Faucets make many noises when turned on. The noises resemble a hammer sound -- a loud banging or pulsing referred to as water hammer. This sound is often frightening, but it has an explanation. Pipes also squeal, squeak or thump. These problems may be the sign of serious problems in your plumbing, but usually it is a symptom of a simple problem.
A bang or bumping sound when your faucet turns on is the result of rattling pipes, which means the pipes shake, or vibrate, when the water comes on due to the pressure in your water lines. The problem is solved by properly securing the pipes to the walls, or wherever they are installed, with pipe braces and brackets. This is a job for professional plumbers and contractors as it takes special tools and knowledge average homeowners might not possess.
Obstructions in the Pipes
Obstructions in the lines might impede water flow and therefore cause the rattling of the pipes against the wall. This sound is similar to the sound made by loose pipes; however, it will be more subdued in most cases if the pipes are properly secured. In homes with newer plumbing, the chances of having a loose pipe are slim. So, if you hear banging or thumping in your pipes when the faucet comes on, you might have something stuck in your pipes. Debris, dirt, hair and other foreign objects, like grass or sediment, clog pipes. Hire a professional plumber to take a look if you feel this is the issue.
Hot Water Squealing
Another common noise in pipes is a squealing sound coming from the hot water pipes. You will know this sound originates in the hot water pipes because it occurs only when the hot water is on. If you turn on just the cold water, the sound does not occur. This sound is basically a result of expanding pipes. When the pipe presses against supports, a squealing is heard. If the sound is really loud, homeowners may opt to change the brackets. Speak to a professional about this repair.
If your faucet makes a very loud sound like a hammer, you have a common problem called water hammer, which is caused by a backup in your water lines that occurs after you shut the faucet off. This hammering noise is just like the banging sound of a loose pipe, but it is a backup of water forcing itself against the faucet valve that causes the issue. Installing an air gap in the faucet drain pipe is the most common method of repair for this issue.