3 Common Causes of the Water Hammer Effect

A man works on a dishwasher.

The water hammer effect is commonly found in dishwashers, washing machines, or toilets. The effect is created when the flow of water is suddenly cut off causing a pressure build up to be released immediately. This is evidenced by a thud sound that can be heard when water stops. It is important to understand the common causes of the water hammer effect. Water hammers can damage pipes and result in a costly repair or replacement of a household appliance that you own.

The common causes of the water hammer effect on appliances and pipes in the home include shutting off water supply suddenly, an interruption in water service to the home, and closing a water valve quickly. These causes can be addressed in order to prevent your appliances from suffering the effects of the water hammer.

1. Shutting Off the Water Supply

When the water supply to your home is shut off suddenly and abruptly it causes the water hammer effect. This results in a sudden halt that will sound like the screeching of car brakes followed by a loud boom or bang. This is the pressure build up in the pipes that is being released and dispersed throughout the system. It is the same effect that happens if you were walking in a line of people and suddenly the first person stops abruptly, causing everyone behind to stack up against each other.

2. Interrupting Water Supply to the Home

Any interruption to your home's water supply that is sudden will also result in the water hammer effect being created. If there is any utility work that is taking place near your home or a flood or other damage that causes a city main water pipe to burst, the effect of this action will be the sudden stop of water and the release of pressure through the water hammer effect. Turning off appliances and shutting off valves when you are not in the home or using the water will prevent the effect of a water hammer on your dishwasher, washing machine, and other appliances that are attached to the home's water pipes.

3. Shutting Off a Valve Too Quickly

If you are working around the home when an appliance is using water such as the washing machine or dishwasher and you shut off the valve all of a sudden, this will produce a back up of pressure that will be released as a water hammer. This can easily be avoided by making sure that any work that you are doing that requires you to shut down the water is done when no appliances are running.

Some of the situations that create a water hammer in your home may be preventable while others may not be. For those situations that can prevent a water hammer, exercise caution and make sure that you do nothing that can contribute to the creation of this situation. For those situations beyond your control, call for information or ask your insurance company how you may be compensated from any resulting damage caused by the water hammer effect.