Water hammer is a hydraulic shock that typically occurs in old pipes after a valve is shut off suddenly. A series of loud bangs also occurs when there is an increase in water pressure in your water line.
So, if you live in an old house, you may think that it’s strange why there are banging noises inside your walls after you stop showering or using a washer. But it is not. It is normal for old pipes to get worn out at some point. And in this case, they absorb shock less from changes in the water pressure as you (or other appliances) rapidly open and shut off water supply flowing through the pipes.
For example, washers automatically control water flow from fully on to off within seconds. So, this sudden stoppage causes a hydraulic shock that makes your pipes bang against other fixtures. Over time this can lead to disastrous burst pipes and water leaks!
The video below explains in more detail the science behind the water hammer effect.
So know you know how water hammer works, it’s time for some water hammer solutions before it’s too late!
Check for loose mounting straps in your pipes
If you have been hearing water hammer for quite some time, it can damage the pipes enough to loosen from their straps or supports. It is recommended to do the following steps to know for sure:
- Go to where your pipelines are installed (e.g. basement)
- Find the valve that gives water supply to your toilet or other fixtures
- Observe as you turn on and off the valve; and
- Look for any atypical movements in the pipes
- Secure the loosen pipes with a clamp and see if they still produce a hammering sound afterward
If the noises still persist, you might really have a major water hammer problem so read on.
Drain your water system to replenish air chambers
Water hammer in pipes can be kept to a minimum by installing a new air chamber or a water hammer arrestor.
An air chamber is made of copper pipe that is used for absorbing water pressure by compressing it within the chamber. The chamber loses air as water come and go so it becomes less shock absorbent over time, causing that unwanted hammering noise.
So, to refill your air chambers with new air, follow these steps.
Locate the main valve of your water line and shut it off. Next, turn all faucets you could find around the house on. It’s also advisable to start with the highest water outlet in your house till you reach the lowest point.
Drain water from all open faucets and wait for 30 minutes. Make sure that water is also flushed from the toilet before turning the water supply on again to your house.
Observe for 10 minutes to see if the pressure is strong again to supply a steady stream of water throughout the pipeline. If successful, it should stop those banging noises.
Reduce water pressure
If the second tip doesn’t work at all, try to reduce water flow to your house by adjusting the water pressure regulator. This will lower water pressure and essentially help the pipes or air chambers absorb the shock wave to its capacity.
However, if you don’t have a regulator and a water pressure gauge, consider installing one so you can adjust water pressure whenever necessary at the right level. Make sure that your water pressure range doesn’t go beyond 30-55 psi to avoid further damage to your pipes.
Call a plumbing expert for assistance
If everything gets more technical than you expected, or if all else fails, contact a plumber near you immediately. Besides, other water hammer solutions like installing air chambers, arrestors, or even regulators can be a pain for a non-handyman.
Overall, whether you’re trying to resolve the issue on your own or hiring a plumber, regular maintenance is key to preventing water hammer from happening again.