There are some things to consider before you go choosing a new central heating system, but dont worry! At AWS we will help you through the whole process from making your choices based on your specific needs to tailor fitting those solutions to your property.

Take a look at some of the pro's and con's of the three main heating systems we offer 

Conventional boilers

The open vent boiler, sometimes called 'heat only' provides central heating and hot water through a hot water storage cylinder in an airing cupboard and cold water top up tanks in the loft.The feed and expansion tank keeps the heating system topped up as the water evaporates, and also allows the water in the pipes to expand as it is heated. This system is found in many old houses, and can work with a new condensing boiler, however most people upgrading a system like this will opt for a system boiler and remove the tank from the loft.


  • More than one outlet can operate at the same time
  • Domestic hot water has good flow rate


  • Cannot have radiators higher than the water tank
  • Pipes are open to the atmosphere so can be prone to airlocks, and increased risk of corrosion.
  • Water tank components (eg ball valve) may require extra maintenance
  • Extra tank in loft takes up space
  • When the hot water in the storage cylinder runs out, you have to wait until it reheats

Combination boilers

The combination boiler is very popular in flats and houses with one bathroom. They are very efficient and provide central heating and hot water on demand without the need for a separate hot water cylinder, freeing up valuable storage space. They are compact and easy to fit alongside kitchen cabinets if space is limited. They are dependant on good mains pressure water entering your property, pressure may drop if more than one outlet is used at the same time, although this can be minimised by fitting a large enough boiler.


  • Space saving, no need for tanks in the loft, or a hot water cylinder.
  • Cheaper to run as there is no hot water store to heat.
  • Unlimited, instant hot water on demand.


  • Cannot run multiple baths or showers at the same time.
  • Unsuitable if your property has low mains water pressure.
  • Lower flow rate than a system boiler.

Under Floor Heating

Underfloor heating is difficult to retro fit as it takes up a lot of depth, however in an extension such as a conservatory it could be ideal, where there isn't enough space to hang a radiator. Water that is heated from the boiler is pumped through a network of underfloor tubes that cover the entire floor space. Modern underfloor heating operates at lower temperatures than radiators and is therefore cheaper to run. The heat radiates upwards from the floor and is distributed evenly. It is considered by many to be the most pleasant type of heat distribution as there are no hot or cold spots.


Programmers control the time that the heating and hot water switch on. Generally you should set the programmer to come on half an hour before you get up, and switch off half an hour before you go to bed. Most programmers allow several on/off settings a day, so you can set them to switch off if you are out during the day.


Thermostatic radiator valves (TRVs) allow you to have different temperatures in each room, typically a bedroom would be set to 3 and a living room set to 5. The numbers on the dial represent the following temperatures:

1 = 11° C2 = 13.5° C3 = 16° C
4 = 18.5° C5 = 21° C6 = 23.5° C