Have you ever heard a loud bang or thump in the pipe when your toilet tank is filled and it shuts off? What about when your washing machine fills up and starts its cycle? Sometimes this loud bang occurs when you simply turn off a faucet. This loud noise is called “water hammer,” and is appropriately named because it sounds like someone is banging on the pipes in your walls with a hammer.
What Is Water Hammer?
Water hammer is the noise that water makes when it’s forced to stop or change direction suddenly. Water flowing through your pipes is moving, and has momentum. When it is forced to suddenly stop or change direction, it releases a shockwave of energy that has nowhere else to go. So instead of continuing to flow elsewhere, the energy is released as noise. Sounds fairly benign, right? Well, the real problem is the energy release also does other damage to your pipes, fittings, and valves because there is nowhere else for it to go.
There are two main contributors to water hammer: high water pressure and a lack of options for energy built up in your pipes to be released. Valves that close suddenly, like those in your dishwasher, toilet and washing machine, are prone to water hammer damage because they stop flow in a short space of time. This creates the pressure wave, which then functions like a “hammer” hitting the insides of your pipe, the connections, and the valves. Over time, this continual pressure buildup and release leads to leaks, burst pipes and failed valve seals.
Eliminating Water Hammer
So how can you combat this problem which could do devastating damage to your plumbing system? If you’re experiencing water hammer throughout your home, including in nearly every sink, toilet, and appliance, that’s usually an indication of excessively high pressure from your municipal water supply lines. When this is the case, installing a pressure-reducing valve (PRV) at the main supply to your house would immediately solve this problem. However, you might have problems getting the flow to your farthest fixtures with this reduced pressure, depending on the way your plumbing system is set up. Normally one PRV can take care of the whole house, but if you’re having water pressure issues at some of your farther-away fixtures, you may have to install multiple PRVs at locations closer to the problem fixtures.
What if the pressure in your home isn’t the source of that loud banging noise? Well, then you might have an issue with your piping itself. When water has to stop flowing into your appliance or sink, it needs space to dissipate energy. To allow this, plumbing systems usually have a vertical pipe filled with air that buffers the water when a valve closes, known as an air chamber. If this pipe fills with water, the buffer disappears. To resolve this issue, drain your plumbing system completely by shutting off your main water line and then turning on your faucets until water stops flowing. Then clean the waterlogged air chamber to allow air to flow back into it. Then turn your water back on and the banging noise should disappear.
Finally, if neither of these options works you could choose to install a water hammer arrestor. This is a device with an enclosed air chamber designed to buffer your water’s sudden stop when you turn off a faucet or valve. These devices go on the piping to the specific fixture experiencing water hammer, and they are cleverly designed so that they don’t become waterlogged, meaning you won’t have to worry about draining your plumbing to repair them.
Is your home experiencing water hammer? Do you need help figuring out the cause and determining the best way to fix it? Call Lange Plumbing and Fire Protection today at (702) 500-0936 to schedule a service before it destroys your plumbing system!