Best Boilers Under 20kW

That’s why we’ve put together this helpful guide for the best boilers under 20kW to help you decide which small boiler is best for your home.

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Ideal Logic+ System - 15kW/18kW

Perfect for smaller homes, the Ideal Logic+ System is the smallest in physical size of our range, meaning it can be easily stored away in a kitchen cupboard or smaller space. Thanks to its incredible 90% energy efficiency, this system boiler can seriously lower your heating bills, making it a worthwhile investment.

With so many fantastic features packaged into a compact system, it’s no wonder the Ideal Logic+ was voted the 2013 Good Housekeeping Reader Recommended Best Combi Boiler and became the Winner of the Queen’s Award for Enterprise in Innovation for 2013.

Boiler Specs

• Warranty: 10 Years on parts and labour

• Boiler type: System

• Efficiency: A-Rated @ 90%

• Low Output Options: 15kW and 18kW

• Dimensions W 395mm, D 279mm, H 700mm

Ideal Logic+ Regular - 15kW/18kW

Just like the Ideal Logic+ System version, the Logic+ Regular (or Heat Only) boiler is incredibly compact, making it ideal for fitting into smaller spaces, freeing up storage space in the rest of your home. As with all of the Logic+ range, the regular boasts a high energy efficiency rating of 89%, meaning you’ll never have to worry about rising energy bills due to inefficiencies.

As part of the Logic+ range, this boiler was also supported by the Queen’s Award for Enterprise 2013 and received the Good Housekeeping Reader Recommended Status in 2013 and 2017.

Boiler Specs

• Warranty: 10 Years on parts and labour

• Boiler type: Heat Only

• Efficiency: A-Rated @ 89%

• Low Output Options: 15kW and 18kW

• Dimensions: W 395mm, D 279mm, H 700mm

Worcester Bosch Ri 18kW/21kW

The Worcester Bosch Greenstar Ri boiler is a compact, wall mounted boiler that is ideal for smaller and medium sized homes. Small enough to be installed in a standard kitchen cupboard, the boiler can be used in combination with our range of high efficiency Greenstore cylinders for a complete Worcester system solution for your home.

Boiler Specs

• Warranty: 10 Years on parts and labour

• Boiler type: Heat Only

• Efficiency: A-Rated @ 92%

• Low Output Options: 18kW and 21kW

• Dimensions: W 390mm, D 270mm, H 600mm

Worcester Bosch Greenstar 4000 18kW/21kW

According to Worcester, the Greenstar 4000 has been built on all the tried, tested and much-loved features of the Greenstar i, making it instantly familiar and yet totally transformed with a whole new modern design.

If a stylish, high-tech boiler is what you’re looking for, then this is the one for you with a full colour text display, innovative ‘Quick Tap’ water saving functions and wireless connectivity with Bosch EasyControl.

Boiler Specs

• Warranty: 10 Years on parts and labour

• Boiler type: System

• Efficiency: A-Rated @ 91%

• Low Output Options: 18kW and 21kW

• Flow rate: 10.2 l/m

• Dimensions: W 400mm, D 310mm, H 724mm

Viessmann Vitodens 100-W 16kW/19kW

Efficient, quiet and affordable, the Vitodens 100-W gas condensing boiler is our most popular solution available at iHeat, delivering impressive results from a compact frame. Featuring innovative technology and services combined with reliability and longevity and comes ready for smart technology, helping you to optimise your heating and save on energy costs. What more could you ask for?

Boiler Specs

• Warranty: 10 Years on parts and labour

• Boiler type: Heat Only

• Efficiency: A-Rated @ 89.5%

• Low Output Options: 16kW and 19kW

• Dimension: W 400mm, D 350mm, H 700mm

Looking for a Boiler Under 20kW?

At iHeat, you can get a brand new boiler plus installation at an affordable price. All you have to do is answer a few questions about your existing boiler and home and we can give you a free, fixed quote in a matter of seconds.

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