Best Combi Boiler 2020 – We reveal the Best in Class
How to use this Guide
|Rank||Boiler||Cupboard fit||Boiler cost||Manufacturer Cover||Maximum output||Minimum output||Litres per minute hot water|
|1||Intergas Xclusive 24||Y||£969||10||19kW||3.6kW||10.1|
|2||Vaillant EcoTec Plus||Y||£1,145||10||21kW||3.8kW||10.5|
|3||Ideal Vogue C26||N||£1,005||10||19kW||4.0kW||10.6|
Five steps to find the best combi boiler for you
1) Low minimum output
All boilers operate in a range of outputs, for example, 2-20kW or 6-18kW. The lower the minimum output, the more efficiently the boiler can operate all year round. There are some great high efficiency boilers, often at great prices, from lesser-known brands such as Ravenheat and Intergas. Lower fuel bills are always a priorty, as is warranty length and sometimes brand familiarity. We have put forward boilers with the lowest minimum outputs on the market so you can pick according to your other priorities.
2) Size your hot water requirements
Hot water performance is expressed in litres per minute (LPM) – this is how fast the boiler can heat cold water. The smaller boilers will always be around 10 litres per minute, the bigger boilers over 16 litres per minute. Litres per minute is important if you and your family have multiple bathrooms and shower at the same time in the mornings. The problem with combi boilers that give bigger hot water outputs is that they are too often oversized for the heating system - which is very inefficient. Don't worry, we have only featured boilers that can give a low minimum output alongside great hot water performance.
3) Do you need a cupboard fit?
If you are installing your new combi boiler in a kitchen cupboard you will need a compact boiler. However this are only available in the smaller models.
4) Is the warranty length important?
If you are moving in a few years perhaps you do not need one of the more expensive boilers with a 10 year warranty; a budget end boiler with 5 a year warranty will do and save you £500.
5) What is your budget?
There are some great value boilers even at the lower end. Work within your budget to find a boiler with the longest warranty.
Maximise fuel savings with a compatible heating control
The efficiency of modern condensing boilers comes partly from their ability to operate at low outputs during warmer weathers, hence why a low minimum output is so important. When your home requires just 1-2kW of heat, as it often does, a boiler than can only go down a low 7kW is going to be oversized for much of the year. A boiler than can go down to 2kW will have the efficiency advantage.
However, in order for the boiler to reduce down to 2kW say it must be paired with a compatible control, known as a compensation control. These must speak the same language as the boiler. To find a compatible control for your high efficiency boiler see our Guide to advanced heating controls.