Why does the water hammer only when I flush the toilet?

Author: Julian Reinger  |  Last update: Tuesday, September 26, 2023

Simple plumbing maintenance, such as tightening the washer screws, may help. If it doesn't, you'll need to replace the stem assembly. A faulty toilet fill valve that doesn't close completely or a quick-closing fill valve are both possible causes of water hammer that occurs after you flush a toilet.

Why does my toilet make a hammer sound after I flush?

If you hear a banging or a bumping noise coming from your pipes after you flush the toilet, you likely have a water hammer issue on your hands. This shockwave effect occurs after a sudden change in water pressure, causing the pressurized water to bang against the valve opening.

How do you stop pipes knocking after flushing toilet?

More often than not, you'll need a professional plumber to come in and install water hammer arrestors. These are small devices that are meant to protect against water hammer. Most modern homes use water hammer arrestors.

When I flush the toilet there is a clunking sound?

Does it sound like someone is standing behind your living room and bedroom walls knocking on them whenever a toilet flushes? If so, it's likely coming from your pipes. Also known as 'water hammer,' this knocking noise in your home's plumbing can become as annoying as a clogged toilet.

Is water hammer bad?

The Effects of Water Hammer

Leaks: Water hammer has the potential to damage joints, fittings and connections, resulting in poor seals and ultimately leaky pipes. Ruptured pipes: Ruptured pipes due to built-up pressure can be particularly expensive to repair.

Solving banging pipes when toilet flushes

Is water hammer a problem?

Water hammer is a key sign that damage may be occurring in your plumbing system. You must fix the cause of water hammer before it results in permanent damage.

Does water hammer need to be fixed?

If you begin hearing or feeling frequent water hammers in your home's pipes, it's important to act quickly to avoid potentially serious damage to your plumbing. One method for eliminating water hammers is to create new air chambers that will serve as cushions for shockwaves.

How do you permanently fix a water hammer?

This can be fixed by draining your plumbing system, which requires turning off the main water valve and opening the highest faucet in your home. Then drain water from the lowest faucet. The chamber should fill up with air once the water is drained and resolve your water hammer problem.

Can water hammer damage plumbing?

Water hammer can cause serious damage to pipelines, pipe joins gaskets, and all other components of the system like flow meters and pressure gauges. On contact, these pressure spikes can easily exceed five to ten times the working pressure of the system, placing a tremendous amount of stress on the system.

What can I use instead of water hammer?

Another easy way to eliminate water hammer is by installing a short vertical pipe close to the offending pipes. Commonly referred to as an “air chamber”, this fills pipe segments with air. This, in turn, creates a cushion for water when it suddenly changes direction.

What happens if water hammer is left untreated?

Left untreated, water hammer can lead to actual damage to pipework, appliances and components of any system. Over time this damage can accumulate and result in the premature failure of parts of the plumbing system and all the watery hassle that can cause.

Will turning water off stop water hammer?

You can cure water hammer by turning off the water behind the waterlogged chamber, opening the offending faucet and permitting the faucet to drain thoroughly. Once all the water drains from the chamber, air will fill it again and restore the cushion.

What are two causes of water hammer?

Water hammer is usually caused in high pressure (e.g. mains pressure) water systems either when a tap is turned off quickly, or by fast-acting solenoid valves, which suddenly stop the water moving through the pipes and sets up a shock wave through the water, causing the pipes to vibrate and 'shudder'.

Can I ignore water hammer?

Ignoring water hammer can ultimately result in the catastrophic failure of your flow system. The long-term effects of water hammer can include: Pump and Flow System Damage.

How long do water hammer arresters last?

A: Although arresters are typically tested to 10,000 cycles, Sioux Chief arresters have been independently lab tested to withstand 500,000 cycles without failure. All Sioux Chief arresters are guaranteed to control water hammer for the lifetime of the plumbing system.

When should I be worried about water hammer?

Enough force from water hammer can even cause pipes to burst. If you hear rattling sounds along with the water hammer, it likely means you have pipes coming loose.

Can air in pipes cause water hammer?

Water hammer most commonly occurs when these air chambers have too much water in them. While the chambers regulate pressure and prevent water from forming waves in your pipes, too much air can suddenly cause the opposite to occur.

Can a faulty toilet cause water hammer?

A faulty toilet fill valve that doesn't close completely or a quick-closing fill valve are both possible causes of water hammer that occurs after you flush a toilet.

How do you clear a water hammer?

How to stop water hammer
  1. Is air pockets the problem? Another issue that can cause a similar banging sound is actually air pockets in your pipes. ...
  2. Close valves half-way. ...
  3. Replace intake connections. ...
  4. Install water hammer arrestors. ...
  5. Secure the pipe. ...
  6. Install pressure limiting valve. ...
  7. Install different taps. ...
  8. Call the plumber.

Can a blocked pipe cause water hammer?

When modern plumbing is installed correctly and maintained, the pipes have air chambers inside that help soften the sudden stop of water flow and eliminate the sound of water hammer. A clogged air chamber can also cause water hammer, so it's important to make sure pipes are running clear.

Can shower cause water hammer?

Water Hammer

Water hammering is often caused by high water pressure in the pipes, which various factors, such as faulty pressure regulators or a malfunctioning water heater, can cause. It can also be caused by closing a valve too quickly, which can happen when a shower is turned off suddenly.

Do plumbers use hammer?

Ball peen hammer is used to strike on plumbing materials, to strike on chisel for dismantling the tiles, and to shape the metallic objects. It is also used for shaping and expanding the free end of the rivet. The head of a ball peen hammer is made to resist chipping.

Can a faucet cause water hammer?

While sink, tub, and shower faucets can cause water hammer, clothes washers and dishwashers can more often cause water hammer because they can shut off water faster than by hand. These appliances use solenoid valves, which can close off as quickly as 30 milliseconds.

Where do you put a whole house water hammer arrestor?

Exactly where to place the hammer arrestor will depend on the actual piping arrangement. The best places are either close to the pump, isolation or check valve that is originating the hammer, or at more distant points where the pipe changes direction, for example at the top of a pump riser.

Previous article
How easily does porcelain crack?
Next article
What does a stop pipe look like?