A manifold is installed in a central location i.e. an airing cupboard. From the manifold a pair of polyethylene plastic pipes are run under the floorboards and connected to each radiator or towel rail. At the point where the pipes protrude from the floor or ceiling, copper or chrome can be attached. Enough slack is left in the plastic pipe for this joint to be accessed. Each room has it's own roomstat connected to a thermal actuator via a wiring centre which is located at the manifold position. (See diagram below)
The heating system is controlled by a basic programmer. When the programmer is "on" the roomstats take control. If one or more rooms require heat the thermal actuator opens the corresponding valve on the manifold and also fires the boiler thus sending heating water only to the rooms that require it. As an additional bonus when the heating system is "off" (night time for example) the system automatically reverts to setback mode at 15°C so the home never goes completely cold.
With the introduction of a more sophisticated programmer, we can further enhance the control of the system. This enables the homeowner to control different rooms at different times using different temperatures. Roomstats are available in two types: hardwired (5 volt) or wireless and both can be used in bathroom situations.