Micro Bore System ~ this system uses 6 to 12 mm diameter soft
copper tubing with an individual flow and return pipe to each heat
emitter or radiator from a 22 mm diameter manifold. The flexible
and unobstrusive pipework makes this system easy to install in
awkward situations but it requires a more powerful pump than that
used in the traditional small bore systems. The heat emitter or
radiator valves can be as used for the one or two pipe small bore
systems alternatively a double entry valve can be used.Hot Water Heating Systems