Bryan Conway
: Every time we shut off running water from any of our faucets, a load banging sound eminates from the pipes, sometimes as many as 10-20 bangs. What is actually happening to have it make such a sound? On several occasions I have shut off the water main and drained the air chambers. That helps a little, but then within days its back to the usual banging. Could it be that the chambers have not drained completely, or is there such a thing as a leak in the chamber that allows it to refill with water? I realize you dont know the layout of our house, but is there any way to fix that without tearing up walls? Should I look in the crawl space below the house for any clues?Bryan, Not all homes were built with air chambers at the highest point.( I like to put them on the shower, second floor) If there are no air chambers in your home, an expansion tank can be added near the water heater. Sizes start at 2.2 gallon. These help allow expansion associated with the water heater. Draining the system down like you have done is good. For pipes to be banging 10 or 20 times it sounds like unstraped pipes. If the sound is coming from the crawlspace, by all means check that out. Walls can be filled with foam without tearing apart the walls. A small hole can be made to insert the foam through. Regards, Terry Love
