How to Stop Water Pipes From Hammering

Do you hear an annoying noise from your water pipes when you shut the faucet off? This might be water hammer. Although it might just seem to be more of an annoyance, it can lead to damage to your water pipe and in some cases, pipe seam bursts. When this happens, it can result to a flooded basement or kitchen, worse, damage to your fixtures and appliances. Here, we will discuss about how you can stop this quite easily. But first, it helps to know what exactly water hammer is and what causes this bothersome sound.

Water Hammer Explained

Water hammer is a thumping or banging sound that occurs when the valve is suddenly closed. It can also be a result of loose pipe or pipe joints as well as worn out valve washer. When water flow is abruptly stopped and the water pipe is loose, the sound may also be accompanied with shaking and rattling of the pipes. If this problem is not resolved, it can loosen pipe brackets and may lead to leaks, if not pipe bursts.

This occurrence does not only happen on bathroom and kitchen pipes but also on washing machines and dishwashers. If the sound is heard after a valve is shut off or the washer changes cycles, it can be hammering water pipes. Conversely, if this happens as the valve is opened it can either be the presence of air in the pipes or water hammer but it is not often the latter unless the valves are more than 3” in size.

How to Solve a Water Hammer Problem

Before you can address this problem, it helps to know where it comes from. First, you have to check the length of the pipe. The longer it is and the bigger its size, the more possibility there is to cause water hammer. Second, observe the time it takes to close the valve. The quicker the valve is shut off, the more the chances that it can lead to creating noise is higher. Third, check on water velocity or how fast it flows. If the water flow is faster than usual, say, from high water pressure, water hammer is more likely to happen.

One of the ways to fix a water hammer problem is to use water arresters (arrestors). This is a piece of device that can be connected to your plumbing system to act as a cushion and absorb the shock caused by water hammer. A mechanical device that needs maintenance, this is a sealed piece that has an air bladder and a spring to cushion the force of flowing water.

Types of Water Hammer Arrester

Single Chamber
This device has copper material and can withstand high water temperatures of up to 180 degrees Farenheit. It has an air chamber which has the ability to absorb the force that comes from water with high pressure. It is also sealed, which keeps it free from moisture and prevents water to seep in. Although it is preferably used on smaller pipe systems around half an inch, it can also be used for ¾ and 1-inch pipes. What’s great about this type is its easy installation feature since it can be attached from any angle to the main pipe. Moreover, if there is no way to attach the single chamber arrester, it can still be converted by soldering it on the pipe with a T-joint.

Mini End Stop
Generally used on washing machines, this type is designed with a fitting, angled at 90 degrees and a thread at the end for easy connection to the washing machine hose. It can be used on varying sizes of pipes and can be set in place through soldering or screwing. As for occupying space, it can be placed behind an interior wall and not take up much space. It also has a watertight chamber that makes it effective in stopping water pipe hammer.

Hose Bib Style
This type is called such because of the internal diaphragm found in the 6-inch wide PVC housing which works to scatter the shock that is a result of closing the water valve quickly. Used on washing machines, this water hammer arrester is connected to the water intake of the washing machine. Of all the three types, this Hose Bib Style water hammer arrester can withstand high water pressure and volume. The only setback of this type is its size. Since it has a large diameter, it cannot be installed inside a wall, unless you are ready to break your walls.

Use Permanent Air Chambers

This is a vertical section of pipe made of copper with a covering at the end. It is attached to a T-fitting and connected to the supply line just before the valve or the appliance, either dishwasher or washing machine. Installation is done on both hot and cold water lines. It also acts as a shock absorber just like the water hammer arrester and compresses the flowing water within the chamber. Permanent air chambers, however, are not as efficient as water hammer arresters when it comes to absorbing shocks after a period of time. When this happens, you can opt to have it refilled with air but you might have to turn off the plumbing system in the house as the pipes need to be drained with water.

Only use permanent chambers if there is an existing one, that is, you might just need to refill the chamber with air. If you have to start from scratch, a water hammer arrester is the better choice. However, you can also combine both.

On Water Hammer on Washing Machines and Dishwashers

Sometimes, you can address the problem without using a water hammer arrester. If the banging is heard when the valve is closed, this means that not enough water is flowing and supplied by the water pipe. This solution might just be a temporary one but it can still work. Try to close the valve partially and see if the noise is gone. If it still occurs, try rotating the valve to a close a little more.

Water hammer problems can be solved as long as the source is identified and water hammer arresters and permanent air chambers are installed. And although this might need the help of a reliable plumbing specialist, it will always help to know a bit of what needs to be done.

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