessmann invests heavily in innovation

Investment in innovation is key to Viessmann’s success and this is reflected in the use of future-proof technology across its boiler range. Examples of this are shown in the Vitodens 100-W and the Vitodens 111-W, both of which have both been updated for 2021. 

The Vitodens 100-W comes H2 ready, meaning that it has been developed to be able to use a 20:80 hydrogen mix as its fuel source. This means that the boiler is able to utilise the fuel source that has been proposed by the UK government as a replacement for natural gas in order to meet its carbon-neutral goals.

Both the Vitodens 100-W and the Vitodens 111-W also come with integrated WiFi, this enables the boilers to connect to the internet, be controlled remotely, and increases their efficiency with smart technology that learns your heating schedule and automatically adjusts to suit this. 

Both of these boilers also feature the ability to be remotely monitored by a heating engineer, meaning issues can be diagnosed immediately without the need to visit the property.

Viessmann boilers are highly efficient

Viessmann is renowned for the efficiency of its boilers, with its entire boiler range offering efficiencies in excess of 94%. 

Viessmann manufacture all of the components within its boilers

Unlike its competitors, Viessmann manufactures all of the components for its UK boiler range at its global headquarters in Allendorf, Germany. Viessmann boilers are also developed, assembled, tested and shipped from the same production facility.

Viessmann parts are now widely available in the UK

Going back a few years, one of the biggest criticisms of the Viessmann boiler range was the limited availability of parts in the UK. However, Viessmann recognised this themselves and remedied the problem by partnering with Plumbase. Now spare parts for Viessmann boilers are stocked at every Plumbase branch in the UK.

It’s a multi-award-winning manufacturer

Viessmann is the frequent recipient of accolades including the Red Dot Award and HVR Awards. Notably, the Vitodens range has been awarded the coveted Which? Best Buy Award every year since 2017.

Viessmann offer some of the longest warranty periods of any boiler manufacturer

The entire Viessmann boiler range is available with comprehensive parts and labour warranties of up to 12 years.

Brand Model Output (kW) Price (Installed) Fuel
Viessmann Vitodens 050-W Combi Boiler 29 From £2100.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 050-W Combi Boiler 35 From £2200.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W Combi Boiler 26 From £2500.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W Combi Boiler 30 From £2600.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W Combi Boiler 32 From £2700.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W System Boiler 11 From £2400.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W System Boiler 19 From £2500.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W System Boiler 25 From £2600.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W System Boiler 32 From £2700.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 111-W Storage Combi Boiler 25 From £3300 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 111-W Storage Combi Boiler 32 From £3500 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W Combi Boiler 30 From £3300 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W Combi Boiler 35 From £3400 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W System Boiler 19 From £2700 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W System Boiler 26 From £2800 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W System Boiler 30 From £2900 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W System Boiler 35 From £3000 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Interested in a Viessmann boiler?

The best oil boiler brandThe best oil boiler brand

Navien

Established in 1978 in South Korea, Navien has been operating in the UK since 2014 and has been offering combi boilers here since 2017. Whilst a new entrant to the UK boiler market, Navien is the world’s best-selling boiler brand and its factory in Seotan in South Korea, is the largest boiler manufacturing facility in the world.

Already the market leader in its native South Korea, the manufacturer of the best-selling boiler in the USA, and a market leader in Russia, Navien is already shaking up things in this country with its cutting-edge oil boiler technology.

Why do we consider Navien to be the best oil boiler brand?

Navien uses stainless steel heat exchangers across all of its boilers

Like Viessmann, Navien is also an advocate of the stainless steel heat exchanger and utilises this across its entire oil boiler range. Navien stainless steel heat exchangers have been designed to prevent corrosion and erosion, ensuring an extended lifespan for the boiler and its efficiency. 

All Navien boilers utilise blue flame technology

One of the standout features of the Navien oil boiler range is its use of blue flame technology across all boiler models, something that few competitors offer. Blue flame technology is designed to provide superior efficiency and guarantees low NOx emissions.

Navien boilers are made with high-quality components 

The stainless steel and brass components utilised within the Navien range go a long way to stop the boiler from falling foul of the corrosion that plagues boilers that utilise plastic and copper parts.

Navien boilers are filled with innovative technology

Navien joins a long list of South Korean companies including Samsung, LG, and Hyundai, who are bringing technological innovations to the rest of the world. In addition to Navien’s blue flame technology, Navien oil boilers are also equipped with the ability to set heating zones so that the heat in different areas of a property can be controlled independently. In addition to this, the boilers are compatible with Navien’s Smart Plus smart thermostat app, which allows heating and hot water to be controlled remotely wherever you are in the world. Further to this, the Smart Plus app also enables the boiler to connect to the internet, monitor the weather via the OpenWeatherMap, and adjust the inside temperature based on the weather conditions outside.

Navien offers a highly efficient boiler range 

Navien offers highly efficient oil boilers, with its LCB700 oil boiler offering 93% efficiency, for example.

Navien boilers are easy to install and repair

Navien has invested heavily in the development of its boiler range so that the boilers are not just user-friendly but also easy to install, service and repair. The benefit of this to the consumer is cheaper labour costs as the engineer won’t have to spend as much time on-site with the boiler.

When it comes to parts, they are now widely available

We held back on recommending Navien until we were satisfied that spare parts for its boilers were readily available. We can confirm that they now are widely available across the UK and are carried in both Plumbase and Screwfix branches across the UK.

Navien’s warranty periods give you peace of mind

All Navien boilers come with a 10-year parts and labour warranty. Both long and comprehensive, this warranty period provides you with peace of mind when purchasing a Navien boiler.

Brand Model Output (kW) Price (Installed) Fuel
Navien LCB700 Blue Flame Oil Combi Boiler 21 From £3800.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Navien LCB700 Blue Flame Oil Combi Boiler 28 From £3900.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Navien LCB700 Blue Flame Oil Combi Boiler 36 From £4000.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Interested in a Navien boiler?

The boiler brand with the best reputation

The boiler brand with the best reputation

Worcester Bosch 

Originally founded in 1962 in the UK, Worcester became part of the Bosch Group in 1996. Today, they are the UK’s market leader in domestic boilers and offer a comprehensive range of gas, oil and LPG boilers.

Based in Worcester, all Worcester Bosch gas and LPG boilers are assembled at this site, whilst its oil boilers are assembled at an additional site in Clay Cross, Derbyshire.

Why do we consider Worcester Bosch to be one of the best boiler brands?

It’s the boiler brand with the best reputation in the UK

Worcester Bosch has earned its right to be named one of the best boiler manufacturers. It is a household name and this is due to the reputation that it has achieved since the 1960s. You only have to take a look at the Worcester Bosch Trustpilot profile to get a glimpse into the public’s perception of this boiler brand – here you will find that the company currently has 19,543 excellent reviews out of a total of 24,739.

It’s the UK’s market leader in domestic boilers 

As you would expect with such a great reputation, Worcester Bosch is also the UK’s market leader in domestic boilers. The reason for this also comes down to the fact that they are the preferred choice of boiler to install by British Gas. Many people will have a Worcester Bosch boiler in their home, will have developed a sense of brand loyalty as a result and will choose Worcester Bosch for their next boiler.

When it comes to parts, there’s always excellent availability

Being a UK based company, Worcester Bosch parts are incredibly easy to come by and can be purchased in every branch of Wolseley and Plumbase across the UK.

Worcester Bosch boilers are filled with innovative engineering 

Whilst originally a British company, since 1996, Worcester has been backed by the engineering might of Robert Bosch GmbH. Being owned by Bosch has seen Worcester Bosch boilers utilise innovative engineering that enables them to achieve efficiencies in excess of 90%.

Worcester Bosch offer cutting edge technology

A great example of this is the Bosch EasyControl, Bosch’s smart thermostat. This gives you a stylish, sleek wall-mounted controller that would make a great addition to any modern home. Featuring looks like no other thermostat, this is equipped with lights that will update you on the changes your heating system is making, and will also show you practical information such as the time and the weather outside.

Utilising smart radiator thermostats with Bosch EasyControl allows you to add individual room control to your property so that the heating can be set room by room. 

Bosch EasyControl also allows for smart integrations, meaning that you can operate your home using voice commands with Amazon Alexa, Google Home, Google Assistant, and Siri Shortcuts, and allows for control remotely using Facebook Messenger.

Whilst accompanying Bosch EasyControl iOS and Android app allows up to 10 mobile devices to be able to control a Worcester Bosch boiler remotely and be provided with useful information about the current status of the heating system. 

Worcester Bosch is a multi-award-winning brand

The quality of Worcester Bosch’s product range has been recognised by being awarded a Which? Best Buy award for 11 years for its Greenstar gas boiler range. Whilst they have one of the most esteemed awards in the UK, in the form of a Royal Warrant for supplying boilers to Her Majesty The Queen’s Sandringham Estate. In addition to this, Worcester Bosch has also received awards from OFTEC, the Best Factory Awards, and the Build it Awards.

Brand Model Output (kW) Price (Installed) Fuel
Worcester Bosch Greenstar 8000 Combi Boiler 30 From £2900.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 35 From £3000.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 40 From £3100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 45 From £3200.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 50 From £3300.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i Combi Boiler 25 From £2300.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i Combi Boiler 30 From £2400.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 9 From £1700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 12 From £1800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 15 From £1900.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 18 From £2000.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 21 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar i System Boiler 24 From £2200.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Si Compact Combi Boiler 25 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Si Compact Combi Boiler 30 From £2200.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Heatslave II Combi Boiler 18 From £3600.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Heatslave II Combi Boiler 25 From £3800.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Heatslave II Combi Boiler 32 From £4000.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 2000 Combi Boiler 25 From £1720 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 2000 Combi Boiler 30 From £1920 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 Combi Boiler 25 From £2100 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 Combi Boiler 30 From £2200 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 System Boiler 12 From £2091 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 System Boiler 15 From £2191 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 System Boiler 18 From £2291 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 System Boiler 21 From £2391 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 System Boiler 24 From £2491 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 30 From £2900 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 35 From £3000 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 40 From £3100 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 45 From £3200 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 8000 Combi Boiler 50 From £3300 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch GB162 System Boiler 50 From £3500 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch GB162 System Boiler 65 From £3700 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch GB162 System Boiler 85 From £4900 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Worcester Bosch GB162 System Boiler 100 From £5500 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Interested in a Worcester Bosch boiler?

The best UK manufactured boiler brand

The best UK manufactured boiler brand

Vaillant

Established in 1874, Vaillant is a completely family-owned German manufacturer of boilers based in Remscheid, North Rhine-Westphalia.

One of the leaders in the European heating industry, Vaillant is a pioneer in boiler technology and not only patented the “closed-system” gas-fired bathroom boiler in 1894 but also developed the first central heating boiler in 1924 and pioneered the combi boiler over 35 years ago. 

Vaillant offers a range of gas boilers to the UK market, all of which are manufactured in the UK at its Derbyshire plant.

Why do we consider Vaillant to be one of the best boiler brands?

Vaillant boilers are renowned for quiet operation

Vaillant has received the Quiet Mark accreditation for its incredibly silent design and soundproofing technology. The Quiet Mark is an international award given to manufacturers of the quietest products. Vaillant’s boilers are deserving of this, given that its boilers operate as quiet as 43dB, which is around the same operating volume as an A-rated fridge.

Vaillant are noted for offering highly efficient boiler ranges

Vaillant products are noted for their high energy efficiency ratings and low emissions, with efficiencies of up to 94% offered on the ecoFIT pure, ecoTEC exclusive with Green iQ, and ecoTEC Pro Combi boiler ranges. 

Vaillant invest heavily in making technologically advanced products

In addition to energy efficiency, Vaillant is also best known for its technological innovation. This is reflected in its smart thermostat, vSMART, and the accompanying iOS and Android app. Compatible with every boiler in the current Vaillant range, vSMART adds smart control to Vaillant heating systems and allows you to control your boiler anytime and anywhere you have an internet connection. This level of control enables you to reduce your energy bills by controlling exactly when your home is heated and enables you to utilise voice commands via Amazon Alexa to control your heating. 

vSMART will also learn about your home’s heating needs and will make your boiler work smarter to minimise your energy bills, and will monitor local weather conditions and adjust your heating accordingly. 

Vaillant offer a number of boiler ranges with premium quality components

A number of Vaillant boilers are equipped with premium quality brass components and importantly a stainless steel heat exchanger that is designed to be resistant to corrosion and ensure the boiler’s efficiency for the lifetime of the appliance. 

The following Vaillant boiler ranges are equipped with stainless steel heat exchangers – Vaillant ecoTEC exclusive with Green iQ combi, Vaillant ecoTEC plus combi, Vaillant ecoTEC plus combination store, Vaillant ecoTEC pro combi, Vaillant ecoTEC exclusive with Green iQ system, and Vaillant ecoTEC plus system.

Vaillant are a multi-award-winning manufacturer 

Vaillant’s quality has been recognised by being awarded Which? Best Buy awards, the Quiet Mark approval and the Superbrands title.

Brand Model Output (kW) Price (Installed) Fuel
Vaillant ecoFIT pure Combi Boiler 25 From £2250.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Combi Boiler 30 From £2300.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Combi Boiler 35 From £2400.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure System Boiler 12 From £2000.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure System Boiler 15 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure System Boiler 18 From £2250.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure System Boiler 25 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure System Boiler 30 From £2800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Conventional Boiler 12 From £2000.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Conventional Boiler 15 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Conventional Boiler 18 From £2200.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Conventional Boiler 25 From £2300.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoFIT pure Conventional Boiler 30 From £2400.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC exclusive with Green iQ Combi Boiler 35 From £2800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC exclusive with Green iQ Combi Boiler 43 From £2900.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC exclusive with Green iQ System Boiler 27 From £2500.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant  ecoTEC plus Combi Boiler 25 From £2500.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant  ecoTEC plus Combi Boiler 32 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant  ecoTEC plus Combi Boiler 35 From £2700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant  ecoTEC plus Combi Boiler 38 From £2800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 12 From £2150.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 15 From £2250.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 18 From £2350.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 24 From £2450.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 30 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant Vaillant ecoTEC plus System Boiler 37 From £2700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC plus Combination Store 38 From £2900.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC Pro Combi 24 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC Pro Combi 32 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC Pro Combi 35 From £2700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC Pro Combi 38 From £2800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Interested in a Vaillant boiler?

The best affordable boiler brand

The best affordable boiler brand

Ariston

Ariston was founded in Marche, Italy in 1930 and has been manufacturing boilers since 1960. 

Today, Ariston is number 4 in the world for boilers and number 1 in the world for hot water. Seen as a mid-range boiler brand, they are well-established throughout Europe and are an emerging brand in the UK. 

Predominantly known for space-saving boilers, Ariston offers options for both commercial and domestic applications. 

Why do we consider Ariston to be the best affordable boiler brand?

Ariston is a great boiler brand for customers on a budget 

Ariston boilers are by no means a premium boiler range but that doesn’t mean they offer throwaway products. Coming in at the lower end of the price range for boilers, Ariston boilers are still reliable products and offer great value for money. We would definitely recommend them to landlords looking for a new boiler in their rental properties and to first time buyers with smaller homes.

The entire Ariston range is equipped with stainless steel heat exchangers

Despite coming in at a cheaper price point, the entire Ariston boiler range is still equipped with stainless steel heat exchangers. Normally a component reserved for premium boiler manufacturers like Viessmann and Vaillant, by utilising its own patented Xtratech™ stainless steel heat exchanger, Ariston ensures its boilers are not susceptible to corrosion and will retain their efficiency for longer.

Ariston boilers are compatible with smart technologies

Even though they are a cheaper boiler brand, Ariston boilers still feature the ability to integrate with smart technologies. Utilising Ariston Net with an Ariston boiler, allows for remote management of the boiler utilising the accompanying iOS and Android app, and also enables you to utilise voice commands via Google Home, Google Assistant, Amazon Alexa, and Siri Shortcuts.

In addition to the remote control of your boiler, Ariston Net also increases the efficiency of an Ariston boiler by giving you detailed information about your energy consumption and how to better manage this. 

Whilst in the event of system failure, Ariston Net will send you a notification in real time that informs you of the error code and required action. 

Brand Model Output (kW) Price (Installed) Fuel
Ariston Alteas ONE Net Gas Combi Boiler 30 From £2400.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Alteas ONE Net Gas Combi Boiler 35 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas ONE Gas Combi Boiler 24 From £1700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas ONE Gas Combi Boiler 30 From £1885.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas ONE Gas Combi Boiler 38 From £2000.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas System ONE Gas System Boiler 18 From £1600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas System ONE Gas System Boiler 24 From £1700.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Clas System ONE Gas System Boiler 30 From £1800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston E-Combi ONE Combi Boiler 24 From £1750.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston E-Combi ONE Combi Boiler 30 From £1800.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston E-System ONE Gas System Boiler 24 From £1940.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston E-System ONE Gas System Boiler 30 From £2050.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Genus ONE Net Gas Combi Boiler 24 From £2500.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Genus ONE Net Gas Combi Boiler 30 From £2100.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Ariston Genus ONE Net Gas Combi Boiler 35 From £2600.00 (inc. VAT) Gas Find out more about this boiler Get a quote for this boiler
Interested in an Ariston boiler?

What is the best type of boiler for my property?

There is no one size fits all when it comes to a boiler. The best boiler for you is dependent on your property type, your heating and hot water needs, and the space you have available. There are three main types of boiler systems to choose from:

Combi Boilers

which boiler is best 2019, combi boiler

A combi boiler will be the best type of boiler for your property if one or more of the following apply to you:

  • You won’t ever require hot water from more than two taps or showers at a time 
  • Your property only has one to two bathrooms 
  • Your property is small to medium in size
  • Your property doesn’t already have a hot water cylinder
  • Your property doesn’t already have a cold water storage tank 
  • Your property has a hot water cylinder but your hot water demands don’t warrant this and you’re looking to achieve additional space in your property
  • You have a redundant boiler system such as a back boiler
  • You already have a combi boiler installed in your property

Combi boilers are now the most common type of boiler installed into UK properties. This is due to advances in technology meaning they can handle higher heating and hot water demands than ever before. However, combi boilers aren’t for every property and household. 

A combi boiler may not be suitable if any of the following apply to you:

  • Your property has an older heating system with old radiators, buried pipes, and long/complicated pipe runs 
  • You have low incoming water pressure. A combi boiler requires a flow rate of at least 10 litres per minute, if you don’t have this then this type of boiler may not be suitable

If you are not familiar with combi boilers, we’ve created the following easy-to-understand guides which may help:

Interested in a combi boiler?

Conventional Boilers

which boiler is best 2019, conventional boilers

A conventional boiler will be the best type of boiler for your property if one or more of the following apply to you:

  • You will require hot water from more than two taps or showers at a time 
  • Your property has two or more bathrooms 
  • Your property is larger in size
  • Your property already has a cold water tank in the loft 
  • Your property already has a hot water cylinder in the airing cupboard
  • You have an older heating system with older radiators, buried pipes 
  • You already have a conventional boiler installed in your property
Interested in a conventional boiler?

System Boilers

which boiler is best, system boilers

A system boiler will be the best type of boiler for your property if one or more of the following apply to you:

  • You will require hot water from more than two taps or showers at a time 
  • Your property has two or more bathrooms 
  • You plan to add a new bathroom to your property in the future
  • Your property is larger in size
  • Your property already has a hot water cylinder in the airing cupboard
  • Your property doesn’t have a cold water tank in the loft 
  • You already have a system boiler installed in your property
Interested in a system boiler?

What is the best boiler fuel type for my property?

In addition to system type, boilers are also categorised by fuel type. The type of fuel you can use in your property can be much more restrictive and ultimately depends on whether your property is connected to the mains gas grid or not.

Below we have listed the best boiler fuel types that are suitable for your property depending on whether you are connected to the mains gas grid.

Connected to the mains gas grid 

The best option:

Gas Boilers

Natural gas

In the UK, natural gas is the most common fuel used for heating our homes. There are a number of reasons for this. Firstly, because there is a wide choice of gas boilers to purchase in the UK. Secondly, gas boilers offer the best value for money – both in purchasing the boiler and having it installed and in terms of your energy bills going forward. Ideal for homes with multiple bathrooms

If your home is connected to the gas mains grid, at present we would still recommend purchasing a natural gas boiler. However, we would recommend purchasing a gas boiler that has the capability to adapt to other fuel sources. Across the Viessmann, Worcester Bosch, Vaillant, and Ariston ranges, there are gas boilers that can also be used with LPG. Whilst the new Viessmann Vitodens 100-W has been designed with the UK’s future energy targets in mind and is equipped to be powered using a blend of 80% natural gas and 20% hydrogen.

Not connected to the mains gas grid

The best options:

Gas BoilersOil 

For the four million households in the UK not connected to the mains gas grid, oil has always been the preferred choice due to it working in a similar way to gas to provide heat and hot water. 

To have an oil boiler installed in your property you will also need to have an oil tank too, so you will need to ensure that you have the room to accommodate this. 

Oil boilers are generally more expensive to purchase and install than gas and LPG boilers but they are cheaper to run than LPG boilers, with oil costing 4.8p per kWh, on average*.

LPG

LPG boilers are quickly becoming a go-to alternative to oil boilers. The reason for this is that they are often much cheaper to purchase and install because most of the mains gas boilers on the market can be converted to accommodate LPG using an inexpensive LPG conversion kit.

Like oil boilers, LPG boilers will need the space to accommodate a fuel storage tank.

LPG boilers are, however, more expensive to run than oil boilers, with LPG costing 7.2p per kWh.

Electric

Electric

We would only recommend an electric boiler for a flat or a smaller house that doesn’t have space for a tank to store the fuel outside. The reason for this is because there aren’t many electric boilers available that can meet the higher demands for heat and hot water that large properties and households require.

It should be noted that electric boilers are more expensive to purchase than oil and LPG boilers but they are cheaper to install. As they have no emissions, electric boilers do look set to become more commonplace in order to meet future energy targets.

Currently, electric boilers are much more expensive to run than oil and LPG boilers, with the electricity costing 16.4p per kWh, on average.

*Figures taken from Energy Saving Trust
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What is the best boiler for my property?

There is no one size fits all with boilers. The best boiler for you will depend on a number of factors, these are namely the size of your property and your hot water demands.

As established above, combi boilers are generally suited to smaller properties, whilst conventional and system boilers are better for larger homes.

The most important consideration in your purchasing decision is choosing the right size boiler for your property. The size of the boiler will depend on the size of your house and the number of bathrooms, as this will determine your heating and hot water requirements.

With modern condensing boilers even if you buy a larger capacity boiler, they will modulate energy usage between 5kW and 30kW depending on the load.

Flat

What is the best boiler for a one/two-bedroom flat or house?

A one/two bedroom flat or house will usually only have one bathroom. For this reason, you won’t need a high capacity boiler. We recommend nothing more powerful than 29kW.

Even if you currently have a system or conventional boiler in your property, we would recommend converting this to a combi boiler. Doing this will save you space and allow you to save energy as a combi boiler will only heat the water you need. 

Our recommendations for a one/two-bedroom flat or house:

Brand Model Output (kW) Price (Installed) Fuel
Viessmann Vitodens 100-W Combi 26 From £2500.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 25i Combi 25 From £2300.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC pro Combi 24 From £2100.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Navien LCB700 Blue Flame Oil Combi Boiler 28 From £3900.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 050-W 29 From £2100.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler

Semi-detached house

What is the best boiler for a three-bedroom semi-detached or terraced house?

If you have a three-bedroom semi-detached or terraced house, you will usually have one main bathroom, a downstairs toilet, and possibly an en suite bathroom. As all of these locations will require hot water, we would recommend a higher capacity combi boiler ranging from 28kW to 35kW. 

If a combi boiler is not an option, we would instead recommend a conventional boiler ranging from 18kW to 24kW. 

A third option would be a storage combi boiler such as the Viessmann 111-W Storage Combi Boiler which is equipped with an in-built hot water storage tank in order to be able to provide the hot water which a property of this size requires. 

Our boiler recommendations for a three-bedroom semi-detached or terraced house:

Brand Model Output (kW) Price (Installed) Fuel
Viessmann Vitodens 111-W Storage Combi Boiler 25 From £3300 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W Combi Boiler 32 From £2700.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar 4000 Combi Boiler 30 From £2200 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Ariston Clas ONE 30 From £1885.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 200-W Combi Boiler 30 From £3300 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 050-W Combi Boiler 35 From £2200.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Navien LCB700 Blue Flame Oil Combi Boiler 28 From £3900.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler

Detached house

What is the best boiler for a four-bedroom detached house? 

A four-bedroom house will usually have two or more bathrooms, for a property of this size we recommend a conventional boiler or a system boiler ranging from 30kW to 38kW

We wouldn’t recommend a standard combi boiler because this type of boiler wouldn’t be able to cope with multiple showers, taps and appliances being used at the same time. However, there are storage combi boilers that would be suitable.

Our boiler recommendations for a four-bedroom house:

Brand Model Output (kW) Price Fuel
Viessmann Vitodens 111-W Storage Combi Boiler 32 From £3500 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Viessmann Vitodens 100-W System Boiler 32 From £2700.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Worcester Bosch Greenstar Si Compact Combi Boiler 30 From £2200.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Vaillant ecoTEC plus System Boiler 37 From £2700.00 (inc. VAT) Gas/LPG Find out more about this boiler Get a quote for this boiler
Navien LCB700 Blue Flame Oil Combi Boiler 36 From £4000.00 (inc. VAT) Oil Find out more about this boiler Get a quote for this boiler
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