Plumbing is something many of us take for granted—until something goes wrong. If you start hearing strange noises coming from your water pipes, it could be a sign of trapped air. These sounds can range from constant rattling to prolonged vibrations within your walls.
In addition to unusual pipe noises, your faucets may start behaving unpredictably. They might spray, “spit,” or release water in an uneven stream. In most cases, trapped air in the pipes won’t cause significant damage to your plumbing system. However, persistent banging and splashing noises can eventually lead to problems.
So, how do you remove air from your water pipes?
How Does Air Get into Water Pipes?
Air can enter your plumbing system in various ways. It often happens after installing new pipes or replacing plumbing components. Such work doesn’t even need to occur in your own home—if plumbing work has recently been done in your neighborhood, air bubbles may find their way into your household pipes.
Air can also get trapped after a large-scale water supply shutdown, especially if the system is fully or partially drained. When the water supply is restored, the air isn’t expelled immediately—it is pushed through by water pressure.
When you turn on the faucet, the air escapes faster than water, causing the pipes to release bursts of air mixed with water. Air doesn’t distribute evenly throughout the system and often forms “pockets” in the upper sections of the pipes. These air pockets are what cause the sputtering effect when you turn on the faucet.
Common Causes of Air in a Private Home’s Water System:
- Air can be pulled in through a check valve when water levels drop.
- Leaks at pipe joint connections due to worn seals.
- Air remaining in the system after its first launch.
Why Is It Important to Remove Air from Water Pipes?
In most cases, air in water pipes won’t cause severe damage to your plumbing. After all, it’s just air. However, trapped air can lead to issues such as:
- Excessive pipe vibrations and humming noises.
- Reduced water pressure, leading to weaker flow (especially noticeable when showering).
- Faucets “spitting” or producing unstable water streams.
- Corrosion and rust buildup.
- Water hammer (hydraulic shock).
Trapped air can cause a water hammer, a sudden surge of pressure that gradually weakens pipes, leading to cracks. Over time, a damaged pipe may burst. The main danger of water hammer is that it often goes unnoticed until significant damage occurs.
If you suspect trapped air in your system, avoid turning on the water, gas water heaters, washing machines, or dishwashers. It’s also recommended to shut off the toilet water supply to prevent damage to its fittings.
How to Remove Air from Water Pipes
For Apartment Buildings:
If the water supply in your apartment building has been shut off, the best approach is to close the main valve at the inlet and wait until pressure in the system stabilizes. Once the pressure is high enough, air will mix evenly with water, and the water will flow more consistently. At first, the water may come out with a hissing sound and appear white due to air bubbles.
For Private Homes:
If the air is trapped due to leaks at pipe fittings, repair the affected joints.
To remove air from the system, various devices can be used, such as automatic air vents, mechanical valves (e.g., a “Mayevsky valve”), or shut-off valves (ball valves, taps, etc.).
A simple manual method you can try at home:
- Turn off the water pump.
- Shut off the main water supply. This step is crucial; otherwise, the process will be ineffective.
- Open all the faucets in your home to allow water to flow through every outlet. Keep the pressure low to ensure a controlled drainage of water.
- Once all water has stopped flowing, turn the main water supply back on and let water run through the pipes again. Stop only when a steady, uninterrupted flow is achieved.
- Flush toilets and restart washing machines or dishwashers to ensure complete removal of air pockets.
At this stage, you shouldn’t hear any unusual noises from the pipes. The absence of noise and a consistent water stream indicate that the air has been successfully removed.
If the problem persists, it may be necessary to call a professional. Loud banging sounds followed by silence often indicate a water hammer, which is a more serious issue that requires expert evaluation.