As another in our series of helpful tutorials, the Balkan Drain Team will explain what a plumbing air chamber is and how it is used to prevent water hammer. You may think this is a device you would never have to use or install, but think again. Whether you live in a small town or a big city, a plumbing air chamber is present in many homes and buildings and helpful in them all.
Water Hammer and the Need for a Plumbing Air Chamber
It is only so common for plumbing pipes, especially metal ones, to produce a banging noise occasionally. This is especially true when water is shut off or opened abruptly. The same noise may also happen when you cut off water intake to appliances such as a dishwasher or a washing machine. This can be an effect of water hammer aka water hammer noise.
Water hammer is caused when water is sent rushing quickly, as soon as you open a faucet or a valve. It flows in the direction you desire for its use. Then all of a sudden, a halt of the flow happens when the valve is closed abruptly. This creates a shock wave inside your water pipes – known as water hammer.
A shock wave pushes some pipes to wiggle around, vibrate, and want to pull apart. It can also cause a vibration that makes your pipes bump into each other or the framing of your building. The loud noise that you hear is technically called hydraulic shock; these are water hammer sounds.
Water does not readily compress. Therefore when it smacks into an elbow or bends inside an empty pipe, it makes a loud banging sound. Water hammer can blow your pipes apart. That is when an air chamber installed in your piping system can save you from damage. An air chamber provides a point where water can expand or contract, and to not put pressure on your water piping system.
The potential damage of water hammer
Left untreated, the frequent effects of water hammer are that water pipes break apart and can cause flooding and damage. It can also loosen pipe joints in multiple sections of the plumbing. Plastic pipes are subject to damage as well, but you don’t hear noise as loud as those produced by metal materials. While plastic pipes may not crack due to the shock wave, they can flex, bend, or blow apart.
A plumbing air chamber is used to eliminate water hammer
Properly installed plumbing incorporates a form of cushion to soften the blow of hydraulic shock. This is called a plumbing air chamber and is vital in preventing water hammer. This chamber only has one thing to do: it provides a space for the shock wave without producing the noise. This chamber is filled with air, as the name implies. The air in the chamber gets compressed or expands as it absorbs the shock wave of sudden movement of water inside your pipes and this a great way to go about fixing water hammer.
Unlike water, air is much more easily compressed and, hence acts like a shock absorber. You can think of it as the more traditional version of a pressure regulator relying solely on physics rather than on mechanical parts.
A plumbing air chamber is not a sophisticated device. The cushion is often a plumber-fabricated device. It is made of a simple pipe attached to water supply lines between the shut-off valve and a faucet, spigot, or any plumbing outlet. Ready-made plumbing air chambers are also available. It is nothing more than a stub of pipe capped on one end, attached to a supply line on the other, and containing air. Most air chambers are installed vertically on horizontal supply lines.
If the supply line is in vertical position already, an additional run of short horizontal pipe can be added. Since this dead-end pipe is installed in a way that partly intersects water flow, the pipe also contains a pocket of air.
A plumbing air chamber in practice
In practice, the air in the chamber compresses temporarily under water pressure as you shut off a valve or faucet. Pressure is absorbed to minimize or even eliminate the banging noise. One of the most common sources of banging and noisy pipes is the supply line to a washing machine, but an air chamber can be installed throughout the building, too. Building codes in some areas may require a plumbing air chamber in specific locations. An air chamber (water hammer arrestor) can be relatively easily installed by an experienced local plumber.
Maintaining a plumbing air chamber
The biggest problem with traditional air chambers is how easy they are to become water-clogged, rendering them useless. Regular draining of the supply line can remedy the issue nonetheless. The ideal method to air–fill the chamber is to close the individual water appliance’s shut-off valve instead of turning off the water from the main valve. To get rid of water in a plumbing air chamber and refill it with a pocket of air, follow these instructions:
- Shut off the main valve and open the uppermost plumbing fixtures in your home.
- Open the lowest faucets in your house. As the water is drained out, the chambers are once again filled with air. Close this faucet once the water stops flowing.
- Open the main valve slowly, and leave the uppermost faucet open. Water will rise throughout the system, but the chambers should remain full of air.
To prevent frequent clogging, air chambers must be larger in diameter than the supply line to which it is connected. One thing to notice is that this additional plumbing component may not be practical in tight spaces. If that is the case, have a professional plumber install the alternatives. Some alternatives are mechanical arrestors, or pressure regulators instead. Always pay attention to your local building code because even the installation of minor additional components may require a permit. If in doubt, call a professional.
A little bit about Team Balkan
Team Balkan is NYC’s largest house sewer, water service line, and drain cleaning family of companies. Established in 1952, we have a history of service and expert advice that spans over 70 years and is built on a reputation of integrity and trust. A recipient of multiple Angie’s List Super Service Awards, the company is now providing its services in Nassau County and Westchester as well.
Today the Balkan remains one of the most experienced and longest-running plumbing companies in New York City. Whether you need expert information about an item such as a plumbing air chamber, or prompt and professional sewer, drain, and water main service, contact Balkan. We are available 7 days a week, and after-hours as well.
