Pipe Rattling From Waterhammer
A pressure gauge reacting to the waterhammer emanating from the toilet tank when the fill valve shut off. The gauge is connected to an outdoor hose bibb located 16 feet downstream of the cold water takeoff to the toilet. The red needle shows the highest pressure recorded by the gauge. After the waterhammer, it's pegged against the zero post of the 200 psi gauge.
Sound Volume in My Sister's Bedroom
As an experiment, I conjured up a simple waterhammer arrestor by attaching a capped hose to the sink faucet next to the toilet and opened the faucet to connect the hose into the plumbing system. In the video above, you'll note–no water hammer when the toilet fill valve closes. The waterhammer pulse is negatively reflected from the hose. The capped hose also worked by connecting it to the outside hose bibb downstream of the toilet take-off and opening the faucet there to pressurize the air-filled hose.
As another experiment, to show I could recreate the waterhammer with any fast acting valve in the vicinity of the toilet, in the video above I connected a spring-loaded hose spray nozzle to the faucet next to the toilet and let it close quickly after water flow was initiated. I ruined the faucet valve seats with these hammers and had to replace the entire fixture for my parents after this experiment before I left town the next day.
About Me: Most importantly–I'm not a plumbing engineer. I investigate waterhammer accidents in steam systems as is evident from the rest of this web site. I researched the problem discussed on this page for a speech to demonstrate the principles of waterhammer to the Atlanta ASHRAE Chapter, and afterward, as a hobby. Where i say above "I suspect" or "I believe", I've tried to give my reasoning so a knowlegeable reader can see where I'm coming from.
*Preventing Legionallosis, William F. McCoy, PhD, June 2006 ASHRAE Journal.