Condensing Boiler Guide: Prices, Pros & Cons and Leading Brands

Since the April 1st 2005, all gas boilers installed or replaced must be high efficiency condensing models to comply with government regulations. The same legislation for oil-fired boilers was applied in 2007. The move is part of an environmental strategy to force all homes in England and Wales to become more energy efficient.

There are three different types of high-efficiency condensing boilers available today, including combi boilers, system boilers and heat only boilers. The average price of a condensing boiler ranges between £455 and £2,800, depending on the type, brand, model and output. But these boiler prices do not include the installation cost, which can start from £600 and go up to around £1,500.

As you can see, a new condensing boilers is a considerable investment and prices vary rather a lot. You also need to pay for a professional installation on top of the price of the boiler, so you’ll be looking at a final cost of between £1,055 and £4,300.

If you’re looking for a boiler replacement and want to know what a condensing boiler actually is, how it works and the pros and cons of getting one installed, our helpful guide covers it all and makes it easy for you to compare condensing boiler prices.

What is a Condensing Boiler?

A condensing boiler will run on either gas or oil and has all the same elements as a non-condensing boiler. The key difference is that a condensing boiler recovers latent heat that would usually be lost through the flue as exhaust gases. To reuse this latent heat, a condensing boiler sends the exhaust gases to its heat exchanger, which cools and condensates the gases back into a liquid form (known as condensate). This recovered heat is then used to warm up the cool water that enters the boiler.

The name ‘condensing’ comes from the condensation produced by the boiler itself. As a condensing boiler burns much less fuel to supply your home with energy, it is more energy efficient than non-condensing boiler models. If you decide to install an efficient condensing boiler, you should reduce your carbon footprint and save money on your energy bills.

Advantages of Condensing Boilers

Since condensing boilers use less fuel to heat your home and water, their efficiency could save you hundreds of pounds on your annual bill. Some manufacturers say that up to 98% thermal efficiency can be achieved when installing one of their condensing models, whereas non-condensing models can only operate in efficiencies of 70-80%. The main advantages include:

Increased Energy Efficiency: One of the main benefits of condensing boilers is that they are much more energy efficient (at least 25% more) than non-condensing models. They also comply with current legislation.

Environmentally friendly:Condensing boilers can significantly reduce carbon emissions and waste less energy by recycling heat that would otherwise be wasted, and therefore reduce their impact on the environment.

Cost Effective:Unlike non-condensing systems, condensing boilers burn less fuel and recycle the heat back into the boiler to ensure less energy is wasted. As a result, you could save between £130 and £300 on your energy bills.

There are some arguable disadvantages as well, which are that condensing boilers have a shorter lifespan than other boiler types and can easily go wrong and be more expensive to maintain due to their complex systems.

Condensing Boiler Prices

The price you will pay is influenced by many factors, such as boiler size, output and efficiency rating. Many top brands offer highly efficient condensing boilers, which vary in price from around £450 to £3,566.44 depending on the manufacturer and how sophisticated the boiler model.

We’ve put together a range of comparison tables that enable you to compare just some of the combi, system and heat only condensing models available from different boiler brands to give you a better idea of prices. The prices listed include VAT but exclude the cost of installation.

Worcester Bosch Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Greenstar 32 CDi Compact Combi	H - 680 mm W - 390 mm D - 280 mm	32 kw	13.1 l/min		£ 1,232.21
Greenstar 40 CDi Classic Regular	H - 760 mm W - 440 mm D - 360 mm	40 kw	N/A		£ 1,621.88
Greenstar Danesmoor System 25	H - 855 mm W - 370 mm D - 600 mm	25 kw	N/A		£ 2,004.00
Greenstar Highflow 440 CDi Combi	H - 850 mm W - 600 mm D - 600 mm	29 kw	20.1 l/min		£ 2,053.68
Greenstar Utility Regular 50	H - 1012 mm W - 520 mm D - 815 mm	50 kw	N/A		£ 2,142.12
Greenstar Danesmoor System 32	H - 855 mm W - 370 mm D - 600 mm	32 kw	N/A		£ 2,272.73

Ideal Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Independent C30 Combi	H - 700 mm W - 395 mm D - 278 mm	30 kw	12.4 l/min		£ 651.92
Logic Heat 24	H - 700 mm W - 395 mm D - 278 mm	24 kw	N/A		£ 790.50
Logic Max System 24	H - 700 mm W - 395 mm D - 278 mm	24 kw	N/A		£ 859.96
Vogue Combi 32	H - 740 mm W - 445 mm D - 330 mm	32 kw	13.1 l/min		£ 1,085.00
Mexico HE 15	H - 850 mm W - 450 mm D - 530 mm	15 kw	N/A		£ 1,103.70
Vogue Max System 26	H - 740 mm W - 445 mm D - 330 mm	26 kw	N/A		£ 1,131.83

Biasi Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Advance Plus Combi ERP 25	H - 700 mm W - 400 mm D - 290 mm	25 kw	13.3 l/min		£ 597.60
Advance Plus System ERP 25	H - 700 mm W - 400 mm D - 290 mm	25 kw	N/A		£ 607.50
Inovia Combi ERP 25	H - 700 mm W - 400 mm D - 290 mm	25 kw	11.4 l/min		£ 653.70
Advance Plus 7 System ERP 30	H - 700 mm W - 400 mm D - 295 mm	30 kw	N/A		£ 659.00

Vokera Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Compact A 29	H - 715 mm W - 405 mm D - 248 mm	29 kw	11.9 l/min		£ 485.00
Mynute VHE 20 Open Vent	H - 740 mm W - 400 mm D - 338 mm	20 kw	N/A		£ 492.00
Vision System 20	H - 715 mm W - 405 mm D - 248 mm	20 kw	N/A		£ 545.00
Evolve Combi 32	H - 740 mm W - 420 mm D - 350 mm	32 kw	14.2 l/min		£ 785.00
Mynute 35HE System	H - 780 mm W - 400 mm D - 358 mm	35 kw	N/A		£ 922.91
Linea One Combi	H - 780 mm W - 400 mm D - 358 mm	38 kw	15.6 l/min		£ 1,069.99

Keston Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Keston S30 System	H - 700 mm W - 395 mm D - 278 mm	30 kw	N/A		£ 1,094.79
Keston Combi 30	H - 700 mm W - 395 mm D - 278 mm	30 kw	12.4 l/min		£ 1,195.64
Keston Heat 45kW	H - 850 mm W - 500 mm D - 360 mm	45 kw	N/A		£ 2,340.87

Ferroli Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Ferroli i29 Combi	H - 680 mm W - 400 mm D - 330 mm	29 kw	15.6 l/min		£ 479.00
Modena 18 HE System	H - 600 mm W - 400 mm D - 320 mm	18 kw	N/A		£ 575.00
Modena 27 HE Combi	H - 600 mm W - 400 mm D - 320 mm	27 kw	11.1 l/min		£ 610.26
Energy Top W80	H - 945 mm W - 445 mm D - 400 mm	80 kw	N/A		£ 2,783.00

Viessmann Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Vitodens 050-W 29 Combi	H - 707 mm W - 400 mm D - 350 mm	29 kw	12.1 l/min		£ 809.45
Vitodens 100-W 26 Heat	H - 600 mm W - 375 mm D - 285 mm	26 kw	N/A		£ 961.58
Vitodens 100-W 30 System	H - 700 mm W - 400 mm D - 350 mm	30 kw	N/A		£ 1,167.33
Vitodens 200-W 26 Combi	H - 850 mm W - 450 mm D - 360 mm	26 kw	14 l/min		£ 1,516.24
Vitodens 200-W 30 System	H - 850 mm W - 450 mm D - 360 mm	30 kw	N/A		£ 1,519.34

Vaillant Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
ecoTEC Pro Combi 28	H - 720 mm W - 440 mm D - 338 mm	28 kw	11.1 l/min		£ 925.00
ecoTEC Plus Regular 24	H - 600 mm W - 375 mm D - 320 mm	24 kw	N/A		£ 958.46
ecoFIT Pure System 25	H - 720 mm W - 390 mm D - 259 mm	25 kw	N/A		£ 1,115.90
ecoTEC Exclusive Combi 35	H - 720 mm W - 440 mm D - 474 mm	35 kw	14.5 l/min		£ 1,425.60

Baxi Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Duo-tec Combi 28	H - 780 mm W - 450 mm D - 345 mm	28 kw	11.5 l/min		£ 819.20
EcoBlue Heat 21	H - 625 mm W - 370 mm D - 270 mm	21 kw	N/A		£ 900.57
Megaflo System 24	H - 780 mm W - 450 mm D - 345 mm	24 kw	N/A		£ 909.62
EcoBlue Advance Combi 24	H - 763 mm W - 450 mm D - 345 mm	24 kw	9.8 l/min		£ 914.81
EcoBlue Advance Heat 30	H - 625 mm W - 370 mm D - 270 mm	30 kw	N/A		£ 981.09
EcoBlue System 32	H - 700 mm W - 390 mm D - 295 mm	32 kw	N/A		£ 1,127.99

Potterton Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Gold Combi 28	H - 780 mm W - 450 mm D - 345 mm	28 kw	11.5 l/min		£ 696.28
Titanium Combi 24	H - 625 mm W - 370 mm D - 370 mm	24 kw	N/A		£ 817.44
Promax System 18	H - 750 mm W - 450 mm D - 345 mm	18 kw	N/A		£ 848.52
Promax Ultra Combi 24	H - 763 mm W - 450 mm D - 355 mm	24 kw	9.8 l/min		£ 963.11
Assure Heat 30	H - 700 mm W - 390 mm D - 270 mm	30 kw	N/A		£ 1,002.03
Ultra System 28	H - 626 mm W - 370 mm D - 270 mm	28 kw	N/A		£ 1,250.00

Glow-Worm Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Easicom3 System 25	H - 740 mm W - 418 mm D - 300 mm	25 kw	N/A		£ 622.74
Essential Combi 28	H - 740 mm W - 418 mm D - 300 mm	28 kw	11.7 l/min		£ 658.00
Energy Regular 25	H - 600 mm W - 375 mm D - 280 mm	25 kw	N/A		£ 788.40
Ultimate3 System 25	H - 740 mm W - 418 mm D - 300 mm	25 kw	N/A		£ 820.00
Flexicom Combi 35	H - 700 mm W - 390 mm D - 280 mm	35 kw	14.4 l/min		£ 880.00
Easicom3 Regular 25	H - 600 mm W - 375 mm D - 280 mm	25 kw	N/A		£ 887.92

Alpha Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Evoke Combi 28	H - 712 mm W - 440 mm D - 255 mm	28 kw	12.1 l/min		£ 625.00
E Tec Combi 33	H - 712 mm W - 440 mm D - 255 mm	20 kw	N/A		£ 834.48
E Tec Plus Combi 28	H - 712 mm W - 440 mm D - 268 mm	33 kw	14.1 l/min		£ 929.33
Intec GS Combi 40	H - 843 mm W - 442 mm D - 457 mm	50 kw	N/A		£ 2,233.14

Ariston Condensing Boiler Prices

MODEL	DIMENSIONS	OUTPUT	MAX FLOW RAT	EFFICIENCY	TYPICAL PRICE
Clas HE 24 Evo Combi	H - 595 mm W - 400 mm D - 295 mm	24 kw	10.3 l/min		£ 659.00
Clas HE 24 Regular	H - 595 mm W - 400 mm D - 295 mm	24 kw	N/A		£ 659.00
E-System One 30	H - 745 mm W - 400 mm D - 331 mm	30 kw	N/A		£ 1,140.00
Clas System One 30	H - 745 mm W - 400 mm D - 401 mm	30 kw	N/A		£ 1,140.00
Clas Net One 38 Combi	H - 745 mm W - 400 mm D - 385 mm	38 kw	15.5 l/min		£ 1,140.00

Please note: Your decision should not be based on pricing alone. Prior to choosing a condensing boiler, you must ask a Gas Safe engineer to assess your home and typical heating and hot water usage habits to ensure you pick a boiler that will satisfy the needs of your household.

Boiler Energy Efficiency Ratings Explained

The government and boiler manufacturers introduced SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) in 1999, which was a simple system that awarded each boiler model a rating from A to G for energy efficiency.

In 2015, SEDBUK was replaced by the ErP (Energy related Products) directive, a scheme that aims to achieve the EU’s 20-20-20 targets. These targets are as follows:

• A 20% reduction in the EU greenhouse gas emissions (from 1990 levels)
• A 20% improvement in overall energy efficiency across the EU
• A 20% increase in energy produced from renewable sources

The ErP directive is designed to make boiler brands improve the efficiency and performance of their products, as well as ensure end-users are aware of how efficient their boilers can be. Its purpose is to also help European governments lower carbon emissions and help consumers to reduce their energy bills. Today, all boilers have an efficiency rating from A+++ to G, which must be clearly displayed on each appliance – so make sure you look out for this label when purchasing a new boiler.