Potterton Pipe Assembly (Page 13)
The water pipework can be split in to 2 categories. The first would be the pipes that enable water to be fed in to the heating unit. This would include the mains water supply and the water pipework on the wall jig. The second category would be the pipework inside the appliance that carries water between the different devices of the unit that require it, such as the heat exchanger and the diverter valve.