Some of my pipes have had to be replaced because they totally furred up. But after fitting one of your units (In 15 minutes) the damaging effect of Hard Water has come to an end. I fitted the unit and thought that maybe, if I was lucky, after a month or two I would notice a small difference. Imagine my amazement today, less than two weeks after fitting the device, when I looked inside my kettle, which for years has been coated in calcium, to find it CLEAN and CLEAR of all but a couple of chunks still clinging to a small part of the spout. I rinsed it vigorously and the very last chunks washed away so that the kettle is now spotless inside. If my kettle is spotless so are my water pipes!