Central heating DIY

There are several types of central heating system, but once you understand the differences you should be able to figure out what type you have - that will make it much easier to work on should the need arise.

There are three different types of boiler:

• Conventional (non condensing)
   
• Combination (usually referred to as "combi")
   
• System
   

Your central heating system will depend on which type of boiler you have:

• Conventional
  
  Until the 1980s, all systems installed were of the conventional type. These systems require a hot water storage cylinder, and two cold water storage cisterns in the roof space - one is for feeding the hot water cylinder, the other for feeding the central heating system. If the roof space is uninsulated, the tanks can suffer from frost related problems.
  
  
• Combination
  
  Combi boilers are now the most popular choice. They heat water instantly, and thus have no storage tanks in the loft space. Combi's will usually have the pump and even the time clock and temperature control included with them.
  
  
• System
  
  A system boiler is a combi boiler with the Domestic hot water system removed and is used for central heating only.