Boiler Types

Combination (Combi) Boilers

Combi Boilers are the most common boiler application.  Approximately 70% of all boiler applications use a type of combi boiler.  A few different types of combi boiler exist however all types take cold water from the mains water and heat it directly.   This allows a continuous flow of hotwater on demand.  Operating pressures tend to be not as high when compared to other boiler types.

Combi boilers are a simple compact application because you do not require a storage tank in an airing cupboard.  Furthermore combi boiler applications do not require a cold water gravity feed tank located in the loft.  Considerable spare savings can be achieved by selecting a combi boiler central heating system.

Since combi boilers heat water on demand they supply hot water instantaneous for immediate use.  Therefore combi boilers are considered more efficient that other boiler types.  You will also not loose heat through a storage tank as combi setups do not have storage tanks.

However, combi boilers are not perfect choice when considering a boiler type.  Combi boilers a notorious for cutting off hot water to a shower when someone else opens a hot water tap further in the home.

Advantages of Combi Boilers

  • Size Matters.  Combi boilers are very small and can fit into small cupboards.  They also do not require a storage tank or cold water gravity feed tank.
  • Low Cost.  More efficient and cheaper to run
  • Hot Water on Demand.  Instantaneously heats water when demand is realised.  Uninterrupted supply of hot water.
  • Capacity.  Newer combi boilers can provide up to 16 litres of water a minute at 37°C
  • Options.  Modern units can be supplied with a small storage tank as an optional extra.

Disadvantages of Combi Boilers

  • Hot Cold Affect.  Hot water flow can be interrupted when other hot water taps are used.
  • Low Pressure.  Lower water pressure than some other types of boiler.  Therefore less aesthetically pleasing  power showers will be required.
  • Suitability.  Due to low volume, large homes with multiple showers will have to share the lower flow rates.