WHAT IS THE LOUD BANGING NOISE AFTER I FLUSH THE TOILET




Have you noticed that when you flush your toilets, there's a loud banging noise coming from walls?

This is called "water hammer." While this could cause major water damage, it's relatively simple to fix.

But first, let's explain why this is happening...

What is water hammer?

Water hammer is basically a multi-car pileup happening in your pipes.

Think of it this way: If a long line of cars was driving on the highway and the first car slams on its brakes, what would happen? Each car will likely run into the car in front of it.

That's what's happening in your pipes.

When your toilet flushes, it opens a valve to get more water and then suddenly shuts the valve off. The water that was rushing to your toilet is now cut off and the pressure causes your pipes to make a loud banging noise.

How serious is the banging noise?

Water hammer won't immediately cause any catastrophic problems. But the force could eventually break or loosen poorly soldered joints and fittings, which could cause a costly leak inside your home's walls.

So, fix it as soon as you can to avoid the possible consequences.

How to fix it

To help eliminate water hammer, small T-shaped air chambers are installed in your water line to act as shock absorbers.

However, over time, the water can displace the air in these chambers, leading to the banging noises you're hearing.

If your home has only recently begun making noise, this displacement is likely the problem.

Luckily, there's an easy solution: completely drain your plumbing system. Here's how:

  • Shut off your water supply at your water main.
  • Open all the faucets in your home and let them drain.
  • Flush all the toilets in your home.
  • Run the dishwasher and washing machine for a few minutes to drain them.
  • Once you're certain all the water has been drained, turn on your water again.

(Note: This may also be a good time to flush your water heater.)

Draining your plumbing system should get rid of the banging noises coming from your pipes when you flush your toilets. If it doesn't, there could be some other problems, including:

  • The air chambers are plugged
  • Air chambers weren't ever installed in your home
  • Your pipes have come loose from their support

However, you will likely need a professional plumber's help to fix these problems.

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