Thank you for making this forum available for non plumbers as well as professionals. As you probably guess, I'm not a professional plumber and need some advice. On the third floor of my duplex, I have what I think is called a Water Hammer. The symptom is that each time I open and close the hot water tap I hear a loud bang. It's only on the hot water tap in the bathroom sink. I tried to drain the water from the system but the banging came back in a few days. After doing some research on the net, I think I need to install a Water Hammer Arrester. I was hopping that someone with experience can help me determine if this is the proper next step and if so where do I put the Water Hammer Arrester. I included a crude map of my setup. I hope its OK.