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Water Hammer Problems

A water hammer refers to the surge of pressure or a wave that occurs when a moving fluid is suddenly stopped or forced to change its direction suddenly. In a pipeline system, this is a common phenomenon that occurs when a valve is suddenly closed and a pressure wave builds in the pipe. Water hammer can cause several problems from noise to vibration and sometimes even a pipe collapse.

Listed below are a few questions answered by Experts on issues related to water hammers.

When I turn off my kitchen faucet, I have a water hammer problem. What can I do to fix it?

To fix this, you might need to install shock absorbers which are known as water hammer arrestors in the water lines that connect to the sink. A less expensive way of tackling this would be to ensure that the piping is securely hung. This may not stop the hammer but it can lower the noise.

My bathroom sink has a water hammer. How can I get this fixed with a plumber?

There are two basic reasons why you could have a water hammer.

1. When plumbing pipes are installed in homes, bushings are also put in to isolate the pipes from the wall studs. If the pipes undergo repairs and, in the process, the isolators fall off or move, the pipes will have enough room to move around in the hole. In this situation, if the water pressure is high and the water is turned on and off quickly, the stopping motion will make the pipe start hitting the studs.

2. The same problem can occur if the water pressure is too high in general.

There are a few ways to handle this problem:
1. Lower the water pressure to the right PSI
2. Locate the pipes that are loose and fix them
3. Put in anti-hammer devices that act as shock absorbers. They will prevent the moving water from stopping suddenly.

My hot water is stopping because of a water hammer. It starts again after I bang the pipe. How can I set this right?

Case details: This problem is affecting all the faucets in the house. Water hammer arrestors have been installed on the washing machine inlet valves.

In most cases, water hammers shouldn’t cause the pressure to drop. It’s possible that the reason you are facing this problem is because a washer has become loose. Find the valve on the line before any branches and change it. It should fix the problem.

I have a water hammer problem that occurs every time I turn on a faucet or the toilet. The noise is getting louder. How can I fix it?

In most cases, a water hammer happens because of a valve that closes fast. From what you say, it’s possible that one of the reasons for this to occur is a fault with your water meter. If this isn’t the case, it could be that there is a loose washer in the main valve. Water hammer can also happen if you have a malfunctioning backflow preventer.

To begin with, see if you can locate the sound by standing at the water entrance with the water turned on. Also get in touch with your water utility company to check the meter. If you receive well water, examine the check valve at the pressure tank. In the absence of a check valve, examine the foot valve within the well located at the beginning of the suction line and check if it is faulty. Once you locate the exact problem, you can go about fixing it.

Water hammer arrestors are often used to stop water hammers from causing any damage. These devices, also known as air cushions, air chambers or water capacitors, are placed close to the quick-close valve, and are designed with a piston that has a cushion of air behind it. Once you close the valve, the piston helps to re-direct the pressure into this separate chamber. This, in turn, pushes the piston into the cushion of air and the pressure gets released. The absence of pressure protects the pipe and any appliances from damage. The piston is also designed with a water seal. This prevents the air on one side of it from dissolving into the water of the pipe and does not allow the water in the pipe to flow into the air compartment situated above the piston. If you are facing problems with water hammer and need further information on how to stop it, consult an Expert to help you tackle the problem.
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