
What is water hammer? Generally water hammer is a loud banging noise coming from water pipes in your house when the flow of water is stopped abruptly. The noise can vary drastically depending on the specific circumstances. Common occurrences are when the washing machine stops filling, or when a sprinkler valve closes. Usually the higher the water pressure you have, the worse the symptoms (noise), will be. Also the more flow you have, the worse the symptoms are. The sprinkler system is usually the highest gpm flow device in your home. Most sprinkler systems are designed around 75% of your residences capacity. A hose faucet is usually the next highest flow device, but it usually has a slow closing manual valve to prevent sudden stops in water flow.
A common fix is to install a water hammer arrester.
A common fix is to install a water hammer arrester.
A water hammer arrester can be installed outside on the supply line going to the sprinkler system as well. Arresters come in different sizes to match the flow volume of specific devices. I use a 3/4 inch size for irrigation systems.
Water hammer can come from other sources as well. Proper diagnosis is critical. Some water hammer problems can occur when a sprinkler valve opens, versus closes. Trapped air in the piping can cause water hammer. A faulty pressure regulator can be the cause as well. In some rare instances, I have seen water hammer caused by a momentary reverse flow situation when water flow is started either by a hose faucet or irrigation valve opening. In this case a single check valve can remedy the problem when placed at the right location, usually after the supply valve to your house.
Securely fastening loose piping throughout you home can help keep the pipes from banging against the walls too.
Over time, many irrigation zone valves begin to close & open faster than originally designed. This is usually caused by the rubber diaphragms getting stretched out over time. Changing them, or the entire valve, can solve this efficiently. The same thing seems to happen in house pressure regulators (PRV). The diaphragms get weak causing the PRV to cycle or vibrate which can generate various whining sounds as well as causing pipes to bang.
Replacing the PRV will remedy the problem, or in cases where the supply line pressure is low (60psi), one can just remove the PRV.
Water hammer can come from other sources as well. Proper diagnosis is critical. Some water hammer problems can occur when a sprinkler valve opens, versus closes. Trapped air in the piping can cause water hammer. A faulty pressure regulator can be the cause as well. In some rare instances, I have seen water hammer caused by a momentary reverse flow situation when water flow is started either by a hose faucet or irrigation valve opening. In this case a single check valve can remedy the problem when placed at the right location, usually after the supply valve to your house.
Securely fastening loose piping throughout you home can help keep the pipes from banging against the walls too.
Over time, many irrigation zone valves begin to close & open faster than originally designed. This is usually caused by the rubber diaphragms getting stretched out over time. Changing them, or the entire valve, can solve this efficiently. The same thing seems to happen in house pressure regulators (PRV). The diaphragms get weak causing the PRV to cycle or vibrate which can generate various whining sounds as well as causing pipes to bang.
Replacing the PRV will remedy the problem, or in cases where the supply line pressure is low (60psi), one can just remove the PRV.