I have a Bosch Dishwasher that is some seven years old and, when it performs, is very good. It has a cold feed only and is tee'd off the mains supply to the kitchen sink. For the past two years there has been an increasingly frustrating problem with the water supply. The machine starts but won't fill or won't fill mid cycle. I have discovered that this can generally be corrected by turning on the cold tap to the sink and the flow to the machine starts up once more. This used to work with the machine in situ - I now generally have to pull the machine out to get this technique to work. Somebody has suggested that there is a simple valve at the water inlet position to the machine. Is this so and if so, does this simply need to be replaced. I would really like to fix the machine if possible rather than add to landfill!!