What causes banging when flowing hot water gets up to temp, then stops while flow rate drops to 30% normal, OR I turn on the cold tap too?
I live in a single story house, and about 4 months ago started getting a banging in the pipes. It ONLY happens when the hot water tap is open in the bathroom and gets up to temperature, and immediately stops when the cold tap is also opened. Furthermore, if I let it continue with only the hot tap open, the water coming out drops to about 30% the normal amount, and stays there, with NO more banging. Turning the tap off and on again restarts the banging, but the resulting reduced flow and stopping of the banging happens more quickly. We made absolutely no changes in the house plumbing system before (or since) this started. I have been unable to determine exactly where the banging is happening, since leaving the tap open and then crawling under the house is long enough to have it stop banging and just having reduced flow.