A high-efficiency water heater and a central heating boiler in a single compact unit.

A gas combination boiler, more commonly referred to as a combi boiler, combines a high-efficiency water heater and a central heating boiler in a single compact unit.

Our combi boiler range is designed for maximum energy efficiency. This means that by choosing a Viessmann combi boiler you will be saving on your energy bills, saving natural resources and protecting the environment.

Our entire combi boiler range is rated Energy efficiency class: A.

All of the boilers in our range are built around our long established reputation for high quality heating systems and are equipped with the latest heating technology. 

Benefits of a Viessmann combi boiler

Combi boilers are becoming an increasingly popular choice amongst our customers across the UK due to their space-saving functionality.

  • Their compact size make them ideal for smaller properties
  • Only one unit is needed to deliver heat to your radiators and hot water to your taps
  • No requirement for a separate pump, hot water cylinder or cold water storage tank
  • They are quicker to install because they have less external components than other boiler systems
  • Hot water is delivered to your taps and shower at mains pressure
  • No risk of cold water storage pipework freezing in the loft
  • They have the ability to adapt to heating demand without constantly switching on/off, meaning smoother operation, less wear and tear on components and greater reliability
  • Comprehensive warranty on the entire range, as standard  

Which gas boiler is the best for you?

Not sure which gas boiler you need? Try our simple tool.

Our most popular combi boilers

Vitodens 050-W gas condensing boiler
Vitodens 050-W

A compact, low-cost gas condensing boiler

With compact dimensions, low weight and quiet operation, the attractively priced Vitodens 050-W gas condensing boiler will integrate effortlessly into any living space. Which? Best Buy, Vitodens 050-W 29 kW Combi.

Discover the Vitodens 050-W
  • Up to 7 years


  • Easy control with

    LCD Display

  • Smart Home

     with tado°

  • Boiler Plus


Discover the Vitodens 050-W
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