Something that has been bothering me, and Google is no help in finding a solution:
I live in a larger two story urban home with three bathrooms on a municipal water supply, and periodically I will be startled by a sudden LOUD rushing of water through the drainage pipes. No fixtures are in use when this happens, and as far as I can tell the draining water is limited to what is already standing in the supply pipes.
When the trickling/draining is done, my pipes are left with lots of air remaining inside; if I turn on the water at any faucet, it will spit and sputter for a few seconds, and flushing the toilet results in an unpleasant BANG as the air exits the supply line as the tank refills. I will hear my water heater make noise as if it is suddenly heating a bunch of water at once. (This heater is brand new; could this be the issue?)
I can’t find leaks coming from any fixtures, nor am I finding any unusual areas of moisture.
Help? Any ideas as to what could be causing this, or how to make it stop?
I read and reread your post with great interest, and I can’t make sense out of your problem. How do you know the sound is coming from your drainpipes? The only way water can enter the DWV system is by going into a fixture drain… Do you have leaking faucets or a leaking water closet tank? Sputterring faucets indicate air in your water supply pipes.