Have you ever turned off one of your faucets only to experience a loud noise accompanied by vibrations? If so, you experienced “water hammering” and had yourself a case of noisy water pipes. Water hammering is caused when a fast-moving stream of water travels down a narrow pipe and suddenly comes to a closed valve where it must come to an unexpected halt. It can be fixed.
Regardless of what your water source is, the truth is that constant water can not compress itself. For this reason, if the water must come to an abrupt stop it will result in a loud thud that can be heard throughout the entire house. This is why the problem is referred to as “water hammering.” Unfortunately the problem doesn’t end at the loud noise that gets created; the hammering is also capable of damaging joints and connections in the pipe.
Some people often wonder why a loud noise isn’t created every time a fixture is turned off. Really the answer is quite simple. First of all, water valves do not generally close quickly and unexpectedly. Most valves are designed to close slowly simply to prevent water hammering. However, overtime the gaskets in a faucet get old and brittle and eventually cause the faucet to close more quickly. This commonly results in a water hammer.
Water hammering is expected to happen once your valves start to close quickly, so to prevent this problem from arising, air chambers are built into the plumbing system. Air chambers act as cushions to prevent water from slamming against the piping. Unlike water, air compresses which makes it capable of absorbing the shock of the fast-moving water before it has a chance to slam against the end of the pipe.
Most household plumbing systems include air chambers. They are typically built into the plumbing system at critical locations such as the clothes washer or dishwasher. These areas are hot spots for watering hammering because it’s where electric shut-off valves close rapidly. However, some homes have air chambers built at every location where water is turned on and off. It’s often hard to spot air chambers because they are tucked away within the wall with the rest of the pipes.
The air chamber acts as if it were an upside-down water glass. Once filled with air it becomes a perfect cushion for the streaming water to collide with. However, in older systems there is the chance that air can leak from the air chamber. If it fills with water than it becomes useless and will make the water supply system noisy and prone to damage.
To resolve a water hammer problem, your best bet is to replenish all air chambers with air. The process of doing this is very simple. The first thing you should do is shut off your home’s main water supply valve. Once the water is off you will need to drain all remaining water from your pipes. Do this by opening a few faucets inside your house. Next, find the faucet at the lowest elevation; it is usually located outside. Turn this faucet on to drain all water from the pipes.
The reason you want to clear your pipes of water is because you want to add air. As the water is drained from the pipes, it is replaced by air. With all the water drained, you should then reopen the main valve. You will notice air being pushed out of the water lines causing a sputter as it exits the faucets inside. However, air will remain in the upside-down air chambers. Test out your faucets by running water and see if your water hammering problem has been cured.
Two Things To Keep In Mind
Sometimes noisy water pipes can occur when there is a loose pipe-mounting strap. This can happen even if all the air chambers are in good condition. Before refilling your air chambers, be sure to check all accessible pipes to ensure that they are properly and tightly connected.
There is another kind of air chamber called a shock absorber. It is said that shock absorbers won’t leak and will last forever, but they are designed in a much more complicated fashion and many feel that the fewer mechanical devices you have in your plumbing system, the better off you are.